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I recently watched the film Dunkirk (I highly recommend watching it).

Without wanting to give away too much information about the film, a Spitfire pilot is flying over part of The Channel. They lose their engine and state the sea looks calm and opt to ditch over bailing out.

Why would a Spitfire pilot choose to do this? Is ditching in the sea really safer than parachuting out?

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    $\begingroup$ Maybe the pilot tryed to reduce the distance to the beach or a nearby ship? $\endgroup$ – Peter Jul 25 '17 at 9:33
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    $\begingroup$ Parachuting over water may have a lot of risks e.g. chute not deploying, getting tangled in the chute and drowning. $\endgroup$ – Thomas Jul 25 '17 at 9:39
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    $\begingroup$ From watching the film last night, there wasn't a whole lot of altitude by this point. The pilot rather pointedly looked down at the sea before deciding to do for the ditch rather than the short jump with little chance of a canopy opening in time. $\endgroup$ – Snow Jul 25 '17 at 12:25
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    $\begingroup$ I thought he didn't bail because his canopy was jammed? $\endgroup$ – Jack Jul 26 '17 at 14:41
  • $\begingroup$ @Jack - he only discovered that his canopy had jammed after ditching - he successfully opened the canopy before changing his mind and taking the decision to ditch. $\endgroup$ – Snow Jul 27 '17 at 7:10
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Bailing out the cockpit during that era was neither an easy nor always a successful task. The pilot had to either roll the plane, open the canopy, and release themselves to the void, or if rolling wasn't possible, walk on the wing and jump.

That's inherently unsafe. Don't forget that you are not exiting a healthy plane. There might be smoke, debris, fire, propellers spinning, the tail that might cross your way out.

Read what happened to Hans-Joachim Marseille when he tried to bail out. Quote from Wikipedia:

the left side of his chest striking the vertical stabiliser of his fighter, either killing him instantly or rendering him unconscious to the point that he could not deploy his parachute.

Now, regarding ditching versus bailing out, I don't have any source to substantiate the chances of survival, because in the end, what matters is to get out of there alive. But I guess it depends on many factors, one of them being the sea state as they mention in the film.

Another one is the type of damage the airframe has sustained. It might be better to risk a "gentle" contact with the water if there is no "urgent reason" to leave the plane and you can ditch reasonably soon, than to exit the cockpit and increase the chance of being injured by anything that I've mentioned in the first paragraph.

Finally, it turns out that the choice heavily depends on the situation. I haven't seen the movie so besides the "sea state" I don't know the details. So provided that you are above a water mass capable of supporting the ditching idea, the factors mostly influencing the decision are:

  • Airframe condition
  • Altitude below you as Pete pointed out and Philip Johnson mentioned in his answer. Too low and you might not have time to deploy parachute.
  • Sea state
  • Time of day. You might want to touch water at a lower speed if you can't see it.
  • Position of allied forces and/or shore. Surviving the crash is one thing; being rescued a whole other.
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    $\begingroup$ And also whether you have the altitude to be able to drop out of the plane and deploy the parachute before you hit the deck... $\endgroup$ – Snow Jul 25 '17 at 12:21
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    $\begingroup$ @Pete indeed and that's why I've edited to add a list of factors that could influence the decision making process. $\endgroup$ – Stelios Adamantidis Jul 25 '17 at 12:55
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    $\begingroup$ +1 Good detailed answer, I'd also add, many a pilot successfully evacuated his aircraft and safely opened their chutes only to be killed by a strafing pass by the enemy aircraft as they floated down when they were a sitting duck. Unfortunately, killing the pilots was deemed more important. Aircraft could be replaced, pilots, not so easily. $\endgroup$ – Trevor_G Jul 25 '17 at 15:12
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    $\begingroup$ @Trevor Thanks. And indeed this was a threat and it constitutes a war crime! But the article in Wikipedia mentions that most of the pilots were having second thoughts about practicing this, so I wouldn't add it for the sake of brevity :) $\endgroup$ – Stelios Adamantidis Jul 25 '17 at 19:37
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    $\begingroup$ @Trevor I believe most pilots in WW2 didn't shoot at enemy pilots parachuting down, they didn't want the same to happen to them. You're more at risk of ground troops shooting at you, thinking you're part of a parachute assault (though the reverse also happened, Dutch ground troops failed to shoot at German paratroops, having been ordered not to shoot at pilots who'd jumped out of damaged aircraft). $\endgroup$ – jwenting Jul 31 '17 at 11:41
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In case of Spitfire, ditching in sea is not safer than bailing out. Spitfire XIV & XIX pilot's notes specifically states:

