Is it possible to fly a 747-400 using throttles alone?

[Bruce (a.k.a. brian747) 142]

Astonishingly, the answer is evidently yes.

 

The video, which shows a go-around and a landing, is produced by Hardy Heinlin, the one-man author of the Precision Simulator X destop model of various marques of 747-400, who has spent countless hours in 744 simulators and probably knows more about the systems of the 744 than many pilots. (Certainly, none of the RW 744 Captains on the Aerowinx forum have debated this topic with him, other than asking why he chose to use Alt flaps).   

 

As he says on YouTube: "All hydraulic systems are depressurized, that is, all flight controls are inoperative. But the aircraft is so stable that the flight path can be maintained by thrust modulation and asymmetrical throttle settings."

 

View the video, it's most impressive!. (I recommend opting to view it in 1080p, rather than the default). And having tried it in PSX myself, believe me it isn't nearly as easy as Hardy makes it look! (Actually, it's very difficult — I'll keep trying, though... Maybe I'll make it eventually).   

 

For the thread on the Aerowinx forum, see here —

 

http://aerowinx.com/forum/topic.php?id=2877

 

For the video only, see here —

 

https://www.youtube.com/watch?v=jN9lpXG0o_k&feature=youtu.be

 

It's a masterly demonstration (as well as being a demonstration of how PSX can flexibly present the various elements of a 744 cockpit on a single screen), as well as being a useful learning exercise.

 

 

Cheers,

 

bruce

a.k.a. brian747

 

 

[MartinW 0]

Oh yes indeed.

There was the DC-10 crash some years ago, where I believe this was first demonstrated. Sioux City Gateway Airport I recall. They had almost no control and had to turn with asymmetric thrust. Up and down by increasing and decreasing power. I recall lives were lost, but many saved.

There was also an incident more recently, over Iraq I recall. An Airbus, shot at by an air to ground missile. Same scenario, had to control the aircraft with just power. That one landed successfully with no lives lost.

In fact after the Sioux City Incident, NASA developed a system to automate the procedure. So that pilots flicked a switch and power was controlled with the yoke. Great system, but it was never introduced by the airlines due to cost, and the fact that it would very rearely be utilised.

[mutley 4,497]

Very impressive, he nearly got it the first time around 

[Bruce (a.k.a. brian747) 142]

@MartinW

I wish I still had a memory like yours (yesterday is already fairly fuzzy, for me), so thank you for the references.

The Aerowinx thread I linked above also gives this link concerning United Airlines Flight 232 from Denver, Colorado, to O'Hare International Airport in Chicago in 1989:

 

http://en.m.wikipedia.org/wiki/United_Airlines_Flight_232

Interesting, albeit somewhat harrowing, reading.

 

 

@Joe

 

Y'see, I must have somehow missed all this, I had never heard of controlling an airliner using the throttles alone, so please excuse my ignorance.   

> "...he nearly got it the first time around"

 

<grin> Well being the benevolent old buffer that I am, I preferred to suppose that he had set out to demonstrate a go-around.  

But hey — "Any landing you can walk away from...", as the saying goes. (Let alone avoid completely, by doing a go-around).  

(Also, wait until you've tried it yourself, Joe — the first couple of times that I tried it I found it to be a seriously eerie experience. Very odd indeed).      And as Hardy says in the thread: "If you are a new pilot and you're having difficulties maintaining altitudes and glidepaths by the elevator, i.e. if you're applying large and many elevator inputs, then you're probably flying the aircraft 'by the scenery' rather than by the attitude indicator."

 

I guess it's another example of the difference between professional and simulator pilots: the pros train for *everything*, whereas most simmers imagine that they have the experience of 1,000 flights — when in fact most have the experience of one flight 1,000 times over.   

 

<Hold one, while I prepare my flame-proof shelter...>

 

Incidentally, I'm not sure whether that scenario can be properly simulated on anything other than PSX — I assume Hardy pulled the relevant Circuit Breakers to depressurise all the hydraulics. (PSX simulates them all).

 

 

Cheers,

 

B.
 

