Wiring the Simulator - Aviation Wire

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aircraft wire by the roll

When I first began to work on my simulator, I used whatever wire was available; usually this was automotive electrical wire.  The wire was inexpensive and seemed to do the job; however, there were several shortcomings.  

To carry the appropriate amperage the wire selected was quite large in thickness; therefore, quite inflexible.  This inflexibility resulted in the wire coming loose at connections quite easily.  The thickness also made routing numerous wires quite challenging and at one stage, my simulator looked like a rat’s nest of snaking coloured wires.

After a few connection issues, I began to rethink my approach.  

I have since replaced the automotive wiring with a wire grade more suitable for the purpose.  The wire I use is aviation wire which is available in various gauges (thicknesses) and colour options.  The benefits in using this wire are it:

• Withstands physical abuse during and after installation 

• Has a good high and low temperature properties  

• Is very flexible and small enough to be run in tight places

• Can be obtained in varying gauges and colours

• Has a high flex life  

• Has good out-gassing characteristics

• Has a fair cold flow property (probably not that important as the simulator is not going to altitude)

The wire can easily be obtained in rolls from supply chain stores or from e-bay.  Enter the following wire reference code into either e-bay or google:  Part Number: 22759-16-22-9; 22 AWG WHITE TEFZEL WIRE.

Please note, this is the wire I use (and many other builders).  There is a wide variety of wire available in the market that is suitable for building, so don't become overly concerned if you've already used a different type of wire.  The main point to remember is that wire is rated to the application and voltages your intending to use.  The wire mentioned is ideal for all wiring requirements of the simulator with the exception of very high voltage requirements.  High voltage requires a wire of lower gauge (thicker wire) to ensure minimal voltage drop over distance. 

The same type of wire as mentioned above can be purchased in differing gauges (thicknesses).  I find 22 gauge is a good overall gauge to use.  Remember that voltage (amps) is rarely being applied to the wire continuously (exception is from power supplies).

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jr servo wire security clips

Easy Connect/Disconnect Connectors

Often there is a need to connect a piece of wire to another piece of wire or part and have the ability to be able to disconnect the wires easily and quickly.  For example, often panels must be removed from the center pedestal; having the ability to disconnect wires easily allows complete removal of the item without destroying the attachment wires!

There are dozens of connectors available for joining or extending wires – some are better than others.

I use (where possible and when voltage/amp requirements dictate) JR servo wire security clips.  These little clips allow three wires to enter to either side of the connection, are made from heavy duty plastic, and have a guaranteed clipping mechanism that will not unplug itself.  Search the Internet for JR extension servo clips. 

For applications requiring more than three wires, or higher voltage/amps, I use a high quality terminal block, Canon style plug or a D-Sub plug.  The later two requiring each wire to be very carefully soldered into the appropriate wire reciprocal in the plug.  I also use Mylar quick release plugs for some applications.

All other wires that require a permanent connection are usually soldered together with wire shrink wrap.  Soldering always provides the best connection.

Freight Dispatched - Throttle Quadrant Australia Bound

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A300-600 FedEx. Flaps2approach freight was dispatched on this aircraft (Maarten Visser from Capelle aan den IJssel, Nederland, N725FD A300-600 Fedex (4542200103), CC BY-SA 2.0)

It’s taken considerable time with frequent delays since I sold my earlier B737-300 series throttle quadrant, in October 2012, to make way for a replacement 600 series TQ with three-bay pedestal.

LEFT: FedEx. Copyright Bob Wood, Airplane Pictures.Net

As I expected, “scope creep” reared its head and the original requirements changed considerably over time.  It’s almost like leaving the house to buy a second hand car and coming back with a brand new jeep with all the accessories.

Use a Freight Forwarder

Freighting something as heavy and as large as a TQ, from the United States to Australia is not without cost and I’m fortunate to be in good stead with a competent Australian freight forwarder. 

A freight forwarder's job is to look after the logistics of getting the freight from point A to point B as expeditiously as possible.  Forwarders also complete all the required paperwork that is requested by customs authorities in both the country of export and import.  A good forwarder will do everything, albeit at a cost to you; however, the fee they charge is often worth the expense, as completing the required paperwork can be very difficult and if not correctly done will result in delays and storage charges.

Often a freight forwarder will sub contract his equivalent in the country of export to look after the exporting aspects of the freight.  A forwarder has access to any number of airlines and attempts to secure a freight rate that is acceptable to the client. 

Freight rates behave like shares on the stock market, and prices fluctuate widely depending upon the price of fuel, whether the freight can be back-logged (added to a pre-paid shipment belonging to someone else) or is dispatched stand alone.

How the Freight Industry Works

The way it works is quite simple – the freighter will charge you based on the cubic surface area or weight ($$$ / kilogram) of the crate.  The amount you pay is whichever is greater!  To this there are other charges added such as: airport fees, security fees, customs clearance fees, tax, import duties, airline handling fees, terminal fees, cargo automation fees, export clearance charges and a truck tail-lift pick-up fee.  This is above the actual cost per kilogram to send the freight and any domestic carriage, pick-up and storage charges.

You're probably thinking that sea freight is less expensive and you are correct; however, shipping terminal fees usually negate much of the saving, not too mention a lengthy wait time and a higher cost for insurance.

Carrier & Route Change - QANTAS then FEDEX

The freight industry is not a squeaky clean industry and under-the-carpet arrangements are commonplace.  If another carrier has space that is being sold at a cheaper rate, then your freight often will be shipped with the airline with the lesser expensive freight charge.  Unfortunately, this saving is not passed along to the customer, but equates to a higher profit for the freighter.  

The freight business have a term they use called "time sensitive", which basically translates to "we do what we want and you wait"!

For example, my freight was supposed to be freighted with QANTAS for a quick Los Angeles – Melbourne (KLAX-YMML) flight followed by a domestic service further south to Hobart (YMHB). 

However, space became available with FedEx at a cheaper rate than offered by QANTAS and the Ameriican freight forwarder made a carrier and route change.  Instead of LosAngleles to Melbourne, the crate was dispatched via a FedEx MD11 from KLAX to Honolulu (PHNL).  From here it will travel via a Fed EX 747-400 through to Sydney (YSSY) and then onto Melbourne.  From Melbourne a domestic carrier will continue the pilgrimage to Hobart…

For the consigner (me), the longer a trip takes and the more times the freight has to be unloaded, stored and reloaded into another aircraft the higher the probability of potential damage.  If your wondering what could go wrong, think about how heavy freight is moved about - they use a fork lift!

At least FedEx, like DHL and UPS are specialists in moving freight.

Large Crate - Taking Advantage of Volume

I've spent considerable time over the last 10 months or so tracking down and purchasing genuine B737 OEM parts required for the simulator.  These have been stored at my friend's house and have been packed inside the crate along with the TQ.  The crate is full to the brim of "goodies" that will keep me busy for months... 

It's good to know I've saved considerable future postage costs and reduced the global carbon footprint by being able to add things to this shipment.

Impatient Wait

It’s an impatient wait, knowing that as I write the crate of “goodies” has landed in Sydney and has been transferred to Melbourne.  The next hop is to Hobart, Tasmania.  It's a fact of life that transporting anything to Hobart (an island state) takes a inordinate amount of time, so delivery is not expected to mid next week.

It's said that waiting builds character; "I seem to wait all the time....."

Oh and if your curious, the cost to send 110 kilograms chargeable weight from the US to Australia is $1453.00 AUD total.  Whoever said that building a simulator was cheap, should be "shot on the spot"!

I'm looking forward to getting back into construction mode and posting new progress updates, explanations and photographs.

Update

on 2013-08-15 22:23 by FLAPS 2 APPROACH

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The crate has arrived....  It's much bigger than I anticipated.  This is the crate at the side entrance door to the house.. 

I had to make a winch and cradle system to enable me to get the crate, which weighs 110 kilos up and over the stairs and into the house.

At last, I now can get back into the construction phase of the simulator!

Time to find my wire, drill, clippers and multimeter.  There are so many OEM parts - which do I start on first.

Scope Creep - Keeping the Enemy at Bay

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The Swiss Army pocket knife.  How many tools does one want?  Where do you stop?  The knife does not have a fork or spoon (D-M Commons, Wenger EvoGrip S17, CC BY-SA 3.0)

Scope Creep is a term often used in management to define the continuous growth of a project both in expenditure and time.

This phenomenon can occur when the scope of a project is not properly defined, documented, or controlled. It is generally considered a negative occurrence, to be avoided.  This said, scope creep can add benefits to a project ultimately making the end product far better than otherwise anticipated.

Typically, the scope increase consists of either new products or new features of an already approved product design, without corresponding increases in resources, schedule, or budget. As a result, the individual risks drifting away from the original purpose and scope into unchartered territory. As the scope of a project grows, more tasks must be completed within the budget and schedule originally designed for a smaller set of tasks. Accordingly, scope creep can result in a project overrunning its original budget and schedule.

Guilty as Charged...

Am I guilty of scope creep - a resounding YES.  It can be difficult to maintain your original project scope, no matter how well defined at the onset of the project; new parts, better technology, better methods to accomplish tasks, and experience are all potential budget breakers...

Scope creep has a nasty habit of sneaking up on you unaware - a few dollars here and few dollars there, a yes to this and a yes to that, and before you know it, you are over committed and over budget.  Scope creep rarely is caused by the vendor, it is more the territory of the seller or manufacturer.  Most of us have bought a motor vehicle, and have driven the car home with the addition of a tow bar, roof rack, and high fidelity stereo system - all absolutely essential according to the car salesperson...

Although the simulator will be more feature rich, reliable and aesthetically pleasing, it's important to always keep a firm hand on what your original project lines were, and try not to stray too far from your goals.  There is always something greener on the horizon, and whilst it can be tempting to stray beyond the fence to savour the new grass, always ask yourself - is this going to improve the outcome of what I set out to do and is the extra expense worth the outcome. 

