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-   -   Dead Stick landings in jet transport aicraft (https://www.pprune.org/tech-log/583448-dead-stick-landings-jet-transport-aicraft.html)

sheppey 25th Aug 2016 06:48

Dead Stick landings in jet transport aicraft
 
https://en.wikipedia.org/wiki/Deadstick_landing

Browsing the aviation internet and found this interesting explanation of the term "Dead Stick Landing."

Also displayed were known instances of dead stick landings in jet transport aircraft. The list omitted to mention Garuda Flight 421, a Boeing 737 that lost all engines power in a huge thunderstorm and was forced to ditch flapless in the Bengawan River, Indonesia on 16 June 2002. https://en.wikipedia.org/wiki/Garuda...sia_Flight_421


Losing all engines for whatever reason, over the sea or land, is every pilot's nightmare. Despite this risk, it is not a priority training exercise in current simulator training by major airlines. With no shortage of evidence linking automation dependency as the leading cause of degradation of manual flying skills, it seems strange the subject is not considered a serious enough problem to frighten Regulators or Operations Departments into action. Pity about that. After all, loss of all engines means the pilot has only one go at forced landing successfully. You can't go-around if you stuff up.

Check Airman 25th Aug 2016 07:06


Obviously not considered a serious enough problem to frighten the Regulators into action.
Not the case at all. To lose all engines in a modern transport jet...

1. ...is EXTREMELY rare.

2. ...will have an outcome that is largely dependent on luck. A transport jet isn't a 172 that can glide forever, at a very slow speed, and can stop in a confined space such as a narrow, straight stretch of road. You'd pretty much need to be at just the right hight relative to a VERY long runway in favourable conditions.

You're likely to have degraded control authority, an impressive sink rate, no way to dissipate excess energy, a longer gear extension process, more than usual drag with the gear down, and little or no chance for a second option if one action isn't the correct one. In short, you've got to get everything right the first time, in a situation that is completely unpredictable and which has never been flight tested. If the stars don't line up just right, you're likely to die.

In the sim, it may be trained, but not tested. Personally, there are other failures which are far more likely, that are fatal if mishandled. I'd rather spend my sim time on those scenarios.

donpizmeov 25th Aug 2016 07:15


If the stars don't line up just right, you're likely to die
Not this black duck pal. They are still just aeroplanes. Forced landings are forced landings. I will just move a bit more dirt or water on contact.

Dan_Brown 25th Aug 2016 07:36

don....

Correct, you bet me to it.

A37575 25th Aug 2016 07:48


Personally, there are other failures which are far more likely, that are fatal if mishandled. I'd rather spend my sim time on those scenarios
That wasn't the opinion of the pilot who dead sticked the Air Canada Boeing 767 (The Gimli Glider event). During his speaking tours after the event, he said he wished Air Canada had given him at least one practice dead stick landing in the simulator to give him the skill and confidence to pull off that successful forced landing.

Pilots are exhorted ad nauseum to hone their skills of Threat and Error Management, CRM etc during simulator tests. A dead stick landing has all that rolled into one package. A crew can learn more about those skills in real (simulator) time than spending hours listening to boring lectures and Power Point presentations on TEM and CRM and similar buzzwords of the day

Goldenrivett 25th Aug 2016 07:51

Never give up!
 
Hi Check Airman,

2. ...will have an outcome that is largely dependent on luck.
I don't agree and I don't think Jeppesen thought Capt. Sullenberger's success was largely down to luck either.

http://ww1.jeppesen.com/documents/co...Apch_Chart.pdf

edit:
https://en.wikipedia.org/wiki/Air_Transat_Flight_236

ehwatezedoing 25th Aug 2016 07:55

Any stats about real lost of engine right at V1 versus dead stick landing !?
(all type of multi engine)

Why doing one add nauseum and not the other :confused:

FlyingStone 25th Aug 2016 08:18

1. Agree on not examining all-engine out scenario, but an opportunity to practice here and then would be more than welcome. As far as I know, at most outfits, it's limited only to initial type rating training...

The ditchings in transport category aircraft result mainly on luck and only if you are very lucky, the abilities come in play. Just add thick fog to Hudson scenario, or put that Gimli 767 at the limit of ETOPS range somewhere over the ocean at night. How would have that ended even with the best pilots in the world?

2. Of course not all engine failures on takeoff occur at V1. But it's the most tricky moment for it to fail, since you can't reject the takeoff and at the same time you are at very low speed and still on ground or at least in the rotation phase. You don't think we should waste the valuable sim time for engine failures at 5000ft with 250kts and AP already engaged?

Airmann 25th Aug 2016 08:21

In the last 40 years or so there have been more successful dead stick landings than unsuccessful ones in commercial aircraft.

FullWings 25th Aug 2016 10:40

In a modern jet, clean at best glide speed, you probably wouldn’t notice much of a difference between all engines at flight idle and failed. It certainly wouldn’t be an alarming sink rate.

