Gliding Large Aircraft
 

In the past 14 months, there have been three well-documented crash landings by large aircraft flying on reduced or nil power. One was amazingly successful and it is probably no coincidence that "Sully" is also a sailplane pilot.

Briefly the background to my own career. 40 years as a professional. Began flying in RAF becoming QFI including "instructing instructors" at Central Flying School, and later a C130 Hercules conversion instructor. Then in civil life, IRE/TRE/Line Training Captain at various stages. Moreover, 50 years as a glider pilot with 3 diamonds.

Now glider pilots know that it is essential to "fly the energy" and that "stretching the glide" is not usually a recipe for success. If a landing away from an airfield - and field landings are part and parcel of the sailplane pilot's flying - it has to be planned carefully and it is vital to land the glider under control rather than "flop" on to the ground in a semi-stalled position.

In the old days of Spitfires, Hurricanes, Hunters, pilots regularly practiced "dead-stick" landings and when it was needed for real, the success rate was often high. When instructing on the Varsity (a largish twin piston) I used to entertain my squadron commander during routine continuation training. The boss would throttle back both engines at say 8,000 feet and enjoy seeing me glide the beast back to the airfield. So it can be done. (Pete Sawyer -are reading this?) But this was not a routine training exercise.

In the airline world, there was NEVER any dead-stick landing training. Aircraft WILL glide well. For example, during standard power-off descent from altitude 2½ to 3 miles per thousand feet are achieved. But of course, we can't train for power-off descents right down to the ground except in the simulator.

Recent events have not always given pilots time to do things as "per sailplane" and the scenario has developed very quickly. However, I really think that there is a case for some investigation into simulator glide training. There are plenty of airline pilots who are also competent sailplane pilots. These would be the people to look into what is and what is not possible and perhaps devise some training regimes.

Jack Harrison

In the airline world, there was NEVER any dead-stick landing training.

Come and sit in on one of my simulator conversion sessions.:ok:

Regards,

Old Smokey

Hi Jack,

Dont know of an airline that formally includes glide approaches to touchdown in the training syllabus. But most pilots get to have a go during spare training time at recurrrent SIM sessions. I have done it three or four times now, and like you say it's an excellent training exercise. The A320 is a beautiful glider and the SIM sideslips very nicely.

I would like to see a SIM with visuals suitable for practice ditching at sea with significant swell and wind. This would be a very challenging exercise.

And wouldn't it be nice if Airbus would hot-wire the left landing light to the batteries so that if someone does ditch at sea at night with nothing but the RAT for emergency electrical power he might have a chance in hell of pulling it off. In this situation the radar altimeters are lost, at best we would have area QNH, and the only external light is the crew torch through the window. Airbus should revisit the design.

Cheers

jackharr
 

Could not agree more. In 25 years of flying twin engined jets for various UK companies, I can only remember one sim session that seriously covered this situation - coincidentally shortly after the Azores A340 incident.
Nothing was ever covered in the manuals but a few 'unofficial' bits of paper used to circulate with, sometimes conflicting, advice.
I believe the manufacturers have a part to play as well - rather than assuming that a double engine failure will always be resolved with a successful relight!
For most pilots, who are not glider pilots and whose light aircraft training might be in the distant past, finding oneself with no power will be a big psychological shock. I suspect this is where the glider pilot is at a big advantage since he is not in such unfamiliar territory. Simulator training (and not just once or twice) will help redress this balance as well as giving practical experience.
Some incidents, like the 777 at LHR and perhaps this latest one at AMS occur at low altitude, giving very little time. Others, such as the Hudson River, allow planning time and, depending on aircraft type, at least some reconfiguration. Type training should include in-depth discussion of this scenario and of the effects on speed and glide angle of gear and flaps (if available). CRM has a huge part to play in a successful outcome of course.
The engine out scenario needs revisiting regularly. It does happen and both airlines and and manufacturers need to come out of denial.

