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Videos show US Air crash-landing

cnn.com

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Re: Videos show US Air crash-landing

#11

Post by mhb »

noonespecial wrote: post #8
jayair wrote: post #3

Earlier quoted context omitted.

I'm not a pilot but if you replace the water with the runway you've got what seems like a perfect landing. Any HN'ers with aviation experience care to comment?

Water is much harder. The drag as soon as you touch is incredible so the deceleration is nearly instant. He had to know to keep the gear up, the flaps not extended and touch at the perfect angle. Even then, there is a large element of chance. Most water ditchings end with the plane catching a surface in the water, cartwheeling and then breaking apart. Its hard enough to land planes that are designed with floats on th…

It was an incredible feat, but I don't think that knowing to keep the gear up when landing on water is particularly remarkable.

Re: Videos show US Air crash-landing

#12

Post by jerf »

mhb wrote: post #11
noonespecial wrote: post #8

Earlier quoted context omitted.

Water is much harder. The drag as soon as you touch is incredible so the deceleration is nearly instant. He had to know to keep the gear up, the flaps not extended and touch at the perfect angle. Even then, there is a large element of chance. Most water ditchings end with the plane catching a surface in the water, cartwheeling and then breaking apart. Its hard enough to land planes that are designed with floats on th…

It was an incredible feat, but I don't think that knowing to keep the gear up when landing on water is particularly remarkable.

noonespecial is not talking about landing gear, he's probably talking about things like this: http://www.metacafe.com/watch/48376/plane_crashes_on_water/

Re: Videos show US Air crash-landing

#13

Post by noonespecial »

jerf wrote: post #12
mhb wrote: post #11

Earlier quoted context omitted.

It was an incredible feat, but I don't think that knowing to keep the gear up when landing on water is particularly remarkable.

noonespecial is not talking about landing gear, he's probably talking about things like this: http://www.metacafe.com/watch/48376/plane_crashes_on_water/

Good find. I was actually looking for that to illustrate the fate of most aircraft that attempt to ditch in water.

And yes, I should have been more clear, "gear" would include landing gear (duh), engines, flaps, elevators, or anything else that might "snag" on contact with the water and cause this sort of outcome. The larger the aircraft, the harder it is to prevent this. There is a water landing emergency checklist that usually includes retracting the wheels, pulling in the flaps, etc but the angle and levelness of contact here was all art. Very cool to watch. I'm glad there were some security cameras that caught the actual landing.

Re: Videos show US Air crash-landing

#14

Post by DanielBMarkham »

As a pilot, it's great to watch a guy make something hair-raising into something that looks like a milk run.

I'd be interested to see if the pilot had a float rating. I'd also be curious as to how the wind was in relation to the river. Ideally the plane would be pointing directly upwind as it hit the water.

However the details worked out (and we pilots love the details) the crew had only seconds to configure and land the plane. Kudos to them for being able to change context and execute a fairly rare maneuver without flaw. There are some great stories about commercial jets doing just fine without engines (check out the Gimli Glider for instance http://en.wikipedia.org/wiki/Gimli_Glider) I remember one from South America that involved going through a cloud deck to land on a levee. This pilot gets to add his name to some of the best of the breed. Completely outstanding.

Re: Videos show US Air crash-landing

#16

Post by tlrobinson »

DanielBMarkham wrote: post #14

As a pilot, it's great to watch a guy make something hair-raising into something that looks like a milk run. I'd be interested to see if the pilot had a float rating. I'd also be curious as to how the wind was in relation to the river. Ideally the plane would be pointing directly upwind as it hit the water. However the details worked out (and we pilots love the details) the crew had only seconds to configure and land…

The Gimli Glider incident sounds incredible. I can't imagine how spooky it would be to be in a jet at 40,000 feet and have the engines go silent. How much of the noise in a jet is engine noise vs. air resistance?

Re: Videos show US Air crash-landing

#17

Post by tlb »

That seems like it worked really well. There's been a lot of gnashing of teeth about the fact that jet engines can't survive ingesting birds, but it seems like all you have to do is have a body of water past the end of the runway and a rescue boat ready, and a failed engine is just an inconvenience.

Re: Videos show US Air crash-landing

#18

Post by tlb »

tlrobinson wrote: post #15

Anyone know what they're throwing from the ferry near the end? Life preservers to people in the water, maybe?

I think they're getting rid of the life preservers, because they're bulky and would allow fewer people to squeeze into the boat.

Re: Videos show US Air crash-landing

#20

Post by ars »

vijayshankar wrote: post #7
johnrob wrote: post #5

Very impressive how slow he got the plane to go. Without using the engines for reverse thrust, I don't know how one would slow down.

I think they don't use engines to slow down. I have seen some parts of the wings (like the rear half of the wings..) along its length standing up right ( something like right angle to the direction of motion of plane) putting a lot of resistance to the air while planes need to slow down. Using the engine to slow down is like using the reverse gear of your car to slow down, which no one does, which never works (becaus…

They have three things:

Those surfaces as you call them. Thrust reversers (basically fins that push over the end of the jet and redirect the thrust forward), and the brakes on the wheels.

All planes must (by FAA regs), be able to land without using the thrust reversers (using the brakes instead), but thrust reversers are what's used in normal cases (since it saves wear on the brakes).

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