71 Ditching

(i) Whenever possible, the aircraft should be abandoned by parachute rather than ditched, since the ditching qualities are known to be very poor.

I don't think the advice would be any different in case of earlier models.

In such a case, the pilot's decision depends on his mental state under extreme stress. Maybe he was afraid of getting caught in the suspension lines of the chute, or hypothermia, which was quite possible if there is no timely rescue.

Or maybe he simply felt safer flying the aircraft than bailing out. It has to be noted that the pilots were not given any practical training in bailing out, which was hazardous at the best of times (even now with ejection seats). The description of a Spitfire pilot about bailing out goes like this:

... you loosened your straps, jettison the canopy and held the aircraft level, but trimmed forward and you let go the stick, which bunted the aircraft and you shot out and then the aircraft would drop away and as you dropped, you could pull your parachute...

No wonder the pilot preferred to be in the cockpit. This particular pilot forgot to jettison the canopy and his chute got caught in it, then escaped somehow and forgot to pull his chute before finally getting on ground in one piece. In that state, the pilot might have decided to take his chances rather than follow the notes.

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    $\begingroup$ Also, I've done ~1700 skydives and the lowest I've ever jumped out was ~2000 feet AGL. I have some friends who got special permission to jump from 1200 feet for a specific demo, but I really wouldn't to get out any lower than that - even with 'bad' ditching characteristics. $\endgroup$ – simon at rcl Jul 25 '17 at 15:27
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    $\begingroup$ Military airborne operations are done well below 1200 feet. Airborne school jumps are done at 1200, normal jumps are done at 800-1000 and real combat jumps are done at 500. Those are static line, so if you were manually deploying your chute, you simply have no time for delay, and in the case of combat jumps, no time for a reserve deployment $\endgroup$ – Kevin Jul 25 '17 at 16:47
  • $\begingroup$ Think it's worth noting that this is also a film based on true events. How true the events are is open to artistic license, and while the film is supposed to be a good film I haven't heard anything about the realism. So I wonder whether, if it was real, the pilot would've bailed but it makes a better cinematic scene if they ditch rather than bail. $\endgroup$ – mickburkejnr Jul 26 '17 at 8:16
  • $\begingroup$ Doing parachute training on static lines, the jump-master went through his speil as we took off, 'if there's a problem with the plane, and we're above 500ft, we just throw you straight out of the door!' Just what beginner wants to hear! $\endgroup$ – Neil_UK Jul 26 '17 at 15:10
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    $\begingroup$ @mickburkejnr not sure about the realism but the historical accuracy is ... close to 0. $\endgroup$ – Antzi Jul 26 '17 at 17:39
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Airplanes tend to float after ditching due to the air trapped in fuel tanks, wings and fuselage spaces, acting as a life raft which is very valuable. A ditched plane is also much more visible than a single pilot floating in the water, making rescue more likely.

The English Channel is also very cold throughout the year, being able to stay out of it by climbing on a wing will limit exposure and increase survival time dramatically. Spitfire pilots didn't have rafts, so this was an important consideration.

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  • $\begingroup$ Even if the aircraft stays afloat, there is the hazard of the aircraft flipping over, coming to rest inverted, leaving the pilot submerged and trapped under his floating aircraft. I'd speculate this is the "poor ditching qualities" referenced in one of the other answers. $\endgroup$ – Anthony X Sep 7 '17 at 1:58
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For baling out, height is the main criteria. If at a low height above the water there is a chance you will strike the water without the parachute being fully open, depending on the trajectory of the aircraft and the time it takes to get out of the cockpit.