We actually covered that in our 3 year recurrent cycle and often did it in the spare time at the end of a session as well. It is fun and great training. And yes, my old glider flying instincts actually helped there.

In view of knowledge gained in later years on the subject of cylinder shock cooling, an extended throttled back glide with radial engines would not have been conducive to good airmanship in terms of engine handling.
Of course that is being wise after the event. At Butterworth in Malaya in the Fifties, the resident RAAF Dakota had an alarming number of engine failures over a three month period. The fault was traced to the squadron QFI who would rapidly close one throttle after take off to simulate an engine failure and leave the throttle at idle instead of zero thrust. He was tasked with conducting recurrent training on squadron crews and this included simulated engine failures by the dozen. It was this abuse of the engines that eventually led to real engine failures.

Over the years I have done it or watched it in BAC 1-11, DC-10, and A320 simulators - the last as part of the conversion syllabus in a forward-thinking airline. It is not part of the Airbus type rating course... perhaps it should be!
TP

Did it regularly in 7 years of sim sessions on 757/767, it helped to aim for staggered runways like MAN for some wriggle room:}

We did periodically warm the engines on the way down in the Varsity, but my original posting was long enough as it was without going in to such nitty-gritty details.

Jack

Sounds like BCAL

All Eng Inop included in type conversion and in recurrent training TWICE in last 6 years. And I think I am right in saying that our lot (B757/767) include this tri-annually.

Can't recall now (retired over ten years ago) but I think we might have done all-engines out (BAe146) as a sim drill but only for the purposes of practicing multiple relights. Certainly, I never remember doing all-engine out right down to the ground with one minor exception. The instructors used to like to play sometimes at the end of the session and leave you with just one outboard engine working. The 146 was virtually impossible to fly on one and I certainly would finish up doing the last 100 feet or so with the "good" engine throttled right back as it was much easier to keep lined up that way.

I did 'no power' flight in my last sim. (RJ100)

Made a mess of the first one but did a nice landing off the second.

Personally I thought it quite useful. I really had little idea of how far it would go from a given height and was quite surprised at how well it did.

I hope to never use the info for real, but it was only 10 mins in the sim and it probably trebled my chances of a good outcome should I ever run the sucker out of gas! ;).

(heaven forbid :ok:)

Did so many engine out landings that guys have stopped doing them out of boredom.

Having a lots of energy is easy. It's much tougher when you might have just enough energy. Then you have to know your glide speeds and basic gliding/airmanship skills(ground effect can be your friend).

Points well made....seems strange that chopper chaps practice autorotating frequently even when twin or triple engined. On most aircaft, I believe the optimum glide speed is the same as the holding speed at that weight.

quote:
"On most aircraft, I believe the optimum glide speed is the same as the holding speed at that weight."

Not totally wrong but we need to consider best glide angle and minimum rate of descent - not the same thing. Glider pilots know all about this. As a rule of thumb, holding speed +10% wouldn't be a bad speed for glide (clean - no flaps of course).

Jack

The problem I see with practicing engine-out glides is that I'm not sure the sim can simulate TOTAL loss of power. A glide in a jet-powered transport from altitude with the engines at Idle Thrust has to be different than an glide with ZERO trust.

DC-ATE only a marginal difference, but that slight glide path shift wont destroy the laerning value of the exercise--- the real importance are glide line position, ROD and AS control as well as execution of common sense--I not trying to be condescending,... I know you know this all, but you asked:)

Old Smokey
Could I take you up on that one day; I could use the practice? :}

PA

Do you really mean minimum descent rate, or best L-D which gives the greatest glide distance? The two are different. Min Desc (aka min sink) gives the longest time in the air but unless the polar is a rather strange shape, not the longest glide path. The speed for the two is different - min sink is slower.

Well, I doubt my former employer would let me back in the door, but it would be interesting to try gliding to touchdown in "my" old DC-8. I think I'd like to be out in the prairie land though!