Gear down with some flap will be different from normal on the approach. You can stabilise and fly a steeper glideslope using speedbrake and/or speed to control it or come in fast on a standard profile with the speed reducing. Both work and are appropriate in certain circumstances.

I agree it’s a useful learning (not checking) exercise in the sim if you’ve got time but realistically, things like unreliable airspeed, GPWS, windshear, low-fuel ops, runway contamination, etc. give better training value as they are much more likely to be experienced on the line.

Mad (Flt) Scientist 25th Aug 2016 13:24

A caveat on doing it in the sim: if the sim was not intended by design to support this kind of flight condition, then there may be no guarantee that it will reproduce the actual aircraft characteristics, whether flight behaviour or systems.

To the best of my knowledge there are NO sim data standards that would ensure appropriate flight performance - so you could easily get a misleading behaviour. And there's no guarantee that the systems behaviour will be what you might actually see "for real".

DaveReidUK 25th Aug 2016 14:30


Originally Posted by sheppey (Post 9485104)
Losing all engines for whatever reason, over the sea or land, is every pilot's nightmare. Despite this risk, it is not a priority training exercise in current simulator training by major airlines.

Risk has two elements: hazard severity (i.e. consequences) and likelihood of occurrence.

It's the combination of those two factors that determines what mitigation, if any, is appropriate, not just either on its own.

Dan_Brown 25th Aug 2016 15:01

Mad

Agree with you there. Until the actual aircraft is for E.G.,dead stick landed or deep stalled, there is no accurate data to insert into the sim software for these scenarios.

galaxy flyer 25th Aug 2016 15:10

The F-16 community has had a number of successful dead stick landings--glide ratio is probably a bit worse than a transport, as the wing loading is slightly higher. One landed at a Chicago area airport and video was certainly interesting.

Gums might be around, our resident expert in all things FBW and F-16

GF

FullWings 25th Aug 2016 15:24


A caveat on doing it in the sim: if the sim was not intended by design to support this kind of flight condition, then there may be no guarantee that it will reproduce the actual aircraft characteristics, whether flight behaviour or systems.

To the best of my knowledge there are NO sim data standards that would ensure appropriate flight performance - so you could easily get a misleading behaviour. And there's no guarantee that the systems behaviour will be what you might actually see "for real".
Understood but I would be very surprised if the aircraft was significantly different in any important way from the sim. If the model is realistic enough for general handling and engine failures on a ZFT conversion, then where are the problems?

You’re well within the tested flight envelope, as opposed to deep stalls, transsonic dives, spins, etc. It’s the same airframe just lacking in thrust. Makes the sums easier: just lift, drag and gravity now!

nick14 25th Aug 2016 16:06

We do them regularly following an incident in Rome.

lomapaseo 25th Aug 2016 16:59

I happy to see in the data some successful dead stick landings.

Agree that there are others not so successful, but what is the difference that training could have made the difference?

Is it simply the experience in a practice scenario or is it the luck of the highly variable last seconds?

From my view a lot of the lack of success were things like catching a tree, water or car with one wing and setting up a cartwheel.

APU_inop 25th Aug 2016 17:14


Understood but I would be very surprised if the aircraft was significantly different in any important way from the sim. If the model is realistic enough for general handling and engine failures on a ZFT conversion, then where are the problems?

You’re well within the tested flight envelope, as opposed to deep stalls, transsonic dives, spins, etc. It’s the same airframe just lacking in thrust. Makes the sums easier: just lift, drag and gravity now!
The thrust is not the only difference. You've depleted the hydraulic pressure on the 737 by the time the flaps reach 5 and you're left on manual reversion, need for alternate flap extension, standby electrics and manual gear extension.

If you're high and able to start the APU, it's doable. If from a low altitude, things get quite interesting. We practice this from 1500' agl just after takeoff once every couple of recurrents and even when prepared for the double fail, it's not as easy as chopping the throttle and diving like on the 172 or like when in a glider. A tin-can in 190kts without any brakes demands quite a good field to be put down on in order not to kill most people in it.

tdracer 25th Aug 2016 18:05

As a rule of thumb, we've long assumed you have a glide range of around 100 miles after an all-engine power loss at cruise, although obviously a heavy aircraft at 30k isn't going as far as a light aircraft at 43k. If you're over land, that will generally give you some options of where to put it down.
I'm a bit surprised that an all-engine power loss isn't normally trained for since it's something we design for (Ram Air Turbines, 30 minute batteries, etc.) at the aircraft level - even if it's classroom stuff such as the best glide speed.
Prior to Sully's little adventure in the Hudson river, I remember a debate over the value of rafts and life vests on jet aircraft since there had never been a successful ditching of a big jet (although to be fair, the only attempt I'm aware of was the Ethiopian 767 hijack, and that's not a very good data point since the hijackers were apparently fighting the flight crew during the ditching attempt).

Welle 25th Aug 2016 18:12

Good Training!

As a TRE in our company i try to give an all engine out landing at least once a year to my crews - if time permits after the check or during the recurrent training.
good way to build up some confidence and think about "what if."
Welle


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