Hi there,
Take for example, N862/A25 from BHD to DIN in a SEP. It’s a reasonable span over water, in particular with a headwind it can seem to take a while. I’m not totally comfortable with the overwater flights, in particular when cooler water temperatures or rescue weather less than ideal – as there is little point in having warm water and 100’ overcast. Has anyone worked out a way of determining the actual risk of such legs or reasonable personal minima for such? It’s a bit limiting not to fly over water.
DMEarc
Always carry what you want to have with you if you ditched, and if the water is cold, wear it! I always have inflatable life jackets aboard for summer flying, and am wearing a full dry immersion suit for cold water overflights. When flying a city shoreline, I would often choose a shore forced landing in the water, rather that impact something in a built up area. I have no right to imperil someone else on the ground over my own risk. If this will be frequent, consider taking an underwater egress course. You will either find it a fascinating experience, or decide that you just should not fly over water!
The engine does not know what it is flying over!
What’s wrong with the old “the aircraft doesn’t know it’s over water”-argument? ;)
I think there as many answers to this as there are pilots. I do fly fairly long stretches over water on occasions, if the water temperature is surviveable for a while.
I agree with Fly310. I occasionally fly out of gliding distance from land and although the risk is greater, my total risk exposure increases only marginally.
An emergency landing in pine forest is no fun either. I’d take a lake any day.
I think one interesting point, that I have never really heard mentioned is that it is far safer flying a faster aircraft over water.
Take 180kts vs 120kts, given one leg will have a 30kt headwind (always seems the way?), we have 150kts vs 90kts – reducing the exposure time (risk of water landing) by approx 40%. If we dug deeper into this, we’d likely see the exposure time is the portion outside of the gliding distance from shore – so on a 60nm crossing, we can assume non-oxygen gliding distance of 8nm*2 and an exposure gap of 44nm. Using the above, we’d see an exposure time of 29min vs 17min.
It would be interesting to do a proper EASA risk analysis on this, but first we need to know the probability of a well maintained certified piston engine suffering such a catastrophic mechanical failure as to make further powered flight impossible.
@Peter has said that the probability is small and I’m sure he is right, but I’m struggling to put a figure to it. I’ve seen probabilities as high as one in 10,000 hours quoted for Lycoming engines, but I think that may include readily-preventable and non-catastrophic failures. Is it too much to hope that excluding these would result in a figure closer to 1/100,000?
Whatever the stats. it is very remote – of course until it happens to you.
and only you can set your risk profile.
If you cant get high enough to glide to one side or the other, then I know it is stating the obvious, but ditching is the only answer.
If you want to mitigate risk you understand that in the winter through to very late Spring your life expectancy in the water is very short and you are very unlikely to survive unless you are able to get into a raft with canopy. Interestingly the water is colder late winter well into Spring than the Autumn early winter.
Sea state will have a signifcant effect on how successful you are able to ditch.
To stand a chance of rescue the coastguard being able to pinpoint your position is vital. The aircraft will almost certainly sink and even if it doesnt will drift differently from you, hopefully in a raft.
As a pilot, but as a sailor often sailing in the winter I think about this more than most and have listened and watch to many rescues over the radio or when they have been close by.
As ever if you do ditch in the winter / eary spring it is only with careful planning that you are likely to survive, but then it will almost never happen.
Obviously the probability of a catastrophic engine failure is very small, but the probability of other things which can stop your engine just as well isn’t anywhere near as small e.g.
)FWIW I have a life raft permanently on the back seat, two handheld ELTs, a handheld radio and GPS all in one bag. But I would still not do a huge long water leg unless there was no (ATC allowed) option. This route is out of glide range and absolutely no way the Italians will let you fly nearer land even though there is zero traffic there. So that one has to be flown and I have done it a number of times. And same if going to say Ireland…
Whether I would do this in a rental plane, especially without a fuel totaliser, is another matter 
What’s wrong with the old “the aircraft doesn’t know it’s over water”-argument?
There is nothing wrong with it, at the contrary. The engine may quit any time, whether over water or over land. Absolutely. Only, over water there are fewer options, and the one obvious option requires a fair bit of equipment to stand any chance of offering survival.
I noticed the OP stated in an SEP, and yet there have been plenty twins ditched in open water, it would appear, through fuel mis-management. I have always tended to defy the flat earthers point of view that flying over water, at night, etc, is the stuff of lunatics. As stated by others, the engine can quit at any time, and either lady luck is with you, or not. If it chooses to do it over land, you have forests, cities, mountains, all of which can be more challenging for the pilot, and may very well not be surviveable. The water temperature does not fluctuate that much in the Northern Hemisphere, and unless fully equipped, the chances of survival, unless picked up quickly, are slim.
As I coast out, it does cross my mind, what if it quits. But I also do that on take off, over mountains, and on final over built up areas.
