What Happened To German U-Boat Helicopters?

Some U-boats carried aboard an ingenious flying contraption utilized for sea reconnaissance, a motorless autogyro that looks similar to a primitive helicopter.

A common problem encountered by U-boats hunting for targets out in the ocean was how far men could actually see using binoculars, usually no more than five nautical miles. It was soon realized that if a man could be sent higher, he could see much higher.

In 1941, this problem came to the attention of Focke-Achgelis, a German helicopter company. They soon realized that what was needed was a very small and light helicopter, but all engines proved to be too large and heavy. It was soon decided to make the craft engineless.

The design soon became the Focke-Achgelis Fa 330 ‘Bachstelze’ or Wagtail. The first prototype flew in German-occupied France in May 1942.

The Fa 330 was rather simple. Aboard the U-boat, it was stored on the deck in two watertight compartments. Then, a crew of 3 to 5 men could assemble it in minutes. The machine, once assembled, weighed only 67 kg. not including the pilot. It consisted of a seat and a frame with a skid undercarriage. It also had a main rotor of three blades that measured 7.31 meters in diameter. At the rear was a tail unit that featured German markings.

The submarine would move ahead into the wind, causing the rotors to turn, providing lift, and the craft would lift off into the air, tethered to the U-boat by a cable. The pilot had foot pedals and a joystick to maintain stability. Moreover, a communications table was built to the tether so that the crewmen could communicate in real-time using their headsets with an operator on the U-boat who also wore a headset.

The Fa 330 could maintain an altitude of 120 meters, allowing the observer to see about 25 miles in all directions in binoculars. A huge increase in range and enabling the U-boat to detect targets earlier and with greater range than normal. The craft would then be retrieved in the same manner that it was launched, by being winched back down to the launching table and disassembled. However, during emergencies, the pilot observer would pull a handle above his head that would detach the rotors and the cable that links him to the submarine. It then automatically releases a parachute, allowing him to land safely on the sea and await rescue.

Between 120 to 200 of these ingenious machines were manufactured, and a handful of these were actually used aboard U-boats at sea.

However, there was only one confirmed use of the Fa 330 that resulted in a kill on August 6, 1943, when U-177 used one to spot, track, and intercept the Greek steamer Efthalia Mari and sink it.