Blohm & Voss BV 138

The Blohm & Voss BV 138 Seedrache (Sea Dragon, but nicknamed Der Fliegende Holzschuh ("flying clog", from the side-view shape of its fuselage) was a World War II German trimotor flying boat that functioned as the Luftwaffe's main long-range maritime reconnaissance aircraft.

Design and development
A total of 297 BV 138s were built between 1938 and 1943. The aircraft was unusually powered by three engines, with one mounted high above the centerline driving a four-blade propeller, and one on each wing driving three-blade propellers. The pre-production prototypes and the BV 138 A-01 to BV 138 A-06, were powered by various makes of engines ranging from 485–746 kW (650–1,000 hp). The first standardized version, BV 138 B-1, was powered by three 880 PS (868 hp, 647 kW) Junkers Jumo 205D aircraft diesel engines. Unusual were the aircraft's twin boom tail unit, and gun turrets at the bow and the stern of the fuselage, as well as behind the central engine. These features together produced the aircraft's ungainly appearance.

The first of the 227 standard service variant, BV 138 C-1, began service in March 1941. Although various versions of the aircraft carried a variety of armament, the standard included two 20 mm MG 151/20 cannons, one in a power-operated bow turret and one in a power-operated stern turret, up to three 7.92 mm MG 15 machine guns, and a 13 mm (.51 in) MG 131 machine gun in the aft center engine nacelle. It could carry 500 kg (1,100 lb) of bombs or depth charges or, in place of these, up to 10 passengers. Several were later fitted with FuG 200 Hohentwiel low-UHF band search radar for anti-shipping duties. Some were converted for minesweeper role. The BV 138 MS variant, with the "MS", signifying Minensuch (German for mine-clearing, literally mine-search), carried a degaussing device, a hoop with the same diameter as the length of the fuselage and field-generating equipment, instead of weapons.

Variants

 * Prototypes
 * developed under Hamburger Flugzeugbau designation
 * Ha 138 V1 (D-ARAK) – First flight on 15 July 1937
 * Ha 138 V2 (D-AMOR) – First flight in August 1937
 * Ha 138 V3''' – Construction abandoned due to redesign.


 * Production
 * BV 138 A-01 to 06 – Operational testbeds
 * BV 138 A-1 – Flew reconnaissance during invasion of Norway
 * BV 138 B-0 – Officially entered service in October 1940
 * BV 138 B-1 – Entered service in November 1940
 * BV 138 B-1/U1
 * BV 138 C-1, also had minesweeper variant
 * BV 138 C-1/U
 * BV 138 MS – Minesweeping version.

Survivors
No complete BV 138s remain in existence. However, the wreck of one aircraft, sunk after the war in a British air show, was raised from the seabed of the Øresund Sound in 2000, and is on display at the Danish Technical Museum in Helsingør.

On 27 June 2012, two divers (Pascale Roibu and Iulian Rusu) found a Heinkel He 114 seaplane in Siutghiol Lake near Mamaia, Constanta, Romania. Recently near this Heinkel 114 the two divers also found pieces of a Blohm & Voss BV 138 seaplane.

In June 2013, a vessel from the Norwegian Geological Survey filmed a Blohm & Voss BV 138 at a depth of 35 m in Porsangerfjorden, Norway, not far from the WW2 German seaplane harbour in Indre Billefjord.