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How to fly the NGX with two engine failed?

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Hello everyone, for fun I have failied not one, but two engines on my NGX. However, I am left with no way of flying the plane! All the hydraulics are dead. How do I fly the plane in this state?

Kashif Eizdi

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Venturing a guess, but start the APU. I'm not at my computer, but check the FCOM manual. I may be wrong! Good luck!

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Hello everyone, for fun I have failied not one, but two engines on my NGX. However, I am left with no way of flying the plane! All the hydraulics are dead. How do I fly the plane in this state?

 

Kashif Eizdi

I'd too have to look at the FCOM to fully remember/know, but the top left corner of the lower overhead has reversion controls.  Get the APU up, and take a look in to that panel.

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How do I fly the plane in this state?

See these two NTSB Reports. Maybe there is some useful information in them.

 

1. http://libraryonline.erau.edu/online-full-text/ntsb/aircraft-accident-reports/AAR78-03.pdf

 

2. http://lessonslearned.faa.gov/ll_main.cfm?TabID=1&LLID=40&LLTypeID=2

 

Number 1 is an accident report involving a DC-9 and Number 2 is a factual finding involving a 737.

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The FCOM won't help because without hydraulics the real 737 flies in manual reversion.

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Thanks for the reports Michael.  The second one was very interesting and I may go back to the first when I'm not so tired.

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Well the first thing is to fly the airplane and commence a descent to stop the speed from bleeding away. Then you'd start the APU. Then you'd refer to the QRH, "Loss of Thrust on Both Engines". It's a very long list of actions.

 

It will tell you to try and restart the engine(s) in several ways, for that you have to pitch for airspeed of 275 (above FL270) or 300 (below FL270).

 

And surprisingly enough, it never tells you to "plan to land at nearest suitable airport".

 

In RL the PF would just fly and the PM would go through the QRH and its items.

 

EDIT: Regarding the loss of hydraulics, you'd go to the QRH "Manual Reversion" (loss of both hydraulic systems) which will indeed tell you to land at nearest suitable airport. There's a series of systems that won't work. You'd have to plan to land with Flaps 15, use alternate flap/gear extension etc.

 

Also the yoke must get really hard (something similar to the wheel of a car when the engine is off) but the airplane is still flyable if the pilot has some "muscle". The 747 wouldn't be flyable upon loss of all 4 hydraulic systems (see JAL 123). The rudder has its own standby hydraulic system so I guess you would operate the pedals just as usual.

 

The DC-9/MD-80 is "designed" to be flown in manual reversion, so to speak. The pilot controls "tabs" that in turn deflect the ailerons in the opposite direction. It's a really interesting system.

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Also the yoke must get really hard (something similar to the wheel of a car when the engine is off) but the airplane is still flyable if the pilot has some "muscle". The 747 wouldn't be flyable upon loss of all 4 hydraulic systems (see JAL 123). The rudder has its own standby hydraulic system so I guess you would operate the pedals just as usual.


The 737 has balance tabs and balance panels to reduce the pitch and roll forces for the pilot. So while it does require a little more muscle the main problem is the increased backlash in the controls with no hydraulic assistance. As you say, standby hydraulics allows the rudder to be moved (no manual reversion).

 

You can fly the NGX without hydraulics but control movement is very limited.

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Hi Kashif

 

Double Engine Failure has to be dealt with in different ways depending at what stage of flight you’re in.

We practice it every three years, Double Engine Failure and Ditching after departure (Appx 3000ft) and Double Engine Failure (Appx 6000ft) with an air Turn back and landing. Both engines have severe damage (Hudson River Scenario)

First things first, whenever you have loss of thrust fly the up speed, this will give you your best glide range (Approximately 3nm per 1000ft for a 60 Tonne 737)

 

 

The first thing that you’ll notice/have is a total loss of AC Power. That’s a list as long as my arm regarding significant equipment you’ll no longer have and you’d have to action half of the QRH which would presume electrical power in most of the situations so get that APU started to restore power ASAP.

 

 

As you no longer have any hydraulic power (until the APU is up and running) the ailerons and elevator have to be controlled manually (Manual Reversion) I have no idea how/if this is simulated within PMDG. In the simulator its bloody hard work and you have to trim manually (Total loss of AC Power) until you can get that APU running.

 

 

Whilst the APU is booting up that’s when you have to make your decision. Do you ditch? Can you land? Lots of different scenarios where you might not have time to dig out the QRH.

 

 

The QRH Loss of Thrust On Both Engines would then be actioned. This involves memory items to complete (Up to the Dashed Line in the QRH) Depending on where you had your Double Engine Failure you might not have time to try multiple restart attempts. Boeing presume you’re at Cruising Level and not at 3000ft after departure at 220kts. It’s also worth noting that repeated attempts at relighting the engines following catastrophic damage (eg seeing no N1 or N2 rotation) is a futile distraction.

 

 

Once the APU is put online and electrical power is restored you’ll gain more control. If you can start one or more of the engines follow the rest of the Loss of Thrust on Both Engines NNC. If you can’t start either engine there is no checklist for gliding a 737, Loss of Thrust NNC presumes you can at least start one of your engines.

 

 

You’d hopefully attempt to land on a runway and there really are no rules, do whatever you can to land it. If you don’t think you’ll make a runway take a look at the Ditching NNC in the QRH. Again this QRH presumes you’re in powered flight and have plenty time to action the QRH.

 

 

It’s worth noting with what we call “no time available” situations (Less than 5 minutes before landing/ditching) you do have to act a little more on instinct and less on set checklists and procedures, the QRH can however offer some structure.

 

 

Sorry I side-tracked a bit. I hope you’ll find this information useful. It looks a bit beyond the books and into how we’d actually deal with flying with no engines!

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you do have to act a little more on instinct and less on set checklists and procedures

 

I interpret this action to be based on trained-instinct. This is how the military trains for combat: Train, train and then train... and when it happens improvise like heck.

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I interpret this action to be based on trained-instinct. This is how the military trains for combat: Train, train and then train... and when it happens improvise like heck.

 

Pretty much it. There is very little guidance regarding unsuccessful relights of both engines after a double engine failure. At a low altitude it's an exercise of maximising survivability and minimising third party fatalities. Thankfully an extremely unlikely event and if it does happen we can learn from people like "Sully" Sullenberger and implement such scenarios in the simulator to practice!

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