MADtoCAE From , joined Dec 1969, posts, RR: Posted (7 years 3 months 2 weeks 4 days 19 hours ago) and read 7041 times:
I was looking at my 767 safety cards and I thought:
How long do the people have to get off the plane before it sinks?
What makes it sink slowly?
Looking at those rafts,how many peolple can get on 1 of them?
Thanks in advance
Geoffm From United Kingdom, joined Feb 2004, 2111 posts, RR: 8 Reply 1, posted (7 years 3 months 2 weeks 4 days 17 hours ago) and read 6930 times:
Well, as the hull is pressurised and therefore pretty watertight, and as long as the plane is intact with the open doors above the waterline, then it shouldn't sink. In theory.
It's all to do with the displacement of water vs air. So I guess a fully loaded plane with full wings of fuel might not stay afloat quite so well after all.
Fly2HMO From United States of America, joined Jan 2004, 8123 posts, RR: 9 Reply 2, posted (7 years 3 months 2 weeks 4 days 17 hours ago) and read 6911 times:
I think it would still float with full load/fuel. Jet fuel is lighter than water.
Why if one person has an imaginary friend they're crazy; if many people have the same imaginary friend, its religion?
Nudelhirsch From Germany, joined Oct 2003, 1438 posts, RR: 25 Reply 4, posted (7 years 3 months 2 weeks 4 days 16 hours ago) and read 6885 times:
It is very theoretical, as water landing would in pretty much every case leave serious damage to the airplane, engines ripped off and so on, also if any structural stress has caused sealings to open, if the fuselage is bent (for lack of a better term)...
So I personally would try get out as calmly, smoothly and of course still quickly as I can... Well I guess would stay calm, you never know...
320tech From Turks and Caicos Islands, joined May 2004, 479 posts, RR: 5 Reply 6, posted (7 years 3 months 2 weeks 4 days 13 hours ago) and read 6839 times:
If the outflow valves are open, water will gush in
Not a widebody, but the A320 has a "Ditch Switch" which closes all aircraft openings below the waterline (outflow valve, air cond inlets, avionics vent, etc). I'm sure other aircraft have something similar.
The question, I would think, isn't how long it will float, it's how will the pilots manage to get the thing down intact. An aircraft with podded engines is going to slow down very quickly. That hijacked 767 that ditched several years ago didn't do all that well - though the pilot was interfered with, I understand, so that he couldn't make a good landing. Still . . . not something I'd want to experience first hand.
The primary function of the design engineer is to make things difficult for the manufacturer and impossible for the AME.
SlamClick From United States of America, joined Nov 2003, 10019 posts, RR: 76 Reply 7, posted (7 years 3 months 2 weeks 3 days 22 hours ago) and read 6730 times:
There is just no way you can call that 767 arrival a ditching. A ditching is a controlled landing on water. That was a crash. The plane did not crash because of landing on water. If that plane had been over Muroc Dry Lake it would still have been a crash. It was in at least a 30 degree bank. It was a crash and I don't understand why people keep calling it a ditching. They may have intended to ditch, but they were not given the opportunity.
Happiness is not seeing another trite Ste. Maarten photo all week long.
KYIPpilot From United States of America, joined Oct 2003, 1383 posts, RR: 9 Reply 8, posted (7 years 3 months 2 weeks 3 days 21 hours ago) and read 6711 times:
Gear down greatly increases major damage potential.
I thought when you are ditching you want to leave the gear up. This way the landing will be smoother, as the hull will act like a boat hull. Though most likely the wings will be damaged or ripped off.
"It starts when you're always afraid; You step out of line, the man come and take you away" -Buffalo Springfield
SATL382G From , joined Dec 1969, posts, RR: Reply 9, posted (7 years 3 months 2 weeks 3 days 21 hours ago) and read 6695 times:
For everybody who says a jets going to come apart on ditching. Please post a reference or an example. The only water landing examples I'm aware of (A DC8 at San Francisco, 727 at Pensacola, and the DC9 in the Carribean) suggest the aircraft will be largely intact following the landing. Further neither the DC8 or the 727 was intentionally landed in the water, so I'll presume a crew following procedures would have an even better result.
SlamClick From United States of America, joined Nov 2003, 10019 posts, RR: 76 Reply 11, posted (7 years 3 months 2 weeks 2 days 22 hours ago) and read 6550 times:
MADtoCAE if memory serves the standard size raft in use is 46-man with a 50% overflow capacity. It's been a while. I think Eastern Aero Marine makes them. Perhaps they have a website.
