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reality of ditching

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Old 2nd Mar 2001, 13:05
  #21 (permalink)  
Old King Coal
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Gotta say that the ditching scene in the Tom Hanks film 'Castaway' is truly superb (even the cockpit drill during the emergency decent, following the explosive decompression, was a fairly good, e.g. O2 on, straight on down to below 10,000' - but if only somebody had remembered to cancel that blasted bell - theatrical license I suppose ?! ). Now having never done a ditching myself, I can't say if this would be truly what it would be like, but I'd hazard a guess that whom ever put this movie clip together had had a good look at the video of the Ethiopian 767 ditching off the Comoros Islands.

My #1 nightmare is having an airborne fire, but after that it's a ditching on a dark and stormy night - and to say that it would not be nice would to understate it ! Eg. You've ditched (crashed) into the sea, maybe at night in, say, only/just a force 4 wind, outside the air temperature is 3C the sea is 10C - even if you manage to survive long enough to get out of the aircraft, do you really think that you'd be able to stay on the wing ? Also you're soaking wet, and likely to be suffering from shock and maybe injured, just how long do you think you'd survive ?! Yeah those nice little safety-card diagrams showing that post-ditching everybody is sitting on the wing…….. Come on, whose kidding who here ?!
 
Old 2nd Mar 2001, 14:12
  #22 (permalink)  
snooky
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I remember BNOC making a safety film in the early 80s which involved landing an S61 on a lake to demonstrate an evacuation. The aircraft was full of aircrew. The first (32 man) raft went upside down, and punctured on an aerial before it could be used. The second, smaller raft was then successfully used to evacuate, but this punctured on arrival at the shore. The boat engine of the craft which was holding the 61 steady then failed, with a risk of grounding the aircraft on the shore, but it eventually took off safely.
This was all on a nice day on a calm lake, a bit different to a winter's night at sea!
 
Old 2nd Mar 2001, 18:43
  #23 (permalink)  
RVR800
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I recall an incident where an engine
failure on a C-172 resulted in a ditching
on the approach to Edinburgh

The crew swam ashore and the human liver for
transplantion was also rescued and transplanted a few hours after

Looks good on the cv? (if its not fuel)

[This message has been edited by RVR800 (edited 02 March 2001).]
 
Old 2nd Mar 2001, 19:22
  #24 (permalink)  
RATBOY
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This topic was addressed about 6 months ago, I think in this forum.

Bottom line is there are rather few ditchings of jet airliners and the reality will likely be rather different than the cartoons in the seatback cards.

The more usual situation for airliners going in the water seems to be overrun. Believe this has happened a few times at LGA, I recall one at Pensacola Fl in the late 70s/early 80s. And then there was Air Florida's spectacular takeoff and aircraft refusal to fly due to ice at DCA.

 
Old 3rd Mar 2001, 00:54
  #25 (permalink)  
SFly
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Arrow

Thanks chaps, knew I could rely on you.

Seriously, I think I'm going to be sick.

 
Old 4th Mar 2001, 05:01
  #26 (permalink)  
Speedbird48
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There was a 707 deliberatly ditched in the Nile South of Khartoum by a Sudan Airways crew.
The airplane was on lease from Air Lingus for the Hadj and was returning from its first trip when the power went off in Khartoum. The Irish crew were still in the Hilton after ferrying it down!!
All got out, only crew on board. The story at the time was that the crew got very low on fuel and with no chance of the lights coming back they found the Nile on the radar and landed in it about 15mls South of town.
I flew over it, it was there for a long time and they recovered the engines as I saw them behind the hangar.
It was said that every mud hut for miles had a triple airline seat with seat belts for a couch!!
 
Old 4th Mar 2001, 09:29
  #27 (permalink)  
Grandad Flyer
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After seeing the pics of the B707 I have thought about ditching procedures. As mentioned, it was a normal approach with gear DOWN and yet it made a landing OK and floated and the fuselage didn't break up. Yet still the manufacturers say gear up for ditching. I reckon that maybe the gear hitting first absorbs some of the initial impact but also keeps the aircraft in a straight line and a little more stable than if one wing touches down first. Gear breaks off, engines break off, fuselage by now probably very little forward movement.
What do others think?

 
Old 4th Mar 2001, 17:32
  #28 (permalink)  
Code Blue
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<font face="Verdana, Arial, Helvetica" size="2">I reckon that maybe the gear hitting first absorbs some of the initial impact but also keeps the aircraft in a straight line and a little more stable than if one wing touches down first. Gear breaks off, engines break off, fuselage by now probably very little forward movement</font>
There is no doubt at all that the slower the cabin & fuselage hit, the less damage will occur to the occupants. You want to slow down as slowly as possible.