Time, or lack of

A second conundrum that simulator builders often face is time, or lack of. Everyone except the very young and the retired are impacted by time.

Remember, Rome was not built in a day and many simulators can take 3-4 years until reasonably complete. 

Whether we like it or not, the process of research, procuring parts, and construction takes an inordinate amount of time, and if left unchecked will also cost you an inordinate sum of money...

Just a few thoughts to think about.

Flight Deck Builders Toolbox - Multimeter

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fluke multimeter

Depending upon how much realism you’re seeking, the construction of a flight simulator can encompass a variety of techniques including: electrical, mechanical, metal and wood-working, computer and IT skills. 

The average person, unless gifted or working in these fields, rarely has the level of expertise needed to fulfill every facet of building.  Fortunately, there are others that have travelled along the same path and assistance is often relatively easy to find from the Internet and dedicated builder forums.

One skill I was lacking was electrical.  As a youngster I had dabbled with car radios, stereos and installed numerous two way radios into cars and boats.  I can remember sparks flying here and there as I connected wires incorrectly.  The only gadget I owned then was a retro-looking screwdriver that had a handle that illuminated whenever a live wire was touched.

Although many builders opt for pre made parts that do not require wiring and soldering, there will come a time when you have to do this yourself, especially if you are using real aviation parts converted to flight simulator.

The Multimeter

A multimeter is used for diagnosing problems with electrical systems and is probably the most useful tool any builder can have in his arsenal of tools.   If I’d had access to a multimeter in my earlier years, I’m sure the sparks would not have been as bright as they were and I wouldn’t have' fried' as many fuses and radio components as I did.

Most multimeters can be used to measure a number of variables, the most valuable in my opinion being the ability to measure of continuity.

Continuity Testing - numerous examples

One of the basic uses a multimeter has in flight deck building is to test for continuity.  Testing for continuity checks to see if there is an electrical connection between two points. If two points are electrically connected, they are said to be continuous and the current will flow unheeded.  

Testing for continuity has many useful purposes.

For example, you can determine which prong on a multi-prong Canon plug is being used to carry 5 Volts to power the back lighting on a real aviation gauge or panel.  Another example is checking to ensure current flow across wires from an interface card to a sim part.  

A further example is aircraft bulbs.  Often they are so small that viewing the filament to determine connectivity is next to impossible.  Grab your meter and place a probe on the outside of the bulb (the earth) and place the other probe at the power end of the bulb (positive).  If you hear the meter beep then the filament is not damaged and current can flow, however, if you don’t hear the beep, then the current is not flowing and the filament is damaged requiring a replacement bulb.  A similar test can be done with fuses.

Continuity testing can also help you test your soldered connections to see if they were soldered correctly.  A beginner who is not experienced in visually detecting problems with a soldered joint can become frustrated very easily, because a soldered joint can look like its soldered correctly but there may not be an electrical connection. Using a mulitmeter helps you find out if the soldered connection is good or not.  Similarly, the tool can also be used to determine if a correctly connected wire is broken somewhere along the wire’s strand.

How to Test for Continuity

Set your multimeter to the correct mode.  Look for the icon that looks like a sound wave or a Wi-Fi connection indicator on the meter.  If you can't find it refer to the manual you received with the multimeter.

• Using the pencil probe (red or black wire), touch the connection you want to test.  

• Using the other probe, touch the other end of the connection you want to test.

• If you hear a beep or a buzz, there is an electric connection between the two points. 

• If there is no electrical connection you will not hear a beep or a buzz and the display will give a reading of 0.

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Note the black probe is touching the outer casing (earth) whilst the red probe is being moved from prong to prong.  An audible beep from the multimeter will sound when the prong touches the power prong.  It's important to ensure you are only touching one prong at a time, otherwise you will get an incorrect result

Example - Connecting Back Lighting

Using continuity, let’s look at the example mentioned earlier: connecting power to illuminate back lighting on an OEM gauge that uses a multi-prong canon plug.   

We need to determine which of the prongs from the plug carries power (positive) and which is earth.  

To check for power, touch one of the two probes to one of the prongs in the Canon plug.  Then, attach the other probe to the lower positive end of the bulb (not the bulb casing).  Move the first probe from prong to prong in the Canon plug until you here a beep.  The beep indicates that this prong is the power prong. 

1. To determine earth, do the same technique, but instead of using the bulb, touch the probe against the outer casing of the Canon plug.  With the other probe move it between each of the prongs in the plug.  When you hear the beep this will indicate which prong is earth.   

2. The wires from the power supply (positive and earth) are then connected to the indicated prongs.  If connected correctly, the backlighting for the panel will illuminate.

The same can be done for switches and toggles or for almost any part.  Let's look at another example: 

Example - Connecting a Switch or Toggle

In this case we have a three-was switch often used in the overhead.  The switch can be moved to three positions and can be locked in one position.  The rear of the switch has three terminals.  before going further, it's important to realize that although a switch may have up to eight terminals, not every terminal is needed to connect to the simulator.  The reason there are often ancillary terminals is that in the real aircraft, a switch may also connect to other devices that a simulator does not need (such a centralized computer).

To determine which switch position correlates to the actual turning on or off of the function we need to:

1. Place the black probe on the earth or common terminal.

2. Place the red probe on another terminal (alligator clips are handy you secure the probe to the terminal).

3. Move the switch toggle up and down until you hear the multimeter beep.  The beep signifies that power can travel through the circuit.

4. Remember the position of the switch and the terminal used.

5. Repeat the process with all terminals and double check results to ensure accuracy.

6. Once the terminals (or pin-outs are known) connect the nominated wires from the interface card and programme whatever functionality is required in the  flight avionics software.

Other Functions and Uses

Testing for continuity is but one operation of a mulitmeter, and depending upon the type and quality of the tool, there will be other functions available, such as being able to measure current, resistance and voltage.  The last function is very handy to flight deck builders as often we use multiple voltages ranging from 3, 5, 12 and 28 Volts.  By turning the dial to the appropriate voltage selection, one probe is used to touch one side of the wire and the other probe the device.  This will determine what voltage current is travelling through the wire to/from an interface card.

Measuring current (amperage) is equally important, and to determine current flow between points, the probes are connected to each side of the device to be measured (after the red probe is placed into the AMP socket of the multimeter).  With the probes effectively interrupting the current flow, the meter is 'in-line' and any current travelling between the components will be able to be measured and displayed by the meter in amps.  

To measure the amerage, a multimeter must have an AMP function. 

There you have it, the very basics of a multimeter and why it’s important to have one in your toolbox.

Thankfully, I’ve not had any sparks or melted wires building the simulator and it’s primarily because I always use a multimeter to check any work I’ve done before turning the power on.  

I still have a retro flashing screwdriver, but it’s more a keepsake than an operational tool.

To read a sister post, navigate to: Using Interface Cards and Canon Plugs to Convert OEM 737 Parts.

Below; Multimeter explanation and demonstration (courtesy of Afro-tech-mods (U-Tube creative commons license).

Take Off / Go Around (TOGA) - Explained

Performing Go-Around can be a confusing procedure, made more so by the effects of inclement weather. 

TO/GA is an acronym for Take Off / Go Around.  TO/GA is used whenever an approach becomes unstable or environmental conditions alter that do not allow an approach and landing within the constraints that the aircraft is certified.  If you watch the short video (embedded from U-Tube) you will note that the crew utilized TO/GA when a rain squall reduced visibility to almost zero as the aircraft was about to cross the runway threshold.

VIDEO: Boeing Business Jet (BBJ)  - Final Approach engaged TO/GA due to inclement weather (courtesy & copyright "DougLesso" U-Tube).

So why is TO/GA confusing?  It’s not the actual use of TO/GA that is confusing, but more the level of automation you have in use at the time of engaging TO/GA.  By automation, I am referring to  the command mode selected for the approach: VNAV, LNAV, V/S, ILS and whether the autopilot is enaged or not (CMD A/B).  In this post three three distinct scenarios will be discussed; however, engine out (single engine) procedures will not be examined.

Scenario One

Autopilot Flight Director System (AFDS) configured for autoland:  CMD A & B engaged with localizer and glideslope captured and 'FLARE armed' and annunciated on the Flight Mode annunciator (FMA).  Auto throttle engaged.

• Pushing the TOGA buttons will engage the Take Off / Go Around mode & Flight Director guidance will 'come alive';

• The auto throttle will automatically move forward to produce reduced go around (RGA) thrust;

• The Thrust Mode Display (TMD) will annunciate TO/GA and the required thrust will be displayed;

• The autopilot will remain engaged and will pitch upwards to follow the Flight Director (FD) guidance

• Landing gear will need to be raised and flaps retracted on schedule; and,

• A 'bug up' will be observed on the speed tape of the Primary Flight Director (PFD) which indicates flap retraction speeds.

Scenario Two

Autopilot Flight Director System (AFDS) configured for manual landing (autopilot on):  CMD A or B engaged.  Auto throttle engaged.

• Pushing TO/GA buttons will engage the Take Off / Go Around mode & Flight Director Guidance will 'come alive';

• The auto throttle will automatically move forward to produce reduced go-around thrust.  However, the autopilot will disconnect;

• The Thrust Mode Display (TMD) will annunciate TO/GA and the required thrust will be displayed;

• The crew will need to take control and manually fly to follow the Flight Director guidance (around 15 Degrees nose up);

•  Landing gear will need to be raised and flaps retracted on schedule; and,

•  A 'bug up' will be observed on the speed tape of the Primary Flight Director (PFD) which indicates flap retraction speeds.

Scenario Three

Autopilot Flight Director System (AFDS) configured for manual landing (autopilot off):  CMD A or B not engaged.  Auto throttle engaged/not engaged.

