Loss of control and ditching.

[4Greens]

The Sioux City accident, in which an aircraft was landed after a complete loss of hydraulics and hence no controls, gave me food for thought.

It ocurred to me that the best option under those circumstances would be to find some smooth water with rescue facilities at hand and to ditch. The advantages being; little or no chance of fire, and lots of runway. I incorporated it into my private checklist.

The recent Hudson river ditching seems to support that theory.
I would be interested to hear other's views.

[Junkflyer]

The Airbus had no thrust, but it still had flight controls; the DC-10 had some thrust, but no flight controls. Not really the same thing. Air Canada (I think) put a 767 glider down on a racetrack and didn't subject anyone on board to the risk of drowning.

[Graybeard]

Thanks might have turned out a little better on UAL 232 had they landed in the soggy cornfield next to the airport. Or maybe worse.

[SNS3Guppy]

UAL232 would have turned out better, but or timing. A rudimentary form of pitch and roll control had been found by using thrust, and a series of descending, turning oscillations performed. that they were able to line up and make the field was a miracle all by itself. They attempted to time the oscillation with the touchdown, and it didn't quite turn out right.

There's nothing they could have done to make that situation better. If you consider all the things that came together in that one place at that one time, it's a beyond-belief miracle. Changing ambulance shifts, changing law enforcement shifts, a medical convention in town, a dental convention across the street...double shift and all kinds of support by *coincidence* happened to be right there, right then.

There's no other way that could have turned out, and no other place it could have happened. A lot of people and a lot of support was brought together and waiting when it happened. Same goes for the crew. All things in their time...but everyone there was in the exact place and time they were supposed to be. Captain Haynes and crew did a miraculous job, given the circumstances, as did every other soul involved.

As for water landings...water isn't simply a nice soft place to land. Judging height above water can be difficult. Water acts hydraulically in many cases to tear aircraft apart. Survival afterward, particularly if the aircraft doesn't remain intact, can be brief, and survival in cold water compounds issues tremendously...as it does relief and rescue efforts.

The crew did a wonderful job in the US Airways mishap, but to suggest that water is usually the best choice would be a very misplaced suggestion indeed. In this particular case, the crew made rapid, good decisions, and executed them very, very well. However, don't use this case to paint others with a broad, one-color brush.

[misd-agin]

UAL 232? Don't take anyone's word for it, read the statements of the actual pilots.

If you're a U.S. based pilot go to the NTSB headquarters in D.C. and read the mircofiche that has the witness interviews on them. That's the data that is edited to present the final report.

No hydraulics for 43+ minutes. Captain and FO still struggling with the flight controls at impact. Hint, it would be the same thing as fighting the controls while parked at the gate and the hydraulic pumps turned off.

The flight crewmember interviews are very interesting. Neither the reports or interviews state who reduced the power after CA Fitch protested the first command to reduce the power - "that's all that's holding your wing up". CA Fitch was correct. Power was reduced and the roll commenced.

[Chuck Ellsworth]

Water as a landing surface for a jet airliner with engines mounted under the wings is a very risky choice.

However in the case of the crew on the airbus they chose the best option available and fortunately all survived.

I was asked what I though about why only one engine separated the from the wings by someone on Avcanada.

I will copy my reply here to give my thoughts on what happened and how difficult it is to know how the landing will turn out.


O.K. as long as everyone here understands that I am only posing a possibility based on what I have observed airplanes to do when landing on the water.

Here is one possibility that seems to me could have caused the left engine to separate and the right one to stay on.

When you look at the engine nacelles from the sides they have a smooth curve upward to the intake lip.

At water contact if the left wing was just a fraction lower that the right wing and the water entered the intake a fraction of a second before the right engine there would be an immediate yaw to the left with the result being a further lowering of that wing.

The right engine nacelle could then momentarily have " skied " just long enough for the deceleration forces to have reduced just enough to not meet the shear point of the bolts as the engine submersed .

There seems to have been a yaw to the left just as it slowed down which could be the result of the left wing having been lower in the water which was first started by the momentary skiing of the right engine nacelle...once the right engine entered the water it would have helped counter the dragging left wing with no engine attached.

There I probably should not have posted that but based on my experience flying sea planes that could be what happened.....

For sure he had the touch down attitude correct because the airplane did not self destruct.

Hopefully you all will take into consideration that is only my take on what could have happened based on my back ground flying and training on large sea planes.

[Luap]

UAL 232 landed with a high speed. And with very little control, one wing would have struck the water first. So a ditching of UAL 232 could have been similar to the ditching of the Ethiopian Airlines 767, in wich most occupants died.

http://aviation-safety.net/database/record.php?id=19961123-0

[4Greens]

The ditching of the Ethiopian airlines was a hijack induced crash, and therefore irrelevant. Let's have some researched thought.

[waren9]

Bit harsh mate.

The effects of the touchdown on water (or land) bear no relevance to how it got to that point in the first place.

I think you've invited (and recieved) some fairly intelligent comment on the merits of ditching in water.

[idleopdes]

My Airbus knowledge is rusty.... what "law" would the US Airways 320 have been in? (engines out, no APU, rat extended, battery power)
I'm wondering about controlability if they were in direct law...

Thanks

[BOAC]

4Greens - I do not know how much 'flying' goes with your 'ATPL', but I need to say 2 things to you:-

1) You owe Luap a forum apology. His post was accurate, relevant and correct

2) If you take no other advice from me, please do NOT try to DITCH an almost uncontrollable a/c full of trusting pax and crew UNLESS there is no choice. Find a nice big airfield where, when you crash as you almost certainly will, rescue services can reach your a/c quickly.

As Luap said, you are most likely to end up digging a wing in or pitching up or down on attempting to touch down, and 180kt plus water is far from soft.

[4Greens]

BOAC- just a lifetime sport; military and civil.

[Rick777]

The A320 in direct law flies just like a regular airplane. Control surface movement is proportional to stick movement. The controls feel kind of sloppy though with only blue hydraulics. You only have one spoiler pair.