Ditching?
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Flock1
On a PA28, I would definitely unlatch the top latch before the touchdown. (I think all PA28s have TWO door locks on the single door).
As for time to sink, what I've read suggests several minutes for a low-wing plane
On a PA28, I would definitely unlatch the top latch before the touchdown. (I think all PA28s have TWO door locks on the single door).
As for time to sink, what I've read suggests several minutes for a low-wing plane
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Suppose it depends how much fuel you have onboard and how much damage you do in the process of ditching. Full tanks, with no leaks might lead to the aircraft partially submerging, but remaining afloat as fuel is lighter than water. Never done it so I can't really speak from experience.
Could always get an "air pocket" to go between the chambers of your life jacket if you're worried about not getting out. A small pouch which attaches to the life jacket, and in an energency, you rip the velcro, and pull out a mouthpiece and nose clip. Before you go under, you pull out the mouthpiece and inflate the bag (which also has a small air cylinder activated by hydrostatic pressure), and you can get up to five minutes of breathing under water. Used to carry them on North Sea helicopters, and they work really well (though never had to use it in Anger
)
EA
Could always get an "air pocket" to go between the chambers of your life jacket if you're worried about not getting out. A small pouch which attaches to the life jacket, and in an energency, you rip the velcro, and pull out a mouthpiece and nose clip. Before you go under, you pull out the mouthpiece and inflate the bag (which also has a small air cylinder activated by hydrostatic pressure), and you can get up to five minutes of breathing under water. Used to carry them on North Sea helicopters, and they work really well (though never had to use it in Anger
)EA
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englishal
I am not sure either would work.
Is there a plane whose empty tank volume is enough to float it? (i.e. empty tank volume in litres exceeds the empty weight in kg) That would be pretty amazing. I am sure every light plane will sink quickly, no matter what it is in the tanks.
On the other one, do you mean being able to breathe when the plane is submerged? If so, isn't that assuming a certain max water depth?
I am not sure either would work.
Is there a plane whose empty tank volume is enough to float it? (i.e. empty tank volume in litres exceeds the empty weight in kg) That would be pretty amazing. I am sure every light plane will sink quickly, no matter what it is in the tanks.
On the other one, do you mean being able to breathe when the plane is submerged? If so, isn't that assuming a certain max water depth?
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Have a look at these links
http://www.avweb.com/news/safety/182976-1.html
http://www.avweb.com/news/safety/183010-1.html
http://www.avweb.com/news/safety/182976-1.html
http://www.avweb.com/news/safety/183010-1.html
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Good point on the fuel tank weight. If 200l is the tank size, a maximum bouyancy of 200Kg could be expected I suppose......not much. Full fuel (if a s.g of 0.75) and you'd only have 50Kg of buoyancy.
The airpockets do work, and work well. I guess they wouldn't work very deep, though they work well at the bottom of a swimming pool As you initially breath out into the mouthpiece, it inflates an airbag which as you get deeper is pressurized by the water, so its not like using a snorkel. Plus the extra charge of air from a small (30g?) cannister gives you a bit more than a lungs volume in the bag, which is easily re-breathed for several minutes.
And they wouldn't impede an exit from a submerged aircraft, which is why the likes of Shell use them on their helos....
Cyer
EA
The airpockets do work, and work well. I guess they wouldn't work very deep, though they work well at the bottom of a swimming pool
As you initially breath out into the mouthpiece, it inflates an airbag which as you get deeper is pressurized by the water, so its not like using a snorkel. Plus the extra charge of air from a small (30g?) cannister gives you a bit more than a lungs volume in the bag, which is easily re-breathed for several minutes.And they wouldn't impede an exit from a submerged aircraft, which is why the likes of Shell use them on their helos....
Cyer
EA
Jodels float quite well being wood and all. A chap ditched off the Isle of Man a few years ago and the SAR bods found him sitting on his upturned aeroplane.
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englishal
I think that the instant the aircraft is fully submerged, it will sink very rapidly (at several kt at least, and nose-down) all the way to the bottom. This is what happens with ships; I've seen a few documentaries on it (back when BBC2 used to have "intelligent" material
)
So the objective must be to get out before that happens, unless one is sure of the depth. And even then, let's say the water is 40m deep, you have very little time down there before you can escape; I've done the BSAC scuba course and it is only a few mins before you get the bends after a straight ascent. IOW, I would be amazed to hear of anybody escaping after a plane has fully submerged, but it's possible.
The first of the two links posted by owenlars suggest that one can get out when submerged but that appears to be based on pool experiments. If escaping from a Cessna, one might well have to escape from a water-filled cockpit but one still needs to get out before the wings go under; after that it will sink rapidly. In the 2nd one, the pics of the ditched Cessna were taken shortly after it touched down, judging from the white area of the water. I bet they got out very quick.
LowNSlow
Would a Jodel float with the engine still attached, if full of water?
