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Question About Sea ditching

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Hi guys, Well ive been thinking about this for while, so can anyone of you help me out? Say if i was returning back from Manchester UK to Newark US, in a COA 752. I was over the atlantic, and suddenly both engines started surging then completley fired out. When we got to a lower altitude it was clear now we would have to ditch. When we got lower about 1000-2500ft we could see the waves were blowing East and it looked very choppy. Right... Would we land into the Waves on a westerly heading, or land in the direction of what the waves were blowing in (in this case East). Or would it be the opposite, to try and land on a Northernly, or Southernly heading, across the waves? Cheers, Tom

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Hi guys, Well ive been thinking about this for while, so can anyone of you help me out? Say if i was returning back from Manchester UK to Newark US, in a COA 752. I was over the atlantic, and suddenly both engines started surging then completley fired out. When we got to a lower altitude it was clear now we would have to ditch. When we got lower about 1000-2500ft we could see the waves were blowing East and it looked very choppy. Right... Would we land into the Waves on a westerly heading, or land in the direction of what the waves were blowing in (in this case East). Or would it be the opposite, to try and land on a Northernly, or Southernly heading, across the waves? Cheers, Tom
Generally you try and land in the trough, across the wind... on the other hand, I'm not aware of anyone ever successfully ditching a modern jetliner - or even trying to do so. DJ

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Has Sully been forgotten already?

... on the other hand, I'm not aware of anyone ever successfully ditching a modern jetliner - or even trying to do so. DJ
Have we forgotten about Sully already?

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Has Sully been forgotten already? Have we forgotten about Sully already?
Sully hasn't been forgotten, but he didn't attempt a ditching at sea... DJ

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Having done this for real in the English Channel in the early eighties!! If you have the luxury of being able to see the wind direction and being able to turn into wind of course that will help. Do not as has been said earlier land in the trough of the swell. Your a/c will be immediately swamped. You must land along the crest of the swell however choppy the sea maybe and whatever the wind direction is at that point. You must select the correct flap setting according to the manual and monitor your airspeed and attitude with precision.Make sure your Mayday call is fully understood with an accurate position report, heading, SOB etc.I had a fatigue failure in my propeller. I turned back to the UK making my mayday call opened the doors getting everything ready for evacuation. All five of us got out, inflated our life jackets, and got into the dinghy. Very soon after the a/c went under but at the same moment the helicopter was arriving overhead. Not an experience I would like to repeat in a rough sea. It was force 4 if I remember correctly.Never done it in an airliner fortunately!! I think it would break up.vololiberista


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For large aircraft, the conventional wisdom is to land into the wind only if the sea is relatively calm (swells with no cresting waves), and to land parallel to the wave crests (crosswind) if seas are high enough for them to exist. The thought is that direct impact with a wave during the landing could break up the fuselage. So in the scenario presented, a N/S heading would be used.


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Hello everyone.Based on your definition / description == choppy - rough with small waves; "choppy seas", and knowing the wind direction, I recommend landing Into the wind. The most damage gets done during the initial impact, which means that the longer and slower / softer you can touch down, the most likely you are to survive. There are other factors you must take into consideration, configuration, loading etc. to get a better chance but the basics are:Small waves / choppy == into the wind /into the wave.Large waves, I look for the white crest feedback == along the waves, if sufficient control, on crest, right behind the white water. The best thing is to fly at an altitude that you can glide to some solid surface, or close to a ship etc., kind hard to do on a trans oceanic flight, but very possible in most other flights, but most pilots still do not follow that rule. TV

