The Focke-Achgelis Fa 330 Bachstelze (English: Wagtail) is a type of rotary-wing kite, known as a rotor kite. They were towed behind German U-boats during World War II to allow a lookout to see further. About 200 were built by Weser Flugzeugbau.[2]
Fa 330 Bachstelze | |
---|---|
General information | |
Type | Rotor kite |
Manufacturer | Focke-Achgelis GmbH |
Number built | 200[1] |
History | |
First flight | August 1942 |
Development
editBecause of their low profile in the water, submarines could not see more than a few miles over the ocean. To solve this, the German admiralty considered a number of different options, including a folding seaplane (Arado Ar 231). In the end, they chose the Fa 330, a simple, single-seat autogyro kite with a three-bladed rotor.[1]
The Fa 330 could be deployed to the deck of the submarine by two people and was tethered to the U-boat by a 150 m (490 ft) cable.[3][2] The airflow on the rotors as the boat motored along on the surface would spin them up. The kite would then be deployed behind the U-boat with its observer-pilot aboard, raising him approximately 120 meters above the surface and allowing him to see much farther — about 25 nautical miles (46 kilometres), compared to the 5 nautical miles (9.3 kilometres) visible from the conning tower of the U-boat. If the U-boat captain were forced to abandon it on the surface, the tether would be released and the Fa 330 would descend slowly to the water.[1]
When not in use, the Fa 330 was stowed in two watertight compartments aft of the conning tower. In calm weather and sea, the assembly and disassembly steps could each be completed in approximately four minutes. In heavier weather, recovering (winching the Fa 330 back to the deck), dismantling, and stowing the Fa 330 took approximately 20 minutes and was a difficult operation.
Focke-Achgelis proposed a powered version of the Fa 330, the Fa 336, but the design never made it to the hardware phase.[4]
Operational history
editAs Allied air cover in other theatres of the war was considered too much of a threat, only U-boats operating in the far southern parts of the Atlantic, the Indian Ocean and the Gulf of Aden[2] used the Fa 330. Despite its advantages, the use of the Fa 330 resulted in only a single sinking when U-177 used one to spot, intercept and sink the Greek steamer Efthalia Mari on 6 August 1943.[5]
The Allies came into possession of an Fa 330 in May 1944 when they captured the U-852 intact.[6] After the war, the British government did successful experiments towing Fa 330s behind ships and jeeps, but the development of the helicopter quickly occupied the attention of the military.
U-boats that deployed Fa 330 kites included at least U-177, U-181, and U-852. Otto Giese wrote, "Our boat was rigged with a Bachstelze. This was a small, single, piloted helicopter attached to a 150 metre long steel cable and lifted into the air by the speed of the boat while the cable was gradually reeled out. From his position aloft, the pilot had a 360-degree view and could report any vessels."[7]: 183–184
Legacy and influence
editThe Fa 330 directly inspired Igor Bensen's interest in small autogyros which culminated in the Bensen B-8 and other modern autogyros.
In February 2013, Aviation Week and Space Technology reported that L-3 Communications was testing its Valkyrie, an unpowered, tethered autogyro that weighs 210 pounds (95 kg), which is intended to serve as a cheap alternative to a shipborne helicopter. Valkyrie is designed to hover as high as 5,000 feet (1,500 meters) but is envisioned to operate typically at 500 to 1,000 feet (150 to 300 meters), offering a 28-to-39-mile (45-to-63-kilometre) field of view. L-3 stated that naval vessels could easily be retrofitted with this system.[8]
Surviving aircraft
editDenmark
edit- 100032 – On static display at Egeskov Castle in Kvaerndrup, Faaborg-Midtfyn.[9]
France
edit- 100150 – On static display at the Le musée de l'Air et de l'Espace in Paris. This airframe was restored using parts from Wk. Nr. 100115 or Wk. Nr. 100145.[10]
Germany
edit- 100042 – On static display at the Deutsches Museum in Munich.[11][12]
- 100345 – On static display at the Deutsches Technikmuseum in Berlin.[13][14]
- 100406 – On static display at the Hubschraubermuseum Bückeburg in Bückeburg.[15][16]
United Kingdom
edit- 100143 – On static display at the Imperial War Museum Duxford in Duxford.[17][18]
- 100503 – On static display at the RAF Museum Cosford in Cosford.[19][16]
- 100509 – On static display at the Science Museum at Wroughton in Swindon.[20][18][16]
- 100545 – On static display at the Fleet Air Arm Museum in Ilchester.[21]
- 100549 – On static display at the Lashenden Air Warfare Museum in Ashford.[22]
United States
edit- 60133 – On static display at the Steven F. Udvar-Hazy Center in Chantilly, Virginia.[23][16]
- 100463 – On static display at the National Museum of the United States Air Force in Dayton, Ohio.[24][25]
Specifications
editData from Aircraft of the Third Reich [26][27]
General characteristics
- Crew: 1
- Length: 4.42 m (14 ft 6 in)
- Empty weight: 68 kg (150 lb)
- Max takeoff weight: 148 kg (326 lb)
- Main rotor diameter: 7.32 m (24 ft 0 in)
- Main rotor area: 42 m2 (450 sq ft) 3-bladed rotor
Performance
- Cruise speed: 40 km/h (25 mph, 22 kn) on tow
- Never exceed speed: 80 km/h (50 mph, 43 kn) on tow
- Minimum control speed: 27 km/h (17 mph, 15 kn) on tow
See also
edit- Hafner Rotabuggy
- Man-lifting kite
- Petróczy-Kármán-Žurovec tethered helicopters
References
edit- ^ a b c Petite, Bob (April 2015). "Vertical Rewind: Spoils of War". Vertical Magazine. Archived from the original on 25 April 2015. Retrieved 25 April 2015.