• Pushing TO/GA buttons will engage the Take Off / Go Around mode and Flight Director guidance will 'come alive';

• The crew will need to take control and manually fly to follow the Flight Director guidance (around 15 Degrees nose up);

• The auto throttle will not command reduced go around thrust.  The crew must manually move the throttle levers to roughly 85% N1;

• Landing gear will need to be raised and flaps retracted on schedule; and,

• A 'bug up' will be observed on the speed tape of the Primary Flight Director (PFD) which indicates flap retraction speeds.

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The black TOGA buttons are prominent on each of the thrust levers. OEM 737-800 throttle quadrant

How is TO/GA Engaged

The Boeing 737 has two buttons on the throttle quadrant for engaging TO/GA.  These buttons are located on each thrust handle below the knob of the thrust levers.  The TO/GA buttons are not the buttons located at the end of each throttle knob; these buttons are the auto throttles (A/T) disconnect buttons.

Pushing one or two of the TO/GA buttons will engage the go-around mode and command Flight Director guidance for attitude pitch.

Depending on the level of automation set, but assuming minimal automation, the pilot-flying may need to push the throttle levers forward to roughly 85% N1 (Reduced Go Around Thrust).  Boeing pilots often refer to this technique as the 'Boeing arm' as an outstretched arm grasping the throttle levers moves the levers to 'around' 85% N1.

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fma displays for toga

If the crew pushes the TO/GA button once, reduced go-around power is annunciated on the Thrust Mode Display (above the N1 indications on the EICAS screen) and also in the Flight Mode Annunciator (FMA).  Reduced go-around thrust is roughly 10% below the green coloured reference curser on the N1 indicator.  This thrust setting will generate a rate of climb between 1000 and 2000 fpm.

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Flight Mode Annunciator (FMA) on Primary Flight Display (PFD) indicated TOGA and TOGA will be displayed on Thrust Mode Display (TMD).  Replace CRZ (1) with TO/GA

If the TO/GA buttons are pressed again (two button pushes), go-around thrust will be set to maximum thrust (at the reference curser). Engaging the TO/GA button twice is normally only used if terrain separation is doubtful.

A Typical Go Around (CAT 1 Conditions)

The pilot flying focuses on the instruments as the aircraft descends to about 200 feet AGL.  The pilot not flying splits his attention between his responsibilities to both monitor the progress of the approach, and identify visual cues like the approach lighting system.   If the approach lights of the runway come into view by 200 feet, the monitoring pilot will announce 'continue' and the flying pilot will stay on instruments and descend to 100 feet above the runway.

If the non-flying pilot does not identify the runway lights or runway threshold by 200 feet AGL, then he will command 'Go Around Flaps 15'.  The pilot flying will then initiate the Go Around procedure.

The pilot flying will engage the TOGA command by depressing the TO/GA buttons once, resulting in the Flight Director commanding the necessary pitch attitude to follow (failing this the pitch is roughly 15 Degrees nose up).  The auto throttle (depending on level of automation selected) will be commanded to increase thrust to the engines to attain and manage a 1,000 foot per minute climb; a second press of the TOGA buttons will initiate full thrust.  

The pilot not-flying will, when positive rate is assured, raise the landing gear announcing 'gear up all green' and begin to retract the flaps following the 'bug' up schedule as indicated on the Primary Flight Display (PFD).  Once the Go Around is complete, the Go Around Checklist will be completed.   

Important Points to Remember when using TOGA

• If the Flight Directors (FD) are turned off; activating TO/GA will cause them to 'come alive' and provide go around guidance.  

• Engaging TOGA provides guidance for the flight modes and/or N1 setting commanded by the auto throttle, It will not take control of the aircraft.  If the autopilot and auto throttle is engaged then they will follow that guidance; however, if the autopilot is not engaged the crew will need to fly the aircraft.

• TOGA will not engage the auto throttle unless the autopilot is engaged.  The only way to engage auto throttle is with your hand (flip the switch on the MCP).  See sidenote below.

• TOGA will engage only if the aircraft is below 2000 RA (radio altitude).

• TOGA will engage only if flaps are extended.

• Remember to dial the missed approach altitude into the Mode Control Panel (MCP) after reaching the Final Approach Fix (FAF). The FAF is designated on the approach plate by the Maltese cross.  This ensures that, should TOGA be required, the missed approach altitude will be set.

Side-note:  It is possible to engage the auto throttle using the TO/GA buttons if the auto throttle is in ARMED mode and the speed deselected on the MCP.  Note this method of auto throttle use is not recommended by Boeing.

Flight Crew Psychology

Flight crews are as human as the passengers they are carrying, but it’s difficult to accept that a Go Around is not a failure, but a procedure established to ensure added in-flight safety.  Several years ago airline management touted that a go-around required a detailed explanation to management; after all, a go-around consumes extra fuel and causes an obvious delay as the aircraft circles for a second landing attempt. This philosophy resulted in several fateful air crashes as flight crews were under time and management pressure to not attempt a go-around but continue with a landing.

Management today see the wisdom in the go-around and many airlines have a no fault go-around policy.  This policy is designed to remove any pressure to land in unsafe conditions - regardless of the reason: visibility, runway condition, crosswind limits, etc.  If one of the pilots elects to go-around, that decision will never be questioned by management.  So while TO/GA isn't the desired landing outcome, a go-around is not considered a failure in airmanship.

Minimal Discussion

This post has briefly touched on the use of TO/GA in an approach and landing scenario; nonetheless, to ensure a more thorough understanding, I urge you to read the Flight Crew Operations Manual (FCOM) available for download in the Training and Documents section of this website. 

Acronyms Used

• AFDS - Autopilot Flight Director System

• A/T - Auto Throttle Category 1 - Decision height of 200 feet AGL and a visibility of 1/2 SM

• CMD - Command A or B (autopilot)

• FAF – Final Approach Fix

• FD - Flight Directors

• FMA - Flight Mode Annunciator

• FPM - Feet Per Minute

• MCP - Mode Control Panel

• N1 - Commanded Thrust % (rotational speed of low pressure spool)

• RA - Radio Altimeter

• RGA – Reduced Go-Around Thrust

• TMD - Thrust Mode Display (on EICAS display)

• TO/GA - Take Off / Go Around. Written either as TO/GA or TOGA

Avoiding Confusion: Acceleration Height, Thrust Reduction Height, Derates, Noise Abatement and the Boeing Quiet Climb System

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Thompson B738NG transitioning to Acceleration Height, Manchester, UK (Craig Sunter from Manchester, UK, Boeing 737-800 (Thomson Airways) (5895152176), CC BY 2.0)

During preparation for takeoff, three similar functions that deal with how the autothrottle calculates N1 thrust can be altered in the CDU: Acceleration Height (AH), Thrust Reduction Height (TRH) and the Quiet Climb System (QCS).  Although there are similarities, each function is used independently of each other. 

Confusion can also occur deciphering the different methods used to alter N1 thrust, such as: Derated Thrust, Assumed Temperature and Derated Thrust Climb.

Acceleration Height (AH)

Acceleration Height is the altitude above ground level (AGL) that a pilot accelerates the aircraft by reducing the aircraft’s pitch, to allow acceleration to a speed safe enough to raise flaps and slats, and then reach the desired climb speed.

Part 23 of Federal Aviation Regulations (USA) dictates that the airplane is able to climb at a certain rate in this configuration up to a safe altitude.

The acceleration height is the altitude that the aircraft transitions from takeoff speed (V2+15/20) to climb out speed.  This altitude is usually between 1000 and 1500 feet, but may be as low as 800 feet; however, can differ due to noise abatement, airline policy, or airport specifics such as obstacles, etc.

The reason for acceleration height is to allow a safety envelope below this altitude should an engine problem develop after rotation; engines are set to maximum thrust, and the plane is pitched for V2 safety speed (V2+15/20).

Acceleration Height is altered in the CDU 'Init/Ref Index/Takeoff Ref Page (lsk4R) Accel HT ---- AGL'

Practical Application

Once the Acceleration Height has been reached, the pilot flying will reduce attitude pitch by pushing the yoke forward to increase speed.  As the speed increases Flaps 5 is retracted.  At this time the speed will need to be increased in the MCP speed window from V2 to climb speed, followed by further flap retraction on schedule. 

Although crews use slightly varying techniques; I find the following holds true for a non-automation climb to 10,000 feet AGL.

• Set the MCP to V2

• Fly the Flight Director cues to Acceleration Height (which will be at V2+15/+20).

• At Acceleration Height, push yoke forward reducing pitch.

• As forward speed increases you will quickly pass through the schedule for initial flap retraction – retract flaps 5.

• Dial into the MCP speed window the appropriate 'clean up' speed (reference the top bug on the speed tape of the PFD, usually 210-220 kias).

• Continue to retract flaps as per schedule.

• After flaps are retracted, engage automation (if wanted) and increase speed to 250 kias or as indicated by Air Traffic Control.

NOTE:  If the acceleration height has been entered into the CDU, the Flight Director bars will command the decrease in pitch when the inputted altitude has been reached - all you do is follow the FD bars.

Thrust Reduction Height (TRH)

The main wear on engines, especially turbine engines, is heat. If you reduce heat, the engine will have greater longevity. This is why takeoff power is often time limited and a height established that thrust is reduced. The difference between takeoff thrust and climb thrust may only be a few percent, but the lowering of EGT reduces heat and extends engine life significantly. 

The thrust reduction height is where the transition from takeoff to climb thrust takes place.  TRH can be altered in the CDU 'Init/Ref Index/Takeoff Ref Page 2/2 (lsk1R) Reduction AGL-- AGL'

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Figure 1: Thrust Mode Display (TMD).  In this example it is displaying CRZ (cruise). Figure copyright FCOM

The height used for thrust reduction, not taking into account noise abatement, can vary and be dependent on airline policy. Typically it falls between 800-1500 feet AGL. 