I suppose there is no reason why a plane's wings could not be foam-filled. It could make it buyoant, at the expense of not being able to inspect the spar
I think that the instant the aircraft is fully submerged, it will sink very rapidly (at several kt at least, and nose-down) all the way to the bottom. This is what happens with ships; I've seen a few documentaries on it (back when BBC2 used to have "intelligent" material
) So the objective must be to get out before that happens, unless one is sure of the depth. And even then, let's say the water is 40m deep, you have very little time down there before you can escape; I've done the BSAC scuba course and it is only a few mins before you get the bends after a straight ascent. IOW, I would be amazed to hear of anybody escaping after a plane has fully submerged, but it's possible.
The first of the two links posted by owenlars suggest that one can get out when submerged but that appears to be based on pool experiments. If escaping from a Cessna, one might well have to escape from a water-filled cockpit but one still needs to get out before the wings go under; after that it will sink rapidly. In the 2nd one, the pics of the ditched Cessna were taken shortly after it touched down, judging from the white area of the water. I bet they got out very quick.
LowNSlow
Would a Jodel float with the engine still attached, if full of water?
I suppose there is no reason why a plane's wings could not be foam-filled. It could make it buyoant, at the expense of not being able to inspect the spar
IO540 the one in the picture did! It had flipped onto it's back upon hitting the water. I'd imagine this would have trapped a lot of air in the fuselage plus the wings are virtually air sacks. The Conti O-200 in the nose isn't all that heavy compared to some engines either
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Would anyone be interested in a ditching course???
We ran one a few years ago, in the sea, of the Donegal cost,
Had great help from, Irish Air Corps, RNLI, Coast Guard, & Local diving club.
Very real & very cold,
Tony
We ran one a few years ago, in the sea, of the Donegal cost,
Had great help from, Irish Air Corps, RNLI, Coast Guard, & Local diving club.
Very real & very cold,
Tony
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I read an accident report a few years back where a double engine failure (caused by fully closing the wastegates of a naff RayJay turbo system and briefly attaining stratospheric power before jettisoning the molten cylinders down the exhaust pipes) ended in a frozen lake and sinking. The engineer - who was along for the ride - kicked the co-pilot's window clean out and they were able to escape. All the more amazing was the fact that this was a pressurized twin (might've been an old 340) with seriously beefy windows.
The body is capable of some amazing stuff when under duress dontchathink?
I'd have thought that some kind of pointed escape hammer would be useful for such an event.
The body is capable of some amazing stuff when under duress dontchathink?
I'd have thought that some kind of pointed escape hammer would be useful for such an event.
Having done the North Sea survival course (many moons ago) I would recommend it to anybody who thinks they don't need a survival suit in our (UK) coastal waters. The level of disorientation experienced when you go upside down and submerged has to be experienced to be believed. The cold that seeps into your bones very quickly (summer or winter) that dulls your reactions and thinking also has to be experienced to appreciate how quickly you are reduced to an automaton.
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Good point. Assuming you survive the ditching (and statistics show that most ditchings are sucessful according to the NTSB), thats when your problems start.
I watched a video on a North Sea survival course of Duncan Goodhew and Sharon whatshername (Olympic swimmers) dumpped in a swimming pool at average UK water temps, and after 10 minutes they were both useless, and they are sh*t hot swimmers.I can vouch that the costal waters are still bloody cold, even in a 5mm wetsuit, the Channel Light Vessel is showing 10°C at the moment. There are some interesting graphs around showing survival time vs water temp, and its not very long at these temps.
EA
I watched a video on a North Sea survival course of Duncan Goodhew and Sharon whatshername (Olympic swimmers) dumpped in a swimming pool at average UK water temps, and after 10 minutes they were both useless, and they are sh*t hot swimmers.I can vouch that the costal waters are still bloody cold, even in a 5mm wetsuit, the Channel Light Vessel is showing 10°C at the moment. There are some interesting graphs around showing survival time vs water temp, and its not very long at these temps.
EA
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I am sure that without either a raft or a drysuit (or a wetsuit, but one isn't likely to be flying with one of those ) one would not survive for longer than an hour or two around here.
But... if you are in the water without a raft, how will they find you in a sea state other than calm, other than pure luck? Only your head/shoulders will stick out.
Unless I am missing something, I think a raft is very necessary.
Obviously one could get lucky and be seen by a boat or such.
Re the ditching course: I could be very wrong on this but I think the purpose of these "North Sea oil platform worker" ditching courses is to get out of a ditched helicopter which is upside down, but will not sink because it has floats; it just won't stay upright if the sea is too rough.
I am very sure that by the time a plane's cockpit is really filled with water (which for a non-pressurised aircraft means most of the water came in via the engine compartment and via the tail section which must also be full of water) the whole thing will sink rapidly to the bottom.
So one must get out very quickly. I am not suggesting a ditching course would be a waste of time; anything that brings people into rapid contact with cold water is worth doing - just that it isn't going to be representative of any survivable situation.
