Sperrbrecher

[Lord_of_Sofa 6,335]

During WWI and II all sides made extensive use of offensive and defensive minefields. To ensure a safe passage Minesweepers were sent out before other vessels to clear a path. But often enough not all mines were found, or a single mine would drift away. These made passing through a supposedly safe passage dangerous.

To ensure a safe passage for any folowing vessels the German navies of WW I and II employed special Sperrbrecher (eng. mine barrage breaker). These ships were tasked with sailing ahead of a convoy to detonate any remaining mines with their hull. During WW II these were converted merchant vessels up to 5000 BRT. They received a reinforced bow as well as additional protection for the crew such as a wooden deck cover to protect them against shock waves from detonating mines. 

Spoiler

Sperrbrecher 21

 

The cargo holds were filled with wood, barrels, cork ,and other buoyant material to prevent them from sinking. In fact this prove effective enough for the Sperrbrecher 11 "Belgrano" to return back to the harbor under his own power after suffering a heavy hit from a ground mine. The ship broke in two half, but managed to tow its bow back to port even though it hit another mine on its way back. It survived the war and rentered service under the GMSA. In 1946 it broke appart a second time after hitting a mine. Again it towed its own bow back to port.

Spoiler

Sperrbrecher 11 

 

to protect against enemy vessels and aircraft the Sperrbrecher received a relative heavy armament. Ranging from nothing at all up to 2 x 1 - 105/42, 6 - 37, 14 - 20, 8 - 86 rocket launchers, and 1 balloon (against low flying attackers).

Later in the war aircraft droped magnetic mines became a bigger threat. To deal with them a number a Sperrbrecher received a VES-Anlage. A device to create a magnetic field strong enough to trigger these mines. these devices were even installed on landing crafts to clear lakes and rivers.

Spoiler

Marinefährprahm Typ B as Sperrbrecher

Of over 100 Sperrbrecher converted, half were lost during the war.

[ArmourWorm 54]

Didn't British test something similar? Cork filled cargo ship? I seem to remember they didn't work all that well.

[Lord_of_Sofa 6,335]

1 minute ago, ArmourWorm said:

Didn't British test something similar? Cork filled cargo ship? I seem to remember they didn't work all that well.

No idea. I didn't find the time to read through the auxiliary units of the royal navy.

[Josephs_Piano 7,044]

11 minutes ago, ArmourWorm said:

Didn't British test something similar? Cork filled cargo ship? I seem to remember they didn't work all that well.

 

Q-ships often carried light wood, cork or even empty casks in their holds to provide additional buoyancy - overall they were not a particularly effective counter to u-boats.