Once takeoff has occurred, examination of the Thrust Mode Display (TMD) will alert the flight crew to the type of climb that has been chosen.  The TMD will display the acronym TO (takeoff) or R-TO (reduced takeoff thrust) and will alter to CLB (climb) once the Thrust Reduction Height has been reached.

Confusion between Acceleration Height and Thrust Reduction Height

Newcomers are often confused between the two similarly-sounding terms, possibly because they both occur at the interface between takeoff and climb-out.  Simply written:

Acceleration Height is when the nose is to be lowered to allow the aircraft to accelerate. When the aircraft starts accelerating is when the flight crew will retract flaps as per the schedule.  Thrust Reduction Height is when the autothrottle will decrease the engine power to the pre-selected climb thrust; thereby reducing engine wear and tear.  Both may occur simultaneously or at differing heights above ground level.  Both can be configured in the CDU.

Differing Methods to Alter Thrust:  Derated Thrust (CLB-1, CLB-2), Assumed Temperature & Derated Thrust

There are several methods available to flight crews to alter N1 thrust controlled by the autothrottle system, and with the exception of the N1 speed reference knobs on the Main Instrument Panel (MIP), all are accessed via the CDU interface.

Derated Thrust (Derates):  Derate is a term used for derated thrust (or reduced thrust). 

The CDU displays a list of fixed-rate derates which may differ between aircraft, the reason being that each airframe may have a different powered engine.

Derates can be accessed from the N1 Limit Page.

Assumed Temperature:  This method calculates thrust based on a higher than actual air temperature and requires the crew to input into the CDU a higher than normal outside temperature.  This will cause the on-board computer to believe that the temperature is warmer than what it actually is; thereby, reducing N1 thrust.

The outside air temperature can be altered in the N1 Limit Page (lsk1L) or from the Takeoff Ref Page 2/2 (lsk4L).

Derated Thrust Climb (CLB-1 & CLB-2):  Selecting CLB-1 or CLB-2 commands the autothrottle to reduce N1 thrust during any climb phase to a higher altitude.  

Rather than use maximum climb or rate, crews often select CLB-1 which is approximately a 10% derate of climb thrust (climb limit reduced by 3% N1), while  CLB-2 is approximately a 20% derate of climb thrust (climb limit reduced by 6% N1).   Flight crews routinely pre-select a lower than maximum climb thrust before departure.

CLB-1 and CLB-2 can be accessed from the N1 Limit Page. 

The reduced climb thrust setting, no matter which method used, gradually increases to full rated climb thrust by 15,000 feet.

Quiet Climb System (QCS) - Abiding with Noise Abatement Protocols

Boeing has developed the Quiet Climb System, an automated avionics feature for quiet procedures that causes thrust cutback after takeoff.  By reducing and restoring thrust automatically, the system lessens crew workload and results in a consistently less noisy engine footprint, which helps airlines comply with noise abatement restrictions. There are two variables to enter: Altitude reduction and altitude restoration.

During the take-off checklist procedure, the pilot selects the QCS and enters the altitude at which thrust should be reduced.  The thrust reduction altitude is greater or equal to 800 ft AGL and the thrust restored altitude is typically 3000 feet AGL, however the altitudes may alter depending on obstacle clearance and the noise abatement required. 

With the autothrottle system engaged, the QCS reduces engine thrust when the cutback altitude is reached to maintain the optimal climb angle and airspeed. When the airplane reaches the chosen thrust restoration altitude (typically 3,000 ft AGL or as indicated by noise abatement procedures), the QCS restores full climb thrust automatically.  Note that the minimum altitude that the QCS can be set is 800 feet AGL.  This allows the safety envelope dictated by Acceleration Height to remain active.

Multiple Safety Features for Disconnect

The Quiet Climb System incorporates multiple safety features and will continue to operate even with system failures. If a system failure does occur, there are several methods for exiting QCS.  In the most common method, the pilot selects the takeoff/go-around (TOGA) switches on the throttle control levers. The pilot can also take control of the throttles easily by disconnecting the auto throttle and controlling the thrust manually.

The Quiet Climb System, also known as 'cutback' can be accessed from the Takeoff Ref Page (lsk6R).  You will observe the name cutback with on/off.  You can also enter an altitude that you wish the system to restore full thrust.

For completeness, below is a copy of the current Noise Abatement Departure Procedures (NADP). Click image for larger view.

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Noise Abatement Departure Procedures (NADP)

Similarity of Terms

When you look at each of the above-mentioned three functions they appear similar in many respects. 

The way I remember them is as follows:

Acceleration Height (AH) is the altitude above ground level (AGL) that is set to ensure take-off speed (V2+15/20) is maintained for safety reasons. 

Thrust Reduction Height (TRH) is the altitude above ground level (AGL) that is set to reduce take-off thrust a few percent to maintain and increase engine life.

The Quiet Climb System (QCS) allows a minimum and maximum altitude to be set in the FMC; thereby, reducing engine power and engine noise.  The restoration altitude is the altitude that full climb power is restored.  The QCS is used only for noise abatement. 

Thrust Reduction Caveat

It must be remembered that any thrust reduction made within the CDU is accumulative.  For example, if you select a lower fixed-rate derate and then select a reduced N1 by the assumed temperature method, the thrust reductions will be added.  It is imperative that the crew actually look at the N1 power settings to ensure they are suitable for the weight of the aircraft, environmental conditions, and length of the runway.  To check and confirm the N1 settings, look at the Thrust Mode Display or the appropiate page in the CDU.

ProSim737

The ProSim737 avionics suite includes the Boeing Quiet Climb System, Thrust Reduction Height, and Acceleration Height. The variables relative to each can be changed in the CDU.

Quality Assurance (QA)

This has been a long post dealing with items that are often confusing in their own right.   Rather than separate the similar topics into individual posts, I thought it easier to deal with them together.

When explaining procedures, I  attempt to keep the writing style simple and easy to understand for a wide range of audiences.  If I have failed, or you discover a mistake, please contact me so this can be rectified.

Acronyms Used

• AH – Acceleration Height

• AGL – Above Ground Level

• CDU – Control Display Unit

• CLB-1 & CLB-2 – Climb 1/2

• DERATE – De-rated Thrust

• FMC – Flight Management Computer

• LSK1R – Line Select 1 Right (CDU)

• PFD - Primary Flight Display

• QCS – Quiet Climb System

• R-TO – Reduced Takeoff (thrust)

• RTC – Reduced Takeoff Climb

• TRH – Thrust Reduction Height

• TO – Takeoff (thrust)

• TMD – Thrust Mode Display

Simulator Construction Update - June 2013

Building has been rather slow the last couple of months, although design wise quite a bit has been accomplished.  My main hurdle has been waiting for the replacement throttle quadrant and pedestal to arrive from the United States. 

The throttle has taken considerable time to correctly interface to allow full automation, and the initial brief has been changed to enable the interface cards that the throttle uses to be housed in a dedicated interface module.  The interface module is a trial to determine the feasibility of a modular design.

it's unfortunate, that building cannot continue in earnest until the throttle, pedestal and master module is installed.

I’ve been reliably informed that the new unit is expected to arrive sometime in late August.  There are some surprises in store which I’m sure you will find interesting.

In the meantime, I’ve been busy searching for and purchasing second-hand Boeing parts for some panel additions to the center pedestal and acquiring OEM 737 toggles, switches and bits and pieces for the forward and aft overhead panels.

Construction posts will continue shortly, however, until then I’ll continue to publish posts pertaining to operational procedures for the 737-800.

As with all my posts, if you find a glaringly obvious mistake, please tell me so I can rectify the discrepancy.

Searching for Definitive Answers - Flight Training

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First Officer conducts pre-flight check list & compares notes.  Whilst check lists are essential in ensuring that all crews operate similarly, there is considerable variance in how flight crews actually fly the 737

Learning to fly the 737 is not a matter of 1, 2, 3 and away you fly; there’s a lot of technical information that requires mastering for successful and correct flight technique.  Searching for a definitive answer to a flight-related question can become frustrating.  Whilst respondents are helpful and want to impart their knowledge, I’ve learnt through experience that often there isn’t a definitive answer to how or why something is done a certain way.  

Typical Pilot-type Personalities

Typical pilot personalities nearly always gravitate towards one answer and one correct method; black or white, right or wrong – virtual pilots or “simmers” behave in a similar fashion.  They want to know with certainty that what they are doing replicates the correct method used in the real-world. 

In reality, the Boeing 737 is flown by different crews in different ways all over the globe every minute of the day.   Often the methods used are not at the discretion of the crew flying, but are decided by airline company policy and procedures, although the ultimate decision rests with the Captain of the aircraft.  

For example, climb out procedures vary between different airlines and flight crews.  Some crews verify a valid roll mode at 500’ (LNAV, HDG SEL, etc) then at 1000’ AGL lower pitch attitude to begin accelerating and flap retraction followed by automation.  Others fly to 1500' or 3000’ AGL, then lower pitch and begin to "clean up" the aircraft; others fly manually to 10,000’ AGL before engaging CMD A. 

Another example is flying an approach.  Qantas request crews to disengage automation at 2500’ AGL and many Qantas crews fly the approach without automation from transition altitude (10,000’ AGL).  This is in contrast to many European and Asian carriers which request crews to use full automation whenever possible.  In contrast, American carriers appear to have more latitude in choosing whether to use automation.

Considerable Variance Allowed

The below quote is from a Qantas pilot.

• There is considerable tolerance to how something is done, to how the aircraft is flown, and what level of automation , if any, is used. Certainly whatever method is chosen, it must be safe and fall within the regulatory framework. There are are certainly wrong ways to do things; but, there is often no single right way to do something.

Therefore; when your hunting for a definite answer to a question, remember there are often several ways to do the same thing, and often the method chosen is not at the crew’s discretion but that of the airline.