) one would not survive for longer than an hour or two around here.But... if you are in the water without a raft, how will they find you in a sea state other than calm, other than pure luck? Only your head/shoulders will stick out.
Unless I am missing something, I think a raft is very necessary.
Obviously one could get lucky and be seen by a boat or such.
Re the ditching course: I could be very wrong on this but I think the purpose of these "North Sea oil platform worker" ditching courses is to get out of a ditched helicopter which is upside down, but will not sink because it has floats; it just won't stay upright if the sea is too rough.
I am very sure that by the time a plane's cockpit is really filled with water (which for a non-pressurised aircraft means most of the water came in via the engine compartment and via the tail section which must also be full of water) the whole thing will sink rapidly to the bottom.
So one must get out very quickly. I am not suggesting a ditching course would be a waste of time; anything that brings people into rapid contact with cold water is worth doing - just that it isn't going to be representative of any survivable situation.
Having had the dubious pleasure of being "dunkered" every couple of years, plus wet winched at the same sort of periodicity, I can vouch for the fact that there is no substitute for doing it in the cold sea. I did dinghy drills every 6 months (IIRC) in a swimming pool, and it was far from realistic, in fact it often turned into a bit of a laugh.
One SurvO decided to make sea drills a bit more realistic, by dropping us about 5 or 6 miles offshore and leaving us alone for a while. All went well until the SAR diver did his usual dirty trick of turning the one man life rafts over unexpectedly, dumping us all back into the sea one by one. It was April, and the sea temp was around 9 deg C.
One of my colleagues had the misfortune to have the CO2 bottle pulled off his raft, causing it to deflate. He struggled for about 5 minutes or so to board the soggy mass (they stay afloat from the floor and canopy inflation) before giving up. Two of us paddled over to help him out, only to find that he appeared to be drunk, was giggling and couldn't care less whether he got into the raft or not. We sorted him out as best we could and pinged off a miniflare to call in the helo, as the guy was clearly hypothermic.
Bear in mind that we were all dressed for the occasion, with thick underwear, wooly bear, immersion suit flying gloves and helmet and this chap had only been in the water for ten minutes tops.
Those flying over UK waters in shirtsleeves really don't stand much of a chance of being able to help themselves I think. Certainly I always wear a survival suit, even for relatively short water crossings.
One SurvO decided to make sea drills a bit more realistic, by dropping us about 5 or 6 miles offshore and leaving us alone for a while. All went well until the SAR diver did his usual dirty trick of turning the one man life rafts over unexpectedly, dumping us all back into the sea one by one. It was April, and the sea temp was around 9 deg C.
One of my colleagues had the misfortune to have the CO2 bottle pulled off his raft, causing it to deflate. He struggled for about 5 minutes or so to board the soggy mass (they stay afloat from the floor and canopy inflation) before giving up. Two of us paddled over to help him out, only to find that he appeared to be drunk, was giggling and couldn't care less whether he got into the raft or not. We sorted him out as best we could and pinged off a miniflare to call in the helo, as the guy was clearly hypothermic.
Bear in mind that we were all dressed for the occasion, with thick underwear, wooly bear, immersion suit flying gloves and helmet and this chap had only been in the water for ten minutes tops.
Those flying over UK waters in shirtsleeves really don't stand much of a chance of being able to help themselves I think. Certainly I always wear a survival suit, even for relatively short water crossings.
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But... if you are in the water without a raft, how will they find you in a sea state other than calm, other than pure luck? Only your head/shoulders will stick out.
QDM
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QDM
If you have a 400MHz EPIRB with you, definitely, and everybody should have one. But at £600-£1000, very few people going cross-channel will though. I have one in my emergency bag and would hope to grab that on the way out. But if you only just managed to escape in your drysuit, the chances are that you didn't manage to retrieve it...
Timothy
Presumably if it was badly damaged then it would? Otherwise, how did the water get in?
If you have a 400MHz EPIRB with you, definitely, and everybody should have one. But at £600-£1000, very few people going cross-channel will though. I have one in my emergency bag and would hope to grab that on the way out. But if you only just managed to escape in your drysuit, the chances are that you didn't manage to retrieve it...
Timothy
Presumably if it was badly damaged then it would? Otherwise, how did the water get in?
The water gets in because the winscreen shatters when the nosewheel (mainwheels in a taildragger) drags the nose down and the thin perspex windscreen isn't designed to resist water hitting it at 40+mph so it fails.
I've been told that most taildraggers flip over on ditching whereas trikes tend to plough in as the drag of the wheel is better spread along the heavy end of the aeroplane. Anybody got any examples to back up / disprove this?
I've been told that most taildraggers flip over on ditching whereas trikes tend to plough in as the drag of the wheel is better spread along the heavy end of the aeroplane. Anybody got any examples to back up / disprove this?