- ^ a b c Munson 1978, p. 53.
- ^ Ford, Roger (2013). Germany's Secret Weapons of World War II. London, United Kingdom: Amber Books. p. 224. ISBN 9781909160569.
- ^ "Focke-Achgelis Fa 336".
- ^ Helgason, Guðmundur. "Efthalia Mari (Steam merchant) - Ships hit by U-boats - uboat.net". German U-boats of WWII - uboat.net. Retrieved 26 August 2011.
- ^ Focke-Achgelis Fa 330A-1 "Bachstelze" — Smithsonian Institution National Air and Space Museum article at the Internet Archive. Retrieved 3 May 2012.
- ^ Giese, O., 1994, Shooting the War, Annapolis: United States Naval Institute, ISBN 1557503079
- ^ Osborne, Tony, "The autogyro returns," Aviation Week and space Technology, February 25, 2013, p.26
- ^ "100032 at Egeskov Castle Jun 2014". EuroDemobbed. June 2014. Archived from the original on 3 October 2016. Retrieved 1 October 2016.
- ^ "Focke-Achgelis Fa 330-A-0 Bachstelze". Musée Air & Espace (in French). Retrieved 1 October 2016.
- ^ "Focke-Achgelis Fa 330 "Bachstelze", 1942". Deutsches Museum. Archived from the original on 5 June 2017. Retrieved 1 October 2016.
- ^ "Munich - Deutsches Museum, Germany". EuroDemobbed. Retrieved 1 October 2016.
- ^ "Flugzeuge und Flugkörper in der Luftfahrtausstellung des Deutschen Technikmuseums" (PDF). Stiftung Deutsches Technikmuseum Berlin (in German). December 2015. Retrieved 1 October 2016.
- ^ "Berlin - Deutsches Technikmuseum, Germany". EuroDemobbed. Retrieved 1 October 2016.
- ^ "Gyrocopters". Hubschrauber Museum. Archived from the original on 30 July 2019. Retrieved 1 October 2016.
- ^ a b c d "Aircraft Database". LPH2O. LPH2O.com. Archived from the original on 2 October 2016. Retrieved 1 October 2016.
- ^ "Focke Achgelis Fa-330". Imperial War Museums. IWM. Retrieved 1 October 2016.
- ^ a b Wilberg, Thomas. "Focke Achgelis FA 330 Bachstelze". The Virtual Aviation Museum. Thomas Wilberg. Archived from the original on 3 April 2009. Retrieved 1 October 2016.
- ^ "Focke Achgelis FA330". Royal Air Force Museum. Trustees of the Royal Air Force Museum. Retrieved 1 October 2016.
- ^ "An Fa-330 at Wroughton". Robroy. July 2004. Retrieved 1 October 2016.
- ^ "Focke Achgelis FA330A-1 (100545)". Royal Navy Fleet Air Arm Museum. Fleet Air Arm Museum. Retrieved 1 October 2016.
- ^ Matthews, Trevor. "EXHIBITS". LASHENDEN AIR WARFARE MUSEUM. Retrieved 1 October 2016.
- ^ "Focke-Achgelis Fa 330A-1 Bachstelze (Water Wagtail)". Smithsonian National Air and Space Museum. Archived from the original on 2 October 2016. Retrieved 1 October 2016.
- ^ "Focke-Achgelis Fa 330 Sandpiper". National Museum of the US Air Force. 16 April 2015. Retrieved 1 October 2016.
- ^ "AIRCRAFT, DRONES AND MISSILES AT THE NATIONAL MUSEUM OF THE U.S. AIR FORCE" (PDF). National Museum of the US Air Force. June 2016. Retrieved 1 October 2016.
- ^ Green, William (2010). Aircraft of the Third Reich. Vol. 1 (1st ed.). London: Aerospace Publishing Limited. p. 338. ISBN 978-1-900732-06-2.
- ^ "Focke-Achgelis Fa 330A-1". Archived from the original on 4 January 2008. Retrieved 23 April 2020.
Bibliography
edit- Munson, Kenneth (1978). German Aircraft Of World War 2 in colour. Poole, Dorsett, UK: Blandford Press. ISBN 0-7137-0860-3.
External links
edit- The FA 330 at NASM
- Helgason, Guðmundur. "The Bachstelze". German U-boats of WWII - uboat.net.
- "German Submarine-Borne Observation Rotor-Kite", Allied Intelligence Report
- Video of the assembly and operation of a Focke-Achgelis Fa 330 aboard a German U-boat on YouTube