Genuine B737 Forward & Aft Overhead Panels Purchased

For some time I’ve been debating whether to use a reproduction or OEM forward and aft overhead panel.  I have been favouring an OEM panel as this is in line with using genuine parts in the simulator, however, the overhead is a complicated piece of kit and ensuring complete functionality would be a challenge.

RIGHT:  Forward Overhead Panel.  The centre panels will be replaced to conform to a 737 Next Generation.  Panel was removed from a United Airlines 737-300 aircraft.

Certainly, using an overhead panel made by Flight Deck Solutions (FDS) is an easier option, however, despite their reproduction panels being high quality, there are discernible differences between reproduction and OEM panels.  

OEM 737 Overhead Panel Purchased

My decision was made for me when I was told a forward and aft overhead had become available from a recent 737 pull down.  Rather than remain indecisive, I thought I’d jump in “boots and all” and purchase it.  The two overhead panels have come from B737-300 and include the frames, DZUS rails, center panels, Cole engine starter switches, landing gear toggles and various other knobs and toggles.

I’m impressed at the condition of the panels; usually when panels are removed from an aircraft in a tear down yard there is little care given, and the frames become scratched, dented, or damaged in some way.  The frames I have purchased appear to be in relatively good condition.  

Cole Switches

I was fortunate that the two engine starter switches (Cole switches) were included.  These switches are made to exacting requirements and use a solenoid mechanism. 

LEFT:  Difficult to find operating Cole switches are used on all Boeing airframes from the 727 through to the Next Generation.

Purchasing Cole switches individually is quite expensive, so I'm pleased they were not striped from the overhead.

Panels and Backlighting

When I began to construct the simulator in mid 2011, I was adamant that backlighting should match that of the MIP, throttle quadrant and center pedestal.  I believe it was around 2006 that Boeing began to replace bulbs in favour of LEDS.  Certainly, the latest made Boeing uses LEDS. Therefore, my opinion has changed and I am happy to mix bulbs and LEDS (within reason)

The use of bulbs in the overhead uses a lot of power and generates considerable heat; using LEDS minimises power consumption and produces less heat.  If the LEDS are installed correctly, their resultant light is very similar to that of bulbs, and the brightness observed in the real aircraft.

Ultimately the back lighting will be dependent on whether I decide to use older style genuine Boeing panels or reproduction panels.

Realism & Authenticity - How Far Do You Go

Some flight deck builders go to extremes to ensure their flight decks replicate exactly what is seen in the real aircraf,t and while this is admirable, this is not the route I am 'religiously' going to travel.  There has to be compromise between replicating something exactly and having a functional flight simulator.

The end product will  be a combination of genuine (OEM) and reproduction parts - mostly OEM.

Furthermore, serious thought must also be given to how the overhead is going to be installed to the simulator; whether it be to a shell, such as produced by FDS or to a custom-made roll cage assembly.

I'll keep the Blog updated as parts are found and the overhead is developed.

• Unfortunately I do not have any high quality pictures. These images were supplied by the vendor. Currently the overhead is still located in the US.  In time better quality images will be uploaded.

B737-800 Cabin Phone System Panel - Center Pedestal

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oem 737-800 cabin phone panel: Panel has three push buttons with backlighting and legends, and one toggle button

I recently acquired an avionics panel that is a little different to the norm.  The panel was acquired from a company that was responsible for altering the on-board communication system for 50 Boeing 737-800 jetliners; the aircraft were being refitted with global communication equipment.  The upside for me was that the panels were being decommissioned and were not required by the supplier.

Late model 737 Next Generation panels are uncommon to find; therefore, it is interesting to observe the differences between the older style classic panels regularly seen on e-bay, and a newer style panel. 

The first thing that comes to mind, other than condition, is the lack of a rear box assembly on this panel.  Instead of an aluminum box, the wiring is protected by a stainless bracket assembly.  The wiring harness is also more refined and neater looking, while the backlighting, rather than using 5 Volt bulbs uses LED technology.

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oem 737-800 cabin phone panel. note the crispness of the legend

LED Technology

Most people are familiar with the 5 volt incandescent bulbs used to illuminate the light panels in Boeing aircraft - the bulbs produce a soft yellow-orange hue.  The colour temperature is in stark contrast to the white hue produced by LED technology. 

I believe that airframes post 2006 utilise LED technology.  Notwithstanding this, until older airframes are phased out, panel lighting will be a mixture of incandescent and LED lighting, or a combination thereof. 

Matching Colour Hue

Attempting to match the backlighting colour hue, especially in the center pedestal and overhead panels has always been a challenge for flight deck builders, especially when using an assortment of older style OEM panels and panels made by differing companies (FDS, CP Flight, Open Cockpits, SimWorld, etc).  

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Wiring is very neat and the panel does not utilise the more commonly found aluminum box structure

What many virtual pilots forget, is that the only purpose for an airlines’ existence is to generate income and a profit for the company. Pilots on the other hand are more concerned with flying the aircraft. 

There is very little thought as to whether a panel's backlighting is the same colour hue throughout all the panels.  If and when a panel needs to be replaced, a technician’s only concern is getting a workable and certified instrument fitted into the aircraft as quickly as possible. 

it is not unrealistic to have a few LED panels scattered amongst older bulb illuminated panels

Cabin Phone System Panel - What Works

Although there is no obvious use for this panel in the simulator, it is a good-looking panel that improves the overall aesthetics - it fills a 'gap' in the three-bay center pedestal.  The buttons do function and when depressed change colour and provide different cautionss.  Lifting the red cover and pushing the toggle to test causes the third button to illuminate 'smoke' in orange.

Although the panel has not been connected to an interface card, it is an easy process to connect a PoKeys or Leo Bodnar interface card to the Canon plug. ProSim737, nor Sim Avionics include functionality with this panel.

Purchase Guidelines - Avoid Being Disappointed

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737-800 flightdeck (simulator)

Based on feedback from my previous journal post, I decided to write a few lines dealing with what we, as simmers and virtual pilots, should expect from manufacturers and sellers.  This post is more directed to those entering the hobby rather than experienced builders; those that have been in the 'game' long enough already know the 'do's and don'ts'.

In comparison to other more main-stream hobbies, flight simulation is relatively uncommon and specialized, and as with fishing, hiking, dog grooming and gardening, a plethora of companies have sprouted to supply the enthusiast with an assortment of “essential” add ons from panels and quadrants to books and magazines.  Some manufacturers are large companies and others small “one man bands”.

'Caveat Emptor'

It is unfortunate, that even in our small community; all potential buyers must be conversant with the term 'Caveat Emptor' meaning in Latin 'Let the buyer beware'.  Nobody is immune from the unscrupulous seller whose only want is to remove the hard-earned cash from your wallet or pocket book.

Since beginning the development of the B737 simulation two years ago, I have come into contact with many companies and individuals; some respectable, reliable and very honest, and others that live in the silt, that swirls around in the bottom of the barrel.

The small number of 'bottom crawlers' (without being offensive towards trilobites and other invertebrates) include not only those that sell reproduction parts, but also those that sell real secondhand aviation parts.  One seller of real aviation parts lists and shows a picture of one item on his website, however, dispatches a different lower quality item. 

Do you have recourse - NO!   Once you have parted company with your money it is is gone forever...... 

Supply, Demand & Payment

One theme common to many suppliers is the time it takes to supply a customer with their product.  This is especially evident when commissioning manufacturers to produce and supply hardware associated items such as yokes, panels and the like. 

Suppliers always want their money up front and nearly always promise supply forthwith.  Unfortunately, this rarely happens.  Any number of excuses are promulgated: I’m busy, too many orders, lack of staff, waiting on parts, postal service delays, sickness – and the worst of all - no contact despite e-mails being received..

This is not to say that all companies and individuals selling flight simulation products have a poor reputation; this would be incorrect.  There are many sellers that provide first rate service that cannot be bettered.  It is unfortunate that all businesses do not subscribe to this philosophy.

Forums

It is an easy task to “troll” through one of several flight simulation forums and read the common threads evident in many of the posts published by disgruntled customers.  If a common theme is duplicated in several threads, such as: delay, problems, glitches, bad communication or minimal contact, then why expect your experience to be different.

"past experience is a prime indicator to future performance".

Do Not Accept the Risk

I think anyone who has been involved with the industry for any length of time, has a horror story to tell.  

It ceases to amaze me that many potential buyers that have read the threads on the forum and asked the correct questions, still proceed with an order and send full payment to an unscrupulous company or individual.  It is almost as if they want the product so badly that they are happy to accept the risk!  Then, after they have been let-down they post their story to a forum.  

Unfortunately, this behavior only goes to strengthen the resolve of the suppliers that continue to behave in this manner.  If you look at the supplier’s point of view, why should they improve their performance if there is any number of purchasers willing to order and pay for something in advance. 

There is no incentive to change!

The only way the supplier will alter their behavior is if you, the customer, alter your behavior.

I'm not suggesting that a vendor will "run" with your money, but there have been instances of vendors suffering financial problems which culminated in them liquidating their business.  If you have paid in full before production occurs, and a financial problem develops, then retrieving your money will probably be difficult. 

Purchase Guidelines

Before any purchase:

• Do your research.  Know your product and know what you want for your set-up.

• Ask others regarding their experiences with a company or individual.

• Read the forums, learn to use the search functionality on each forum and contact members who use the same item you wish to purchase.

• Ask on a forum whether a manufacturer is reliable, prompt and does good work.  Building a flight deck is a detail thing; it’s not hammer and nails mentality.  Why employ someone who is not into detail...

• Try to only pay a deposit, despite being told otherwise. 

• You are the customer and you have a right (obligation) to ask anything you want of a manufacturer.

• Secure an accurate time-line in writing to when an item will be supplied.

• Ask about a return policy should you not be happy with the items purchased.

• Finally, if the information you are told by several people is identical – then BELIEVE this information and don’t make the purchase. 