Assuming there is enough height, I would have thought that ditching is more dangerous, because the impact forces could be high enough to knock the pilot unconscious against the gun-sight just ahead of his head, who will then drown when the aircraft sinks. Spitfires and Hurricanes were not known for floating for very long on the surface.

The procedure for ditching is not straightforward, but the whole aim is to minimize impact forces because these are a square of the speed (i.e. you double the speed you quadruple the forces felt), so its important to fly at the lowest controllable airspeed into wind (to reduce groundspeed) where possible but along the swell/waves so you don't crash headlong into a wave on touchdown. Try also to make the tail-plane the first thing that touches the water because the deceleration won't be as fierce as hitting wings or nose first. Also if its the nose or the wings first, on the Spitfire you could "submarine" (i.e. the flow of water over the wings would take the aircraft down before its even stopped). Undercarriage also must be up to prevent it making the aircraft flip or submarine on touchdown. Canopy open so it doesn't get damaged during the impact and then impossible to open quickly.

For whatever reason, in WW2 they were often feet underwater before the aircraft stopped moving so while you needed to be strapped in to survive the impact, you then had to unstrap pretty quickly and make your way to the surface.

I haven't seen the film, but based on the large number of WW2 biographies I have read, I think that in reality, given it is your own life on the line, and that you most likely haven't parachuted before, its entirely your own personal preference based on your own personal understanding and fears.

My personal view is that if you are doing much over 60mph in a small aircraft at touchdown in a ditching then the outcome is probably not going to be pretty, even 70mph may well make a big difference and 80 or 90 would most probably kill you. I'm not saying you can't survive higher speeds, but if you do then you are very lucky. You only have to read accident reports to understand that if you don't get the speed right, e.g. ditch downwind, or not at the minimum speed, you will be dead. This information only heightens my respect to the people who flew in wartime.

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    $\begingroup$ I know Captain Sullenburger survived a ditching at I think it was something like a 140 knot touchdown, but that was an airliner, not a Spitfire with a gunsight inches from your head. I think he went as slow as he could, got the tail in the water first and the engines managed to decelerate the aircraft without making the nose go under, and it wasn't damaged enough to sink immediately. So the above comment about 60mph doesn't apply. It was a combination of skill, luck and extreme coolness under pressure that saved Captain Sullenburgers day. $\endgroup$ – Philip Johnson Jul 26 '17 at 10:43
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    $\begingroup$ An A320 is not a "small" aircraft by anyone's standards. The stall speed of a heavy A320 (i.e.with a full fuel load) is, amazingly, (or not) about the same as Sullenburger's touchdown speed - somewhere in the range of 110 to 140 knots. The stall speed of some marks of Spitfire is as low as 40 knots, not 140. $\endgroup$ – alephzero Jul 26 '17 at 23:35
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    $\begingroup$ I didn't say the A320 was a small aircraft... I kinda got ahead of myself when I was writing the bit about ditching and added the comment about the A320, then went back and adding SMALL aircraft in my main text because I was trying to be clear. Shouldn't have added the A320 comment I guess because it doesn't apply to this question. Oops! $\endgroup$ – Philip Johnson Jul 27 '17 at 8:38
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    $\begingroup$ So, a Supermarine would submarine? $\endgroup$ – Agent_L Jul 27 '17 at 11:35
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In this very specific case, he was close enough to safe shores that the glide path provided significant benefit. Ditching would allow him to get significantly closer to safety than jumping.

So looking at the short term, jumping may have been safer, but looking at the long term, ditching was seen as safer even once you account for the fact that ditching itself may be less safe than jumping.

No pilot decision is made in a vacuum, however, and as pointed out by many others there were many reasons for this decision that wouldn't necessarily apply generally or in other situations.

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protected by Community Sep 5 '17 at 18:34

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