So, what is the big deal about snorkels?

Anything I have read about Uboats says that snorkels were a major innovation that might have changed the war if they were introduced earlier.

But I just read in Wikepedia that they were first used in 1916, but it was thought that the drawbacks outweighed the advantages.

So, did the Germans have something new in 1943 that made them brilliant?

 

We must be reading different U-Boat books then...

The German Schnorchel was a response to the improvements that the British were making in their radar sets, namely the cavity magnetron and centimetric radar, and the increasing numbers of Allied ASW warships and aircraft. Early in the war, the British lacked these things, and the U-Boats could recharge their batteries and run on the surface practically undisturbed. By mid-war this had changed to the detriment of the Germans. Hence the advent of the schnorchel to allow the U-Boats to recharge their batteries with a reduced chance of detection.

Actually, The USS Alligator(1862) used a primitive form of a schnorchel to provide her crew with breathable air while submerged - as did the various Confederate submarines. US submarine inventor, Simon Lake, also used a primitive schnorchel to provide air for the gasoline engine he used for propulsion. IIRC, John Holland also used primitive schnorchels on his early submarines.

However, in the case of these early submarines & the World War I boats, the many drawbacks did outweigh the few advantages. Even in early World War II, this still held true.

The Germans refined the Dutch design, however, it was not these refinements that made it "brilliant," it was the advances made in ASW warfare that made the schnorkle not only "brilliant", but "necessary."

 

Your understanding is mostly correct. However, the air bubble was not intended for the crew, but as an air reserve for the diesel engine to draw on until the float disengaged(hopefully this occurred before causing the crew to much pain).

 

What about the exhaust from the diesel engines? Would that not be piped out through the snorkel as well?

 

Yes.

 

My cousin an ex submariner told me that travelling under diesel with a schnorkel can be an unpleseant experience. Waves splashing over the inlet valve cause the valve to close while the diesels are sucking air out of the bubble.

WW2 submarines were really submersible torpedo boats. They could only catch ships on the surface, as has been pointed out the snorkel allows the submarine to avoid detection. What the snorkel enables the electrirc batteries to recharge and is a preciondtion for subm,arines desined to operate mostly submerged e.g. Type XXI submarine - Wikipedia

 

Brilliant or not, all my reading gives me the impression that by late 1943, if a U-Boat didn't have a snorkel it didn't survive! This device, while imperfect, gave a sub some reasonable chance to evade destruction. Of course, by remaining underwater it compromised its ability to find Allied shipping.

My question has always been that after 1943 why did the KM even let a boat out without one?

And another question while we're on this topic, why did they continue with making Type VIIs and IXs with net cutters and deck guns? It seems to me that these things gave more water resistance so removing them would have made the boat at least somewhat faster underwater, plus the space saved by not having the deck gun ammo could have meant some more battery space.