WW2 Airplane Submarine: Can it Really Run Underwater?

[mrspeedybob]

This question may be impossible to answer without specific knowledge of vintage aircraft engines but maybe not.

How does this airplane...


come out of the wave running? It seems like running a piston engine underwater would result in ingestion of water and hydro-lock.

I'm not an engineer but I am professional automotive mechanic so I have a good understanding of reciprocating piston engine operating principals, at least as they are applied to cars.

 

[Borek]

I don't think it was underwater, more like it went through a splash. There wasn't necessarily much water there, probably mostly foam.

 

[OmCheeto]

This question may be impossible to answer without specific knowledge of vintage aircraft engines but maybe not.

How does this airplane...


come out of the wave running? It seems like running a piston engine underwater would result in ingestion of water and hydro-lock.

I'm not an engineer but I am professional automotive mechanic so I have a good understanding of reciprocating piston engine operating principals, at least as they are applied to cars.

Advanced plane on loan from England. Bond flew them.

After some googling:

CV-14 = USS Ticonderoga
Aircraft type: S-2E Tracker
Engines: 2 x 1525 hp air cooled radial piston design
Manufacturer: Grumman
Role: ASW aircraft (boooooo!)

http://www.navsource.org/archives/02/14.htm

How not to launch an aircraft in heavy seas: an S-2E Tracker is launched from USS Ticonderoga (CVS-14). As Brian Wolfe and Gil Sharp recall, this happened circa April-May 1971, en route from the Philippine Islands to Japan.

Roger Ozbolt comments: "I remember when it happened, it was our Lieutenant V-2 division officer who was the pilot, the plane was making a mail run. He said after the plane went through the wave it stammered and sputtered for a few seconds then smoothed out, he said they had about 4" of water in the cockpit. [...] it's a wonder that it didn't go down."

I know nothing of airplanes, but am familiar with running diesel engines underwater.

And I'm 99% certain that Borek is correct, in that it was just a splash.

 

[SteamKing]

Air-cooled aircraft radial engines are designed to catch their intake air from behind the engine somewhere, and, more often than not, run it through a turbo-charger before it goes into the cylinders. I think this is what kept the engine running momentarily until the aircraft cleared the wave. All in all, these guys in the aircraft were lucky.

 

[mrspeedybob]

Air-cooled aircraft radial engines are designed to catch their intake air from behind the engine somewhere, ...

Ahh, that makes perfect sense. The airplane pulls a pocket of air into the wave with it. Since the intake is behind the engine it is positioned in, and able to run on the air in that pocket for a few meters until it clears the wave.

Thanks :thumbs:

I'm sure it's no accident that the intake is positioned in the air that the plane is pulling along with it. I'm guessing that the purpose of this placement is because the air not moving relative to the plane would be at a higher pressure then the air that is (Bernoulli principal). Is that correct, or is there a different for the placement of the intake behind the engine?

 

[SteamKing]

Well, one reason I can think of is you don't want to block the flow of air coming in the front of the radial engine, since that air flow provides the cooling for the cylinders. This is even more important for radials which have two or more rows of cylinders. The S-2E used Wright Cyclone R-1820 engines (9 cylinders each), the same engines used to power B-17 bombers.

Another reason is space. The exhaust and intake plumbing can fit better behind the engine, especially if turbocharging is employed.