Instead, contact the supplier and tell them your concerns and reasons why you will not be buying from them.  Often when you do this, the supplier will alter their behavior to accommodate you.  After all, they want your money!

Guidelines for purchasing real aviation parts

• If an item looks a bargain it generally is not…..

• Always check on return policy.

• Only purchase from E-Bay from sellers with a solid positive feedback rating.

• Pay via PayPal if possible as PayPal will provide buyer protection.

• If the advert states "not checked, unsure if working or similar", then expect the item will be broken.

• Assume nothing.  Assumption is the "Mother" of all ClusterFucks".  A "CluserFuck" is a military word meaning multiple problems (see definition a bottom of page).

• Pay a little more and purchase ONLY from reputable, reliable and honest dealers.

Have I been caught before – of course!  Will I get caught again – not likely, hopefully not....

Definitions

'CluserFuck' - Military term (mainly American) for an operation in which multiple things have gone wrong. Related to 'SNAFU' (Situation Normal, All Fucked Up") and 'FUBAR' (Fucked Up Beyond All Repair).

In radio communication or polite 'conversation (i.e. with a very senior officer with whom you have no prior experience) the term 'clusterfuck" will often be replaced by the NATO phonetic acronym 'Charlie Foxtrot'.

SISMO Soluciones - Avionics Review: My Negative Experience

I initially wasn't going to document my negative experience with Sismo Soluciones as many simmers use SISMO products and are fiercely loyal to this company.  This post has sat unpublished for close to 10 months until a friend convinced me otherwise, saying that bad reviews can be beneficial, especially to new simmers who are undecided on what and whom to purchase from.

This is the first negative review I have written and in doing so realise that I will no doubt annoy some people, especially loyal SISMO customers.  My aim is not to annoy, intimidate or create malicious rumours.  Rather, it is to share with others my factual experience with this company. Due to the negative nature of this review, it WILL NOT be posted to any forum.

I purchased the following units from SISMO:

• ADF radios (2)

• Transponder / ATC radio

• Audio Control Panel 

• rudder trim module

At the time, I was using Sim Avionics as my avionics suite.

I had issues with: aesthetics, quality assurance and the use of the SC Pascal script.  

When you initially look at the modules offered by SISMO, they do look attractive; however, it's often the small things that count and the panels made by SISMO lack the attention to detail and quality expected.

• This article is a little different from previous articles.  I've made a basic review of the modules, then discussed the issues I had in respect to with the panels/modules.  Finally I've discussed company.

Please note that I use the word panels/modules interchangeably.

Overall Module Construction and Appearance

The modules are constructed from acrylic and painted in Boeing grey.  The use of CNC machining produces a crisp finish resulting in cut-out lettering that is well defined.  This enables the lettering to appear very crisp when the panels are back it.  The buttons and switches used in the panels are machine injection moulded and secured to rotary stems via two small grub screws. The electronics are not sealed pr boxed (such as in CP Flight) but are visible.  DZUS fasteners are not included although holes have been drilled in the appropriate position (although these holes are too small to fit genuine DZUS fasteners).  The backing plate is made from plastic.

Paint Work

The paint work used by SISMO is not of a high quality.  The paint, eith minimal use of the panel, wears thin on the panel beneath the knobs and switches.  The paint also chips very easily and is not evenly applied to include the side of the unit.  Although I don’t know how many layers of paint have been used, I’d suggest it’s minimal.  Minimal paint saves time and expense and does not lend itself to high quality or longevity.

Integrated Backlighting (IBL)

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SISMO ADF unit & FDS NAV1 unit.  Note the difference in backlighting (not seven-segmented displays) and module colour between the two units.  FDS use real aircraft bulbs

SISMO does not utilise real aircraft bulbs for backlighting.  Rather they use a number of strategically placed LED lights.

There are several arguments for and against the use of bulbs and LEDs.  The former provide a realistic throw of light at the correct colour temperature, while LED’s are usually more pin point, require less power to run, and usually appear colder in colour temperature.

The Backlighting on the SISMO modules is reasonable; however there is not an even throw of light across the rear of the panel to allow complete illumination of all cut out lettering.  The panel also does use a light skirt to inhibit stray light from illuminating the outer edge of the modules  The backlighting is powered by 12 volts.  The colour of the LEDS is amber yellow or warm orange.

I had an issue with two LED lights; The LED lights stopped working.  SISMO informed me I would have to repair this myself.  Shortly thereafter, a third LED light failed. This suggests that SISMO may have a quality issue in relation to the LEDS they use (at least in the batch I received).  I have little doubt that the LEDS are inexpensively sourced from China (ROC).

Electronics

The upper panel of the module is attached to the electronic circuitry within the lower section by a backing plate made from plastic.  It should be constructed from metal to aid in strength.  The electronics appear substantial and to be well built (appearance only as I did not bench test the electronics). 

System and I/O Cards

The modules are not standalone devices.  Depending upon your requirements, the modules require connection to various system and sim cards for complete operation.  As an example, to operate the ADF units and rudder trim module requires three GIC connection cards, an Ethernet motherboard card, and three servo-daughter cards – seven cards in total!  

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figure 1: sismo card setup. there are lot of cards

Although there is nothing wrong with this method of operation, it does pose a challenge to find a suitable location to mount the cards.  The cards appear to be constructed to a high standard and are very solid; they do not feel or look like cheap Chinese-made cards.

I’ve included, for interest, a schematic wiring and card diagram of the module set-up for the Captain-side ADF radio. (click the image to enlarge the picture). 

The main Ethernet mother board requires a 5 volt power supply.

Wiring

SISMO provides you the opportunity to either use their prefabricated flat cabling or to wire everything yourself.  I choose the former and this saved a lot of time and frustration (wiring and soldering).  The flat cable packs are each fitted with heavy duty plastic clips for attachment to the cards.  Connection is straightforward and SISMO provide large A3 colour wiring sheets so you know exactly what wire plugs into what card.

If you decide to use the flat cabling, it’s necessary to include in your system a number of additional cards.  These cards, called  Generic Interface Cards (GIC) act as joiners between the different system cards used by the panels. The size of each GIC card is little larger than a credit card. 

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SISMO panels with flat cabling.  There is a lot of cables that need to connect with several interface and GIC cards

Too Many Cards

The amount of wiring and number of cards needed to use SISMO products is ridiculous! 

Using four panels, the interior of the center pedestal is a mass of wires leading to and from various interface cards.  There are far better and easier alternatives available from other manufacturers.  

The Power of Ethernet

SISMO’s product range utilises Ethernet technology rather than USB; this has many advantages over the use of USB. 

According to SISMO literature: 'USB was not designed to carry the volume of information necessary for flight simulation. Although USB is practicable and does work very well, it can on occasion malfunction (drop out), or slow the operation of the intended device by creating a bottleneck for information flow.  Ethernet, on the other hand, has been designed at the onset to allow for high information flows ensuring fast and consistent transfer of information'.

An Ethernet cable is required to link the main Ethernet mother board, either directly to the computer or to a switch (if using two or more networked computers).

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The two tabs overlap the OEM DZUS rails.  You must cut the DZUS rails to allow the module to fit the pedestal

Real B737 Center Pedestal - Not Drop & Fly

An important point to note is that the ADF and ATC radios will not drop directly onto the DZUS rails fitted within a real B737 center pedestal. 

SISMO modules have been designed so that the electronic boards, mounted directly beneath the panel, are flush to the edge of the panel.  What this means is that the panel cannot be placed directly onto a rail, as the electronics board abuts the edge of the rails. 

To allow correct placement in a genuine center pedestal requires that the DZUS rails be cut in the appropriate position.

All the other SISMO modules, other than the ATC and ADF modules drop onto the rails without an issue.  I'm unsure why this manufacturing inconsistency has occurred.

Misleading Information

During my initial research, I asked SISMO if their panels fitted a genuine center pedestal.  I also queried if OEM DZUS fasteners could be used.  Juan Ma (sales) stated that all SISMO panels were DZUS compliant and did fit genuine DZUS fasteners; however, when I told SISMO they didn't fit the rails, Juan Ma claimed he had misunderstood my question due to his poor understanding of the English language - he meant to say no rather than yes.

To utilise OEM DZUS fasteners, you will need to enlarge the attachment holes in each of the panels to enable the fastener to fit into the hole.  A word of caution here – SISMO use plastic backing boards which will crack easily if you are overzealous with a power drill (this is why I suggested, earlier in this article,  that metal be used.

Communication and Support

Support for SISMO is either directly via e-mail or by their dedicated forum.  All e-mails are answered quickly (in English or Spanish). JuanMa and Cristina answered all my e-mails in a professional level.  They are courteous, exceptionally patient, and very helpful; both strive to help you as much as they can.  

SISMO Modules - A Closer Inspection

ADF Radio Module

Initially, you’re impressed when you look at the ADF panels.  The seven segment displays, illuminated in either amber yellow or warm orange are easy to read, well lit, and appear similar to the displays you would see in a real aircraft. 

As you turn the rotary knobs to change the frequencies there is no catching as the knobs are turned, and the push-to-activate buttons move freely.  They do not stick in the down position when depressed. 

Problems

One small issue I immediately noticed, was that the tinted window plate which sits over the frequency display is not secured; as opposed to other manufacturer’s modules that incorporate the plate into the actual construction of the panel.  If you invert the modules the cover plate will fall out of the recess.  I decided this wasn’t a problem; how often are simulators inverted, and securing the plate is an easy exercise.  A small piece of double-side tape is all that is needed to secure the plate in place.

My problems began after roughly four hours of use.  The frequency push-to-activate button was temperamental and would not allow the stand-by and active frequency to be changed with one push; several pushes were required.   The problem was intermittent, but investigation suggested an issue with the clicking mechanism or the button itself.