The number of these rafts aboard would then be a function of your aircraft capacity. Seems like they are about five or six meters wide, octagon shaped, with ladders up the outside and some accessories tied to them.
Edit: speling.
[Edited 2004-10-29 17:42:30]
Happiness is not seeing another trite Ste. Maarten photo all week long.
Kiwiineurope From New Zealand, joined Sep 2004, 5 posts, RR: 0 Reply 12, posted (7 years 3 months 2 weeks 2 days 22 hours ago) and read 6544 times:
I thought when you are ditching you want to leave the gear up. This way the landing will be smoother, as the hull will act like a boat hull. Though most likely the wings will be damaged or ripped off.
Yep, sounds right to me, and I think that's what the original poster meant/said - the potential for damage is greater with the gears down, hence gears up is better. At least that's how I read it
Caboclo From United States of America, joined Nov 2004, 203 posts, RR: 0 Reply 13, posted (7 years 2 months 4 weeks 1 day 5 hours ago) and read 6232 times:
SATL382 has a good point. I can't find the pix of that DC-8, but I just re-read the article. It's on this site, titled "The DC-8 That Was Too Young To Die". The Capt had a blond moment, and went into the drink short of the runway. It was a pretty controlled entry, but in landing configuration, ie gear and flaps down, and with 4 podded engines. The article implies it sank pretty quickly, but the gear remained attached and settled on the bottom of the bay before the pax could get their feet wet. I remember seeing pix after they pulled it out, the wings and gear were still attached, don't remember about the engines. In any case, they repaired it and put it back in service.
HAWK21M From India, joined Jan 2001, 29818 posts, RR: 61 Reply 14, posted (7 years 2 months 4 weeks 1 day 5 hours ago) and read 6225 times:
If the outflow valves are open, water will gush in.
Not necessary.The MOV will permit enough water to help close the valve shut by assisting springtension on the Diaphragm.
regds
MEL
242 From United States of America, joined Oct 2000, 498 posts, RR: 1 Reply 16, posted (7 years 2 months 3 weeks 6 days 14 hours ago) and read 6006 times:
>>>Well, as the hull is pressurised and therefore pretty watertight, and as long as the plane is intact with the open doors above the waterline, then it shouldn't sink. In theory.<<<
Reality is different. There are many places for water to enter. Most, if not all airliners have spring loaded fluid drains located along the bottom of the fuselage. These drains close when the cabin is pressurized, and open automaticly when unpressurized. Door seals, window seals, control cable seals (where they pass through bulkheads), wear with aircraft age.
I'd guess a 767 gently placed in a body of water would sink in two hours or less.
Imonti From , joined Dec 1969, posts, RR: Reply 17, posted (7 years 2 months 3 weeks 5 days 19 hours ago) and read 5917 times:
In all fairness planes dont ever land on water, they break up when they hit water.
Look at that 767 off the cost of AUS or some where that was highjacked and ran out of gas. The possibility of the Helderberg hitting water. To hit water at such a speed with such a weight means its overs.
But yeah, would it not sink front first for a 744 as the upper deck is there but then the tail of the 744 would also have to be taken into consideration, it is all a matter of weight distribution.
Wingscrubber From United Kingdom, joined Sep 2001, 775 posts, RR: 0 Reply 18, posted (7 years 2 months 3 weeks 5 days 14 hours ago) and read 5869 times:
Keep this in mind - water is like concrete when you hit it at speed, 1000 times denser than air. It depends on the circumstances but airliners have been known to break up on impact with the waves...on the other hand, others have stayed in one piece. Can't be bothered to quote examples though I'm afraid, am lazy like that.
SATL382G From , joined Dec 1969, posts, RR: Reply 19, posted (7 years 2 months 3 weeks 5 days 11 hours ago) and read 5862 times:
In all fairness planes dont ever land on water, they break up when they hit water.
It depends on the circumstances but airliners have been known to break up on impact with the waves
Sorry gang you can't cite an example where a commercial jetliner broke up during an intentional ditching, because there isn't one. The Ethiopian 767 wrecked because there was a fight going on in the cockpit so that doesn't count.
AFHokie From United States of America, joined May 2004, 221 posts, RR: 1 Reply 20, posted (7 years 2 months 3 weeks 3 days 7 hours ago) and read 5703 times:
Hasn't everyone seen Airport '74??? The movie with the 747 that crashes in the Caribbean and remains intact to sink to the bottom with everyone inside still dry?
Those crazy 70's movies, what was Hollywood thinking?
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