Technology and Operations
This forum is for discussing technological & operational matters pertaining to U-boats.
Re: Torpedo launch "von Hand"
Posted by:
Ken Dunn
()
Date: November 24, 2012 01:39PM
Hi bezukhov,
The launch of WWII U-boat torpedoes was meant to be initiated electrically from the bridge or control tower. Compressed air was the only method used in WWII U-boats to push the torpedo out of the tubes. WWII U-boat torpedoes were not designed to swim out themselves. Multiple simultaneous shots were actually controlled by a mechanism that initiated them at specific timed intervals (8 seconds at one point in the war). This was done to keep the torpedoes from interfering with each other in the water. When the command to fire multiple torpedoes was given the timing device was started and the torpedo launches were initiated at the predetermined intervals automatically by this electronic equipment.
In addition to the electrical firing mechanism there was a manual firing lever on each torpedo tube in case the electrical firing mechanism malfunctioned. If the electrical firing mechanism failed, the torpedo mate manually operated the firing lever on the tube to initiate the torpedo launch by compressed air. If multiple torpedoes were involved in the same shot (spread or salvo) the flashing lights you refer to alerted the torpedo mate who manually operated the firing lever on the torpedo tubes when it was time to launch each torpedo.
In some boats it was standard practice to have the torpedo mate push the manual firing lever on the torpedo tube at the same time the electrical firing mechanism was engaged because the electrical mechanism wasn’t all that reliable.
Though I don’t read German & the on-line translation program I used couldn’t translate the whole sentence, I suspect your Torpedo launch "von Hand" sentence is just saying the electrical firing mechanism malfunctioned and the torpedo mate in the torpedo room at the torpedo tube had to use the manual firing lever to initiate the launch by compressed air.
A torpedo stuck in the tube was a different problem but there were things they could do to try to free if the compressed air wasn’t enough to force it out of the tube.
There was a manual procedure to force out a torpedo that was stuck in a tube that involved using the mine ejector mechanism which injected the compressed air directly at the rear of the torpedo instead of behind the piston but most stuck torpedoes got stuck in the first place because one of the cables that were connected to the torpedo while it was in the tube didn’t retract when the launch was initiated and if it couldn’t he sheared off by compressed air it presented a serious problem. The outer torpedo tube door was open when the launch was initiated and if the torpedo moved far enough forward during the launch the outer torpedo tube door couldn’t be shut and the inner torpedo tube door was the only thing keeping water out of the boat and it wasn’t strong enough to do that at great depth so it rendered the boat somewhat crippled. The inner torpedo tube door couldn’t be opened so that something could be used to manually push the torpedo out either. The bow of boat could be dipped such that the considerable weight of the torpedo would aid in its sliding out of the tube but if that didn’t work the only way to get inside the tube to work on it was to surface the boat so the inner torpedo tube door could be opened and even then the “fix” given the limited room inside a torpedo tube might well have been beyond the capability of the crew at sea. Alternatively the bow could have been raised to use the weight of the torpedo to slide it back into the tube so the outer door could be shut but sliding a torpedo around inside the tube was also quite dangerous.
Unfortunately, those emergency procedures didn’t always work. I have seen a photo of a U-boat in dry dock with a torpedo warhead protruding out of one of its forward tubes.
Regards,
Ken Dunn
The launch of WWII U-boat torpedoes was meant to be initiated electrically from the bridge or control tower. Compressed air was the only method used in WWII U-boats to push the torpedo out of the tubes. WWII U-boat torpedoes were not designed to swim out themselves. Multiple simultaneous shots were actually controlled by a mechanism that initiated them at specific timed intervals (8 seconds at one point in the war). This was done to keep the torpedoes from interfering with each other in the water. When the command to fire multiple torpedoes was given the timing device was started and the torpedo launches were initiated at the predetermined intervals automatically by this electronic equipment.
In addition to the electrical firing mechanism there was a manual firing lever on each torpedo tube in case the electrical firing mechanism malfunctioned. If the electrical firing mechanism failed, the torpedo mate manually operated the firing lever on the tube to initiate the torpedo launch by compressed air. If multiple torpedoes were involved in the same shot (spread or salvo) the flashing lights you refer to alerted the torpedo mate who manually operated the firing lever on the torpedo tubes when it was time to launch each torpedo.
In some boats it was standard practice to have the torpedo mate push the manual firing lever on the torpedo tube at the same time the electrical firing mechanism was engaged because the electrical mechanism wasn’t all that reliable.
Though I don’t read German & the on-line translation program I used couldn’t translate the whole sentence, I suspect your Torpedo launch "von Hand" sentence is just saying the electrical firing mechanism malfunctioned and the torpedo mate in the torpedo room at the torpedo tube had to use the manual firing lever to initiate the launch by compressed air.
A torpedo stuck in the tube was a different problem but there were things they could do to try to free if the compressed air wasn’t enough to force it out of the tube.
There was a manual procedure to force out a torpedo that was stuck in a tube that involved using the mine ejector mechanism which injected the compressed air directly at the rear of the torpedo instead of behind the piston but most stuck torpedoes got stuck in the first place because one of the cables that were connected to the torpedo while it was in the tube didn’t retract when the launch was initiated and if it couldn’t he sheared off by compressed air it presented a serious problem. The outer torpedo tube door was open when the launch was initiated and if the torpedo moved far enough forward during the launch the outer torpedo tube door couldn’t be shut and the inner torpedo tube door was the only thing keeping water out of the boat and it wasn’t strong enough to do that at great depth so it rendered the boat somewhat crippled. The inner torpedo tube door couldn’t be opened so that something could be used to manually push the torpedo out either. The bow of boat could be dipped such that the considerable weight of the torpedo would aid in its sliding out of the tube but if that didn’t work the only way to get inside the tube to work on it was to surface the boat so the inner torpedo tube door could be opened and even then the “fix” given the limited room inside a torpedo tube might well have been beyond the capability of the crew at sea. Alternatively the bow could have been raised to use the weight of the torpedo to slide it back into the tube so the outer door could be shut but sliding a torpedo around inside the tube was also quite dangerous.
Unfortunately, those emergency procedures didn’t always work. I have seen a photo of a U-boat in dry dock with a torpedo warhead protruding out of one of its forward tubes.
Regards,
Ken Dunn
Subject | Written By | Posted |
---|---|---|
Snapshot, aal launch | NEEBLAMMERS | 09/06/2012 10:46AM |
Re: Snapshot, aal launch | SnakeDoc | 09/06/2012 11:49AM |
Re: Snapshot, aal launch | NEEBLAMMERS | 09/06/2012 12:34PM |
Torpedo launch "von Hand" | bezukhov | 11/23/2012 11:08PM |
Re: Torpedo launch "von Hand" | ROBERT M. | 11/24/2012 02:08AM |
Re: Torpedo launch "von Hand" | bezukhov | 11/24/2012 12:02PM |
Re: Torpedo launch "von Hand" | Ken Dunn | 11/24/2012 01:39PM |
Re: Torpedo launch "von Hand" | ROBERT M. | 11/25/2012 01:30AM |
Re: Torpedo launch "von Hand" | Ken Dunn | 11/25/2012 09:25AM |
Re: Torpedo launch "von Hand" | SnakeDoc | 11/25/2012 10:50AM |