[allardjd 1,853]

I believe a Japanese 747 that suffered a rear pressure bulkhead failure and loss of most of its rudder flew for about an hour with marginal control using mainly the engines before impacting a mountaintop. The accident took place in Japan and I think there was only one survivor, a young girl in the rear of the cabin. It didn't end well but they did manage to remain airborne for some considerable time before hitting terrain.

 

I think that one may have even pre-dated the Sioux City crash.

 

John

[Bruce (a.k.a. brian747) 142]

Thank you, John. 

 

<sigh>  Too many accidents. (OK, one is too many...).

 

On a lighter note, I once heard an after-dinner speech about aviation in which, when it came to safety, the speaker suggested that you should always sit near the back — "...because they never knowingly reverse into hills".

 

He then got a bit silly and added that "...for ultra-safety you should try and find out which seat the black box recorder is under, and sit there. If that's the only bit they expect to get back, then you need to be fastened to it!".

 

Sometimes humour is the only prophylactic against potential horrors....  

 

Cheers,

 

B.

 

[ddavid 149]

I guess you guys have seen this film?

http://www.youtube.com/watch?v=-xzkVP8oJV4&feature=youtube_gdata_player

Not Kiefer Sutherland's best, but interesting for the thrust only directional control point of view.

Cheers - dai.

[dodgy-alan 1,587]

The Souix City crash was bought on by the rear engine exploding and debris smashing all 3 elevator control links if I recall correctly. There are was a documentary about it called The Unflyable Plane. It made aircraft manufacturers to look very carefully at control routing in new aircraft.

 

[allardjd 1,853]

...the rear engine exploding and debris smashing all 3 elevator control links...

 

 

If I recall correctly it took out all three hydraulic systems too.

 

John

[MartinW 0]

And luckily for them, a very experienced DC-10 pilot was a passenger. While the pilots applied considerable force on the yokes in order to maintain control, he handled the thrust levers.

On approach, he realised the vertical speed was way too high, so at the last minute appled thust. His actions were responsible for saving many lives.

[hifly 925]

There was also the 'Windsor Incident' AA flight 96. decompression due to the cargo door failure. (This was before the Turkish DC 10 Paris disaster). Loss of #2 engine, partial loss of hydraulics, rudder jammed to max one way or another. Pilot used ailerons and thrust to maintain control. Landed safely at Detroit. By coincidence he had practiced for a loss of hydraulics in a sim only weeks before. 

[hurricanemk1c 195]

JAL 123 was August 12 1985, whilst UAL 232 (Sioux City) was July 19, 1989

 

It can be done, just quite tough to do so!

[allardjd 1,853]

I'd have to say you can probably fly it, but landing it might be quite another matter.

 

John

[britfrog 180]

I have demonstrated to a friend that it is possible to take off and land without touching the control column (albeit in a c150) at Popham but I did have to use the elevator trim and rudder pedals .

when I learnt to fly my instructor at the time kept spanking my hands when they were on the column saying that is for propping your newspaper against or for stopping your sandwiches from falling off your lap.

Of course his aim was to make sure you knew what a rudder was for , and it came very handy in later life when flying big singles ,

[MartinW 0]

I'd have to say you can probably fly it, but landing it might be quite another matter.

John

Indeed very tricky. But it has been done...

 

On 22 November 2003, shortly after takeoff from Baghdad, Iraq, an Airbus A300B4-200F cargo plane owned by European Air Transport (doing business as DHL Express) was struck on the left wing tip by a surface-to-air missile. Severe wing damage resulted in a fire and complete loss of hydraulic flight control systems. Because outboard left wing fuel tank 1A was full at takeoff, there was no fuel-air vapour explosion. Liquid jet fuel dropped away as 1A disintegrated. Inboard fuel tank 1 was pierced and leaking.[1]

Returning to Baghdad, the three-man crew made an injury-free landing of the crippled aircraft, using differential engine thrust as the only pilot input. This is despite major damage to a wing, total loss of hydraulic control, a faster than safe landing speed and a ground path which veered off the runway surface and onto unprepared ground.[2]

http://en.wikipedia.org/wiki/2003_Baghdad_DHL_attempted_shootdown_incident

Wiki article. Flight With Disabled Controls...

http://en.wikipedia.org/wiki/Flight_with_disabled_controls