I’ve written a few blogs in the past about IEDs placed under train tracks, that the weight of the train triggers. As a reminder:
- In the US Civil War, in 1864, the Union Army designed an IED (a “rail torpedo”) that initiated when a train ran over a rail , pressing down on a gun trigger that caused the device to function.
- Another IED design was used in the Franco-Prussian War, in 1870, with the rail pressing on an artillery fuse to initiate the charge.
- In the Boer War, in 1901, Jack Hindon used devices under railways to attack British trains, using an upturned Martini Henry gun lock, with the rail bending under weight to press on the trigger which initiated an explosive charge.
- In WW1, ordnance specialist “Bimbashi” Garland designed and deployed similar devices, again using an upturned gun trigger, and used by Lawrence of Arabia to great effect against the Ottoman Turk trains in Arabia.
I’m glad to say I’ve now found a similar device, with a great story, from WW2. The use of the IED was effectively the ONLY US ground combat operation on the Japanese homeland in the entire war. (Noting that the attack took place in southern Sakhalin, which was considered a Japanese home island at the time) .
Late in the war, US Navy submarines began to patrol very aggressively close to the Japanese mainland. One of the subs was the USS Barb, skippered by Commander Eugene Fluckley. The patrol in question started on 8 June 1945 and involved a variety of attacks including, unusually, firing rockets at Japanese targets from the deck of the surfaced submarine. After noting considerable Japanese railway activity on a railway line near the shore, a plan was developed to blow up a train by putting a team ashore at Karafuto from the submarine.
An improvised device was carefully designed. As far as I can make out it was as follows:
- The main charge was a 55lb super-Torpex “scuttling charge” held in reserve on the submarine for scuttling the sub in an emergency. The blasting caps used must have been the ones meant to be used with this charge.
- Power was provided by two dry cell batteries.
- The switch was a microswitch removed from some electronic equipment on board.
- The batteries and circuitry were mounted inside an oil-can to protect it from the elements. Included was a “test circuit” to ensure safety.
The crew made careful calculations to estimate the deflection of the railway line (7/10″, which was adjusted on the operation itself to 1/4″) and made an improvised gauge to help the setting of the switch. They also made improvised shovels to help bury the charge under the rails. An eight man team was put ashore in inflatable boats and made their way (with one or two adventures) towards the track.
The charge was successfully initiated by a 16 carriage train and all the saboteur group escaped unharmed. Commder Fluckley ended the war as the most decorated officer in the Navy.