The next issue to develop was with the rotary knob; turning the knob caused the frequencies to jump digits.  As with the push-to-activate button, the problem was intermittent but, the problem was rectified when you closed and reopened the SC Pascal script.  Perhaps the script needed tweaking.

Knobs and Switches - Poor Quality

I was disappointed with quality of the switches and knobs used on the panel.  The two ADF-ANT switches are made from hand injected low quality plastic; several small injection holes in the plastic are easily seen.   For the minor cost involved, high quality machine-injected knobs could have been manufactured.  

Each of the ADF-ANT switches slides onto and over the plastic circular shaft of the rotary mechanism.  The knob is then secured to the shaft by two grub screws each side of the knob.  It doesn’t take too long for the grub screws to begin to loose their grip on the shaft with resultant slippage of the knob.

Other companies have solved this potential problem by using D-shaped shafts or higher quality rotary switches incorporating metal shafts instead of plastic.  Knobs manufactured by high-end companies use stainless steel shafts and stainless grub screws that screw into stainless sleeves.

• My rating 4/10

Audio Control Panel (ACP/ASP)

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SISMO ACP unit does not look realistic with inexpensive poorly moulded buttons and very stark backlighting.  Note that some of the rectangular buttons are not in alignment.  This unit has been constructed with very poor attention to detail.  Note, the black knob is not a SISMO knob but comes from a 737CL (OEM)

The Audio Control Panel (ACP/ASP) replicates the audio system of the B737 (navigation radios, etc).  The ACP occupies a large piece of real estate in the center pedestal and the ability to turn on and off navigation audio sounds should not be dismissed.

The main ACP switch is of similar construction to the ADF-ANT switches on the ADF module; it is poor quality with injection holes readily observed.  The clear push buttons used to turn on and off the various audio sounds are of low quality.  The buttons are fashioned from clear acrylic and lack detail and definition.  

I was disappointed, that when the ACP unit was fitted onto the pedestal, light from the backlighting seeps along the edge of the panel (to stop this I applied masking tape to the side of the panel to create a light skirt.  I also noted that some of the buttons are not accurately aligned with one another. 

Often it’s the small things that count and push a product to the next level. Clearly this is not a mantra that SISMO adhere to.

I was not impressed with the quality and attention to detail on the SISMO ACP unit; therefore, have decided to convert two real B737-500 ACP panels to simulator use.

• My rating 2-10

Rudder Trim Module

The rudder module incorporates a large knob that is center-spring loaded.  The knob allows the rudder to be deflected in either direction and be recorded in degrees of offset on the scale.  The movement of the defection needle is made possible with the use of small servo motor fitted beneath the module and powered by 12 volts.

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SISMO rudder trim module.  Note the very poor moulding on the knob and colour shift with lighting

The rudder trim knob is poorly moulded and clearly portrays hollow holes left over from the injection process.  For those searching for aesthetics, replacement using a real B737 knob is very easy (if you can find a real knob).

The trim needle, at least on my module, is a little lop-sided.  As with the ACP module, stray light from the LED backlighting is readily seen around the edge of the panel.  Like other SISMO panels, there is no inclusion of a light skirt to stop stray light.

The remainder of the module is aesthetically pleasing.

The rudder trim is one of the modules that is necessary to complete a center pedestal, but unless one is regularly flying with one engine, the module is seldom used.  Therefore; this module from SISMO, even with the irregularities, is a reasonably priced alliterative to some of the more expensive counterparts available (provided a replacement knob is used and light skirt is fabricated).

• My rating 5-10

ATC (Transponder) Module

This is one of the better produced modules from SISMO. 

The switches and knobs are manufactured to a quality at least equal to what other companies produce.  There are no injection holes in the knobs, and turning the frequency knob is very smooth when altering frequencies. The digital read out is crisp, yellow amber in colour, and the tinted window, which falls out easily on the ADF panel, seems to be more secure (although it is the same drop in type).   As with the ADF panel, this panel will require you to cut the DZUS rails if you are using an OEM 737 center pedestal.

As a script was never supplied with this module (SISMO did not send it), I cannot provide information to how well it operated.  

• My rating based solely on appearance is 7/8-10

Reliability and Performance - Software and Modules

Software - SC Pascal Scripts

The modules require SC-Pascal scripts to be installed on the simulator computer. 

The basic script is downloaded from the SISMO website.  A further customised script is needed to configure the modules to the avionics software package you are using (Sim Avionics, Project magenta, ProSim737, Orion, etc) and FSX.  SISMO write the script dedicated to the panels you are using.  To activate the panels you run the executable file when you open a flight session.

SC-Pascal scripts are completely new to me, but a little research indicates that the script is used as a software interface between the actual functionality of the various panels, FSUIPC and simulator software.

Once the scripts are installed and configured correctly, a folder is created in which is stored the config.ini file and the executable script.  The folder and files can be named and stored anywhere on your computer system.   The panels are turned on by activating the executable script (.exe).  

As an option, direct access to the script can be made by adding the executable command to the auto start folder of your computer.  This option automatically starts the modules when the computer is turned on.  The script then runs in stand-by mode until flight simulator is turned on.  This option saves time and repetition by not having to turn on the executable file.

As SISMO utilises Ethernet technology, the various IP addresses of the computer (s) you are using need to be correctly configured to allow communication between the computer and the panels.  This is basic networking knowledge and is relatively easy to learn.

Once the software is configured, the software and modules should function flawlessly.  

Script Problems

I did have some issues with the SC Pascal script freezing when it was initiated.  The script also caused some issues which appeared to cause the ADF radios to incorrectly display frequencies.  To Juan Ma's credit, he did tweak the script, however, the problems remained.

As I know nothing about SC Pascal scripts, I don't know with certainty whether the problems experienced were caused by a script issue, hardware issue, or something particular to my system.  If push comes to shove, my guess is that the problem lay with the SC Pascal script.

I try to keep things simple in my simulator, and running multiple scripts for various panels through several interface cards doesn't exactly fit into this ethos. 

It would be inaccurate to state that SC Pascal scripts don't work, because there are many enthusiasts who have them operating perfectly.  But, I am not one of these individuals.

Note that I was using Sim Avionics.  If using ProSim737 there is an option to use a script or direct drivers within ProSim737.

Quick List - Pros and Cons

PROS

• Fairly accurate 1:1 ratio (or close to)

• Easy to install and use software (knowledge of SC Pascal required if altering software)

• Laser cut and stenciled lettering

• Ethernet technology

CONS

• Plastic shafts on ADF-ANT knobs (should be metal/stainless)

• Poor quality knobs and switches on ADF, ACP and Rudder Trim module

• Average light coverage for LED backlighting

• ADF and ATC modules don't drop directly onto DZUS rails; the rails must be cut.

• Large number of cards needed for operation

• Not DZUS complaint (requires existing holes to be enlarged)

• Plastic backing plate on panels (easily damaged when enlarging holes for DZUS fasteners)

• Light seepage around edge of some panels from backlighting (no light skirt)

• SC Pascal script troublesome and works intermittently.

• Poor quality paint work

Considering the above, the panels are expensive.

Final Call

The modules are ideal for the budget-conscious flight simmer.  This said, a potential user must have knowledge to troubleshoot problems.

The lack of quality knobs, switches and poor attention to detail detract aesthetically, while the large number of cards that need to be installed can make installation challenging.  Three failing LEDS and problems with the frequency selector switch on the ADF radio panel may point to quality assurance issues.  The use of Ethernet over USB is highly commended and may reduce information bottlenecks.

My rating for the software is 4/10 (The supplied scripts didn't work with my system, which at that time was Sim Avionics and not ProSim737).

My overall rating for the modules is 3/4/5-10 (based on fitting issues, quality of knobs, poor attention to detail, poor painting, no light skirts and temperamental frequency selection switches on ADF).

Please note that this review is my opinion only and is not endorsed.

POST SCRIPT: - July 15, 2012 - RETURNED MODULES TO SISMO REQUESTING REFUND

I have returned all the panelss, cards and wiring  o SISMO for a full refund (minus freight).

Initially, SISMO offered me 10% of the value of the products purchased (this included the interface cards that had never been used).  

SISMO stated that the return period had been exceeded, and any products returned would be treated as second hand units.  It didn’t matter that SISMO had not, at that time, sent all the appropriate SC Pascal scripts to ensure correct operation of the modules.  

The writing of the SC Pascal scripts was delayed close on 2 months after I received the modules, and when received, the scripts didn't funcyion as intended.  Excuses were; staff holidays, workloads, Easter break, and awaiting confirmation from another company to facilitate operation.  

Upon receipt of the returned items, SISMO claimed that many of my issues were incorrect or not relevant.

• They claimed that the modules had been damaged.

• They stated that I had broken the LEDS (I told them the LEDS were not working when I received the parcel).

• They claimed I had disassembled the units and damaged the paint and screws.

• They claimed I had re-painted portions of the units.

• They claimed sticky plaster was attached to one of the units. (this is correct as I used tape to secure the wiring & also to create a trial light skirt)

• They deducted from my refund, Spanish import duty and inspection fees (returned the goods to Spain).

• They claimed I did not include paperwork (which I did). 

• They stated that as the ATC RADIO module was discontinued, a refund was not possible.  At the time of purchase they did not inform me this panel was discontinued.

I'm not going to go into a long account to what has transgressed.  But, I will say that this company cannot be trusted…..They promise the world to you, but if you aren't happy with the products, they provide every excuse possible to NOT provide an adequate and reasonable refund.

For example, when I reported the failure of the LEDS to SISMO, their response was 'they worked when they left the shop'.  They did offer to replace the LEDS but, at my shipping expense (which was expensive).  They also offered, because of the inconvenience caused, a discount on further purchases.