I suppose the issue is how controllable the machine is after the gear digs in. If there is a large nose down moment at that time, would the impact of the nose cause the fuselage to break up and how easy is it to hold the nose off. With regard to lateral stability, how easy is it to keep wings level while the pods get pulled off.

------------------
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[email protected]
 
Old 5th Mar 2001, 04:22
  #29 (permalink)  
purple haze
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good point grandad, as SOP say that gear should be up on emergency decent on water, but surely with gear down the fuselage would take less impact, perhaps anyone could comment further?
 
Old 5th Mar 2001, 07:17
  #30 (permalink)  
EI - E I - O
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The bottom line is their built to fly not crash!
 
Old 5th Mar 2001, 22:55
  #31 (permalink)  
Propellerhead
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I heard that the Ethiopian Air ran out of fuel due to draining one of the tanks with fuel still left in the other (forgot about the cross-feed being open maybe?) That's why it dropped the wing. Can't blame him though, as his FO had a fire axe through his head. Not much cross-monitoring going on.

Also heard one about a US C-130 successfully ditching in the sea. The Air Force / Navy decided to run a trial by deliberately ditching another C-130 to study the effects. Unfortunately everyoe died. Don't know if it's true or not.
 
Old 6th Mar 2001, 00:50
  #32 (permalink)  
FasterFaster
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Wink

I spent a lot of time watching TV at BAe Prestwick, waiting for the crosswind to drop below about 600kt so I could do an IR test.

On an episode of Quincy, the great investigative coroner was called upon as an expert witness in an aviation-related case, and testified to the effect that no-one has ever been saved by the liferafts in an airliner.

Quincy said it, that settles it.
 
Old 6th Mar 2001, 09:22
  #33 (permalink)  
Smurfjet
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Re. Ditching with the gears down, if I remeber correctly the 707 Undercarriage, especially the nose gear, don't extend that much from the fuselage, so not sure that they helped in damping the initial impact? Comments?
 
Old 6th Mar 2001, 11:41
  #34 (permalink)  
yowie
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fish

The Ethiopian Capt was fighting off the hijacker just about the time he was trying to flare I beleive,which would have it extremely difficult to get down evenly-not sure of a/c config or if he had hydraulics.Heard most of the pax survived the impact but drowned because they inflated their lifejackets inside the a/c and couldn't get to the exits as it sank.
Also heard of bizjet(falcon/sabre type?)successfully ditching near a major shipping channel(dont know which bit of water)and the local navy having to come and sink it after a few days(weeks?).

------------------
the force,it really sucks
 
Old 9th Mar 2001, 15:06
  #35 (permalink)  
Trash Hauler
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Angry

I have been in many a discussion re ditching. (Fly C130)

The only ditchings that have occurred were either

1. Out of fuel; or
2. In a world of hurt before the ditching.

The bottom line is this. If you are over land you will do anything to put down on a strip. Same for over water keep it going as long as possible. Only when the situation is dire would you consider ditching (or crash landing)

I hope none of you out there or myself for that matter end up in that situation because if things are that bad we probably will not survive.

Cheers
 
Old 9th Mar 2001, 18:53
  #36 (permalink)  
RATBOY
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Re bizjet successsful ditching.

FAA lost a flight check Sabreliner a number of years ago from Acension to Brazil when he ran out of gas. Ditched into the Atlantic near the coast (apparantly found the country but not the airport). Crew of three got out, one died of injuries in the raft, a/c sank like a stone.

Trashhauler has it right, ditching is a last resort and a crapshoot with the odds very in the house's favor.
 
Old 10th Mar 2001, 23:23
  #37 (permalink)  
airforcenone
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RVR800,

The C172 which went into the Firth of Forth was G-GRAY which I had the joy of flying a few days before. Can't remember the exact circumstances but somehow the engine came to bits. The guy who was flying it was an instructor of mine at the time and I think he received an award from GAPAN for his efforts.
 
Old 11th Mar 2001, 01:28
  #38 (permalink)  
Tor
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Red face

If you have a double engine failure on an ETOPS flight over ocean, ditching, to me, seems to be the only resort!

Taking the fact into consideration that every day many ETOPS flights are made over the Atlantic, it's just a question of time before something happens (if not already?).

So it's an interesting subject, "how to ditch perfectly".
 
Old 11th Mar 2001, 13:36
  #39 (permalink)  
dusk2dawn
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"how to ditch perfectly" is described in the AOM/Emergency/Abnormal checklists.
 

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