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A few things you would/should do if you had to ditch an airliner: The moment that you think ditching is a potential scenario, you transmit a mayday/pan on the normal frequency plus selcal/acars. If that is not received, or you are not certain it has been received, then repeat on 121.5 Mhz, 2182 KC, or 8364 KC (HF) and go to 7700 on the transponder. The info you send should include position, course, speed and altitude, as well as the situation, your intent, and the aircraft type. Ditching is always done at the lowest weight possible, typically fuel is dumped to just above auto shut off levels just prior to ditching and you should then close the dump valves. Even if it were possible (say on a C-130 or similar) cargo is rarely dumped as it aids structural integrity during an impact and can assist buoyancy. You should depressurise, close the ram air intakes, and any cooling air intakes as these will all allow water ingress. Ditching is done typically with full flaps and a descent speed of 2-300 fpm. You ditch along (parallel) to the swell, and this means there will likely be a crosswind, so you should be aware of that. One visual difference that is important here, is to keep the wings parallel with the surface and not the horizon, as that would be deceptive and nose you under, when contact looks to be soon, you go to ten degrees nose up, and to achieve that you should have dived a bit to ensure that you would be able to hold that attitude at the time of touchdown with full flaps. If done correctly, the deceleration force for the average jet airliner will be 3-5G as the aircraft makes full contact with the water and it will typically cover about 200 yards before it stops completely. It is advisable to consider landing into the wind regardless of swell if the surface wind is estimated to be over 35 knots, since high wind speeds combined with missing the crest of the swell risks a cartwheel if a wing drops a lot. You would be able to determine wind speed from the presence of white crests whipping off the waves, which is a phenomenon that typically occurs at about 45 knots or so. At 2,500 feet above the water before touchdown, the announcement to the cabin should be ''attention, take position for water landing in two minutes'', at 500 feet warn the crew, at 50 feet issue the ''brace for impact'' announcement. You should dress in all the warm clothes you have, but remove your tie and shoes (the cabin crew would tell passengers to do the same, since shoes can damage rafts and ties can snag stuff and throttle you). Cabin crew would also move all loose stuff in the cabin to the toilet compartments to prevent it flying around under impact. You should also note that many aircraft would float slightly tail down as the engines would very likely be torn off, making the aircraft tail heavy, so opening the rear exit door may have to be avoided unless there is no choice, but in most cases the overwing exits would be the best choice as this is where the rafts can launch from and the wings aid a speedy egress on water, plus the empty wing tanks will maintain buoyancy. The inflatable door slides on most airliners are not certified as rafts, but they can be used as such. All the rafts would be tied together so that they make a bigger target for a visual search and are less likely to be tossed around by waves when that way as well. Fortunately, this is all an incredibly unlikely scenario, for example, the most popular airliner in the world - the 737 - has never made an open water ditching (and 737s do make some overwater flights, including transatlantic ones), there are only two instances of 737s ever coming down in water for a ditching, one in a swamp just after take off (everyone survived) and one in a muddy shallow river (one cabin crew member was killed when the tail broke away). Most info in the pilot operating manuals for ditching an aircraft type is based on data gained from floating large models in water tanks. Al


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Generally you try and land in the trough, across the wind... on the other hand, I'm not aware of anyone ever successfully ditching a modern jetliner - or even trying to do so.
The closest example of this would be Ethiopian Airlines Flight 961, a 767-260ER that ditched off the coast of Africa:
Far from successful but you can see him trying to get it in-between the troughs like you said, but the cross wind was a bit much and the wingtip made contact first. Looks like it broke up when the left engine hit the water: Ditching_of_Ethiopian_Airlines_Flt_961.JPG 50 people survived that landing so not bad all things considered, Cheers

Matthew Kane

 

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To be completely fair, the pilot of Ethiopian Airlines Flight 961 - Captain Leul Abate - was being attacked by a hijacker at the time he was trying to ditch, which makes that a remarkably good attempt under the circumstances. In truly modest fashion however, Abate is on record as saying that his co-pilot - Yonas Mekuria - is the real hero of the incident. Mekuria, who had been attacked with an axe, fought off the hijackers to enable Abate to attempt that ditching. The wingtip hit the water because one of the hijackers grabbed the controls, otherwise it probably would have been a flawless ditching (he was orignally trying to dead-stick it into FMCH, but the fight in the cockpit forced him to ditch it at 175 knots instead). Abate is a remarkable, calm and experienced pilot, who can certainly cope with pressure because he has in fact been hijacked three times - twice before this incident - and on those occasions he resolved the situation peacefully and landed the aircraft safely, and he would have done it three out of three times if that asshat hijacker hadn't grabbed the wheel and put a wing low. Al


Alan Bradbury

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To be completely fair, the pilot of Ethiopian Airlines Flight 961 - Captain Leul Abate - was being attacked by a hijacker at the time he was trying to ditch, which makes that a remarkably good attempt under the circumstances. In truly modest fashion however, Abate is on record as saying that his co-pilot - Yonas Mekuria - is the real hero of the incident. Mekuria, who had been attacked with an axe, fought off the hijackers to enable Abate to attempt that ditching. The wingtip hit the water because one of the hijackers grabbed the controls, otherwise it probably would have been a flawless ditching (he was orignally trying to dead-stick it into FMCH, but the fight in the cockpit forced him to ditch it at 175 knots instead). Abate is a remarkable, calm and experienced pilot, who can certainly cope with pressure because he has in fact been hijacked three times - twice before this incident - and on those occasions he resolved the situation peacefully and landed the aircraft safely, and he would have done it three out of three times if that asshat hijacker hadn't grabbed the wheel and put a wing low. Al
+1, I watched this on aircrash investigations and that pilot did the best he could under the situation

Chris Howard
 

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