It should also be noted, that in my initial correspondence with SISMO, I asked whether their panels would drop directly into an OEM B737 center pedestal.  Juan Ma stated 'YES'.  However, on receipt it was discovered that the modules were too large to fit directly onto the pedestal DZUS rails.  I queried Juan Ma from SISMO on this; he stated that it was a language misunderstanding.

Juan Ma understood perfect English when it came to avoiding a refund of purchase money.

Legislation, PayPal and Delays

Spanish legislation states that every purchase has a 7 day cooling off period, in which a return and refund can be made.  PayPal policy states you have 45 days in which to make a claim.  EU legislation states that refunds are possible if items do not function correctly - within a set time frame.

Without a working script for Sim Avionics (which took two months to receiveve), how can testing of panels occur.  Because of the approximate two month delay on sending operating scripts to me, all options available to me had expired.

I cannot help but think that SISMO delayed the sending of the scripts so as to provide a reason for NOT refunding 100% of the purchase price.

SISMO Solicones appears to be a company that will ONLY support and stand by their products if you continue to use their products and not complain, or attempt to return them.

If you ask for a refund due to faulty components, components that don't function, or scripts that don't function correctly, then expect NOTHING, or at the very least, a minimal refund (and you will have to fight to get this refund). 

What you can expect from SISMO, is e-mail after e-mail informing you that you have no right to a refund, that you have damaged the items, and that you did not follow SISMO policies, etc, etc.

After many e-mails, I succeeded in gaining a E400 Euro refund for an initial E1400 Euro outlay.

I'm sure there are many happy customers using SISMO products; however, I am not one. I do not recommend SISMO Solicones. 

Their products are of poor quality.  The attention to detail that is required (and expected) when replicating an aircraft panel is very poor.  And finally, their customer service is dismal if you are seeking to return an item.

In my opinion, it's VITAL that a company standby and support their product-line, and this includes refunds if the product (for whatever reason) is not suitable with your simulator set-up.

If you search the Internet, you will find very few comments regarding SISMO, other than company endorsed reviews on forums that are supported by manufacturers and resellers.

If you are searching for quality avionics panels, look no further than Flight Deck Solutions or CP Flight. 

These two companies are reliable, produce quality products and provide exceptional after sales service.  They also offer a refund if not 100% satisfied with their product.  Whatever you do, don’t spend your money on inferior products from SISMO! (my opinion only).

• This review is rather negative towards SISMO Soluciones.  I have 'toned down' my anger to this company considerably in an attempt to produce a balanced and accurate review.  Please understand that this is my experience with this company.  Your experience may well differ. 

Feel welcome to make comments, either good or bad in the comments section.

Updated and Amended 15 April 2020

Update

on 2015-08-27 00:15 by FLAPS 2 APPROACH

I wasn't expecting such a response to this post.  Nor was I expecting SISMO Soluciones to link this negative review to their website, face book account, and on several other prominent forums.

Whether an individual likes or dislikes a product based on aesthetics and functionality is subjective; what I dislike, another simmer may like very much.  I know several simmers that use SISMO and are very happy with the product. 

My main 'gripe' with SISMO, apart from poorly produced products, is their no questions non-return option should you be in the former (dislike) category.

Whatever transpired between myself and SISMO is water under the bridge.  If a company stands by their products they offer a no questions return policy.

I have since heard, based upon this review that SISMO may be taking legal action against me for what I have written.  I have told the story as it unfolded and refuse to retract what has been written on an independent and non-industry supported website. 

• This is one of the purposes for this site - unbiased and honest appraisal of products I have used.

Thanks for your lively comments.   Cheers

Replacement OEM 737-500 Throttle & Center Pedestal - Conversion to NG Style

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737-300 throttle quadrant with old style paddle-style stab trim levers

The last few months have seen quite a bit of activity regarding the throttle quadrant and center pedestal, which has culminated in me selling my former 737-300 series throttle quadrant and pedestal and replacing it with an another unit from a late series 737-500 aircraft.

Brief Recap

In late 2012, I decided to convert the 737-300 throttle to full automation.  A dilemma I faced was whether to keep the throttle unit as a 300 series throttle with the attached two-bay pedestal, or do a full conversion to make it similar to the Next Generation. 

After careful consideration, it was decided convert the throttle quadrant.so it appeared as close as possible to the Next Generation.

Stab Trim Switches

One of the biggest differences, apart from thrust lever handles, between early model throttle units and the Next Generation units is the stab trim cut out switches.  On the earlier 300 series units, the switches are paddle / lever style switches while the Next Generation uses toggles and T-Locks.  T-Locks are a safety feature and sit beneath the toggle switches and are spring loaded; the pilot must push down the T-Lock to activate the toggle.  

To convert the trim switches requires cutting out the old switches and fitting new reproduction Next Generation switches.  This is a major task requiring precision work.  Although reproduction switches can be made, the reproduction T-Locks don't operate as the real T-Locks should.  I did search for some genuine T-Locks and toggles, however, my search was fruitless as these parts appear to be reused by airlines (or recycled).

Replacement 500 Series Throttle Quadrant & Three-Bay Center Pedestal

A friend of mine informed me that a late model 737-500 throttle quadrant was for sale.  This unit was in better shape than my existing throttle, included the genuine Next Generation style stab trim switches complete with T-Locks, and also had a three-bay center pedestal.  It appears provenance was shining on me as the new throttle appeared for sale a day before the stab trim switches were about to be removed (with a metal cutter...)

The throttle and center pedestal were purchased (you only live once!) and the 300 series throttle sold to an enthusiast in Sweden.

Next Generation Conversion

To bring an earlier style throttle and center pedestal to appear similar to a Next Generation throttle quadrant requires, at a minimum:

• Attachment of a Next Generation style throttle lever shroud to existing aluminium levers;

• Removal of TOGA buttons and relocation to bring design in-line with a Next Generation (the buttons are identical, but the housing is different);

• Possible replacement of the stab trim switches;

• Painting of throttle housing and center pedestal from Boeing grey to Boeing white; and,

• Painting of all throttle knobs from Boeing grey to Boeing white.

The biggest hurdle is usually replacing the trim stab switches, however, as these are already present on the new throttle, and are the Next Generation, considerable time and expense was saved in not having to replace them.

Main Differences - Next Generation & Classic

The Boeing airframe that most people associate with today begins with the 737-200 and ends with the 737 Next Generation.  In between we have the classics which refer to the 737-300, 400 & 500 series airframes. The 737 Next Generation series includes the 737-600, 700, 800 & 900 series airframes.

The main differences between a classic and Next Generation throttle quadrant are:

• The stab trim switches are slightly different; the classics having two flat levers while the Next Generation has toggle-style buttons with T-locks;

• The throttle thrust lever handles; the classics are bare aluminium and the Next Generation is white aluminium that is ergonomically-shaped.  The TO/GA buttons are also positioned in a different place on the Next Generation.  The knobs (handles) on the levers are also coloured white rather than off-grey;

• The method that the throttle thrust levers move during automation.  The classics move both thrust levers together when auto throttle is engaged.  The Next Generation moves each lever individually in what often is termed the throttle dance (this is due to the computerised fuel saving measures incorporated in the Next Generation);

• The spacing (increments) between each flap lever position is identical in the Next Generation, but is different in the earlier series throttles;

• The center pedestal in the classics is either a two-bay pedestal (early 300 series and before), but more likely a three-bay pedestal.  The Next Generation always has a three-bay pedestal.  Base materials for the center pedestal are also different - aluminium verses a plastic composite material;

• The speedbrake knob is very slightly more elongated on the Next Generation unit; and,

• The telephone, circuit breakers and mike assembly differ in type and location

Next Generation Skirt - Thrust Levers

Boeing when they designed the Next Generation style throttle didn’t design everything from new; they added to existing technology.  All Next Generation throttles utilise thrust levers which are identical to those of earlier units.  

Boeing designed a shroud or skirt that attaches over the existing thrust levers encapsulating the older thrust levers and sandwiching them between two Next Generation pieces.  The assembly is made from aluminium and is painted white.

The TO/GA buttons are located in a different position on the Next Generation units, although the buttons used are identical.

To alter the position of the TO/GA buttons you must detach  the small aluminium box from the 300 series thrust levers, remove the TO/GA buttons, and then re-solder the buttons in the appropriate location on the new unit.

I did not make the Next Generation skirt for the thrust levers, but rather had fabricated, from design specifications, a reproduction skirt.  The skirt is produced from aluminium and replicates the dimensions of the Boeing part.

Time-line, Functionality and Conversion

The throttle is initially being converted in the United States.  The advanced work (automation) will be done by a good friend in California, and then I will follow on with more mundane tasks.

The replacement unit will feature several improvements which will allow: full motorized functionality, full speed brake capability, accurate trim tab movement, alternate trim wheel spin speeds, correct park brake release, trim wheel braking and several other features. 

I want the functionality of the throttle to be as close as possible to that found in the real aircraft; therefore, the methods used to ensure this functionality will be slightly different from the norm.

When the throttle is fully functional and tested, I'll publish a post providing further information and detailed photographs of the various functions.

It is hoped everything will be completed, and the throttle and pedestal installed by late May 2013.  The next month or so will be quite exciting.

Two-bay Pedestal Will Be Missed

I know I will miss the narrower two-bay center pedestal.  A major advantage that will be lost is the ease in climbing into and out of the flight deck; the two-bay provided more room between the pedestal and the seats.  At some stage, I probably will need to install J-Rails because the seats I'm using are fixed-claw feet Weber pilot seats; J-Rails will be needed to allow lateral seat movement.

BELOW:  Montage of several images showing main visual differences between 737-300 classic series throttle quadrants and the 737 Next Generation. The 737-300 throttle is my old throttle but, the Next Generation throttle quadrant belongs to a mate of mine.

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Montage of several images showing main visual differences between 737-300 classic series throttles and the 737 NG style throttle units. The 300 series TQ is my old throttle unit but, the NG Throttle quadrant belongs to a mate of mine