General Discussions
This is the place to discuss general issues related to the U-boat war or the war at sea in WWII.
200 ft is too deep
Posted by:
kurt
()
Date: June 19, 2001 05:54PM
<HTML>We had a discussion of this on this board a few months back.
In WWII, a submerged sub could rarely be seen below periscope depth. Regardless of, and with all due respect for, everyone else\'s experience with recent systems, actual combat losses in WWII bear this out.
It is true that for WWII subs, especially U-boats, their no. 1 enemy was aircraft. But subs were mostly spotted on the surface, either by eye or mostly by radar. The vast majority of subs sunk by aircraft were sunk on the surface or just below - in the act of a crash dive.
One of the great ASW breakthru\'s for allied aircraft were the shallow-fused depth charges. It turned out that aircraft would come upon a surface U-boat, and then rush in to depth charge them. The U-boat in turn crash dived. The depth charges, normally set for 60 feet or so, would take so long in sinking to depth that the U-boat would get away. The shallow charge depth charges went off in only 10 - 20 feet of water, detonating sooner, while the boat was still nearby and submerging. They were devestating.
The only effective weapon a WWII aircraft had for attacking a U-boat at depth (below persicope depth) was the \'Fido\' acoustic torpedo. These were dropped \'into the wake of the submerging U-boat\'. They were not meant to be used against already deeply submerged U-boats, but submerging ones that were getting away. I doubt the acoustic head on a Fido would be able to acquire a boat already 200 feet down.
The north Atlantic tended to be rough, the lighting poor. Subs were painted dull, dark colors. I\'ve never heard of a report of a ASW aircraft sighting a sub at 200ft, let alone hearing of a successful attack. I would be interested in hearing of any such incident, if there ever was one. Do you have any specific U-boat attacks where they were sighted from the air at depths of 200ft?
In the Pacific, where the water tended to be clearer, and subs often operated in shallow, coastal waters, it was not uncommon for US subs to be \'bombed\' by Japanese airplanes while underwater. [These are referred to in the reports as \'bomb\'s but I presume they are depth charges]. The deepest I recall reading was 120ft. I never heard of an attack of a sub at 200ft.
Obviously, muddy conditions would make even 60 feet impenetrable.
I beleive the consensus on the board a while back was that while a sub might be recognized at persicope depth (especially if it\'s persicope was up and a wake visible) it was rare for a sub to be seen at 100~120ft, and they were essentially visible below that.
Aircraft found subs in WWII by radar, or seeing them on the surface, or perhaps some effect of them on the surface - an oil slick, a trail of air bubbles, or torpedo tracks. MAD and sonobouys came in later and were used less often. Airborne sightings on a fully submerged sub was rare.
And everyone, the temperature of discussion on this board is getting too high lately. Let\'s all cool it a bit, or we\'ll spoil the fun for everyone. </HTML>
In WWII, a submerged sub could rarely be seen below periscope depth. Regardless of, and with all due respect for, everyone else\'s experience with recent systems, actual combat losses in WWII bear this out.
It is true that for WWII subs, especially U-boats, their no. 1 enemy was aircraft. But subs were mostly spotted on the surface, either by eye or mostly by radar. The vast majority of subs sunk by aircraft were sunk on the surface or just below - in the act of a crash dive.
One of the great ASW breakthru\'s for allied aircraft were the shallow-fused depth charges. It turned out that aircraft would come upon a surface U-boat, and then rush in to depth charge them. The U-boat in turn crash dived. The depth charges, normally set for 60 feet or so, would take so long in sinking to depth that the U-boat would get away. The shallow charge depth charges went off in only 10 - 20 feet of water, detonating sooner, while the boat was still nearby and submerging. They were devestating.
The only effective weapon a WWII aircraft had for attacking a U-boat at depth (below persicope depth) was the \'Fido\' acoustic torpedo. These were dropped \'into the wake of the submerging U-boat\'. They were not meant to be used against already deeply submerged U-boats, but submerging ones that were getting away. I doubt the acoustic head on a Fido would be able to acquire a boat already 200 feet down.
The north Atlantic tended to be rough, the lighting poor. Subs were painted dull, dark colors. I\'ve never heard of a report of a ASW aircraft sighting a sub at 200ft, let alone hearing of a successful attack. I would be interested in hearing of any such incident, if there ever was one. Do you have any specific U-boat attacks where they were sighted from the air at depths of 200ft?
In the Pacific, where the water tended to be clearer, and subs often operated in shallow, coastal waters, it was not uncommon for US subs to be \'bombed\' by Japanese airplanes while underwater. [These are referred to in the reports as \'bomb\'s but I presume they are depth charges]. The deepest I recall reading was 120ft. I never heard of an attack of a sub at 200ft.
Obviously, muddy conditions would make even 60 feet impenetrable.
I beleive the consensus on the board a while back was that while a sub might be recognized at persicope depth (especially if it\'s persicope was up and a wake visible) it was rare for a sub to be seen at 100~120ft, and they were essentially visible below that.
Aircraft found subs in WWII by radar, or seeing them on the surface, or perhaps some effect of them on the surface - an oil slick, a trail of air bubbles, or torpedo tracks. MAD and sonobouys came in later and were used less often. Airborne sightings on a fully submerged sub was rare.
And everyone, the temperature of discussion on this board is getting too high lately. Let\'s all cool it a bit, or we\'ll spoil the fun for everyone. </HTML>
