| BV 238 | |
|---|---|
 The prototype BV 238 V1 in June 1944 | |
| General information | |
| Type | Flying boat |
| National origin | Nazi Germany |
| Manufacturer | Blohm & Voss |
| Status | Retired |
| Primary user | Luftwaffe |
| Number built | 1 (with 2 incomplete prototypes)[1] |
| History | |
| First flight | March 1945[2] |
TheBlohm & Voss BV 238 was a large six-enginedflying boat designed and built by theGerman aircraft manufacturerBlohm & Voss. Developed during theSecond World War, it was the heaviest aircraft ever built when it first flew in 1944, and was the largest aircraft produced by any of theAxis powers during the conflict.[3]
Development of the BV 238 started in January 1941 in response to aReichsluftfahrtministerium (RLM/German Aviation Ministry) request for a long range multipurpose flying boat. The resulting design drew upon the firm's existing large six-engined flying boat, theBV 222Wiking, but was considerably larger and featured numerous refinements, such as to itselevator andfloat configuration. To gather flight data on its proposed configuration, a quarter-scale model, theFGP 227, was commissioned, but was so delayed that it provided little benefit. The company received an order for four prototypes, the construction of which commenced during January 1944.
During March 1945, flight testing of the first prototype commenced. Two months later, this prototype was sunk while moored atLake Schaal after being strafed by Allied aircraft. While recovery was thought to be possible, the end of the conflict and the refusal of the Allies to permit continued aircraft development in Germany at that time meant that work on the programme was abandoned. This included work on a land-based derivative of the flying boat, designatedBV 250, which ultimately never flew.
At the start of theSecond World War, the design team at the German aircraft manufacturerBlohm & Voss were largely preoccupied by the development of theBV 222Wiking, a large six-enginedflying boat.[4] However, during 1940, the firm's designer opted to start work on an even larger flying boat under the designationP 200 that would be suitable for the future long distance routes (particularlytransatlantic ones) of the Germanflag carrierDeutsche Luft Hansa. Furnished with eight engines, this vast flying boat was anticipated to have had a loaded weight of 200,000 kg (440,925 lb), a range of 8,600 km (5,300 mi) and a passenger capacity of 120.[5]
During January 1941, work on the P.200 proposal was suspended in order to focus on the fulfilment of a new request issued by theReichsluftfahrtministerium (RLM/German Aviation Ministry) for a long range multipurpose flying boat.[5] In the following months, the design team worked on an initial four-engined design for what would become theBV 238, however, it was abandoned by mid 1941 due to the lengthy timescale involved in developing suitable domestic engines to power it. Instead, in July 1941, work commenced on a fresh design that, while being considerably larger than the BV 222, shared numerous features as well as its general layout.[5] This design was warmly received and a development order calling for the completion of four prototypes was promptly issued to the firm.[6]
While its similarities to the BV 222 meant that some useful data could be obtained from this existing flying boat, it was felt that some aspects were too dissimilar for this arrangement to be fully sufficient.[7] Accordingly, an approximately quarter-scale model of the BV 238 was commissioned to test the long and slim hull design, which was largely original. Built by theFlugtechnische Fertigungsgemeinschaft GmbH (FGP) inPrague and designatedFGP 227, this scale model did not arrive (as a result of several factors, including sabotage and damage sustained during itsmaiden flight) until September 1944, too late to contribute any data to the program.[8][9]
During 1942, the construction of the variousjigs and components for the BV 238 commenced; fabrication of the firsthull started in January 1944.[7] Production work continued even as many other aircraft programmes were cancelled due to Germany's declining position in the conflict; one factor in this decision was that, aside from the materials involved, little of the BV 238's supply chain competed with that of fighter aircraft production.[10] Although extensive defensive armament was planned, the first prototype,BV 238 V1, lacked any upon its completion in March 1945 (these armaments were planned to be installed at a later date). While the flying boat had been designed to fulfil a military specification, the design team had undertaken some work towards its prospective civilian applications as well.[11]
By the end of March 1945, after completed only four test flights, BV 238 V1 was declared to be fit for service.[2] After only two months of flights, this aircraft wasstrafed and partially sunk while moored onLake Schaal, several miles to the east ofHamburg.[2] One wing remained above water, which was later salvaged. Following the end of the conflict, the Allies refused to let the flying boat be restored so it was taken out to deeper water and sunk.[12] Two additional flying boats were mid-construction, but these were also never completed.[2]
The BV 238 was an extremely largeflying boat of conventional aerodynamic design, but bearing the usual B&V structural hallmarks of all-metal construction with a tubular steel wing mainspar which also functioned as the armoured main fuel tank. Of the era, only the earlierTupolev ANT-20, theMartin XPB2M-1 and the laterHughes H-4 had a bigger wing span. However, the BV 238 would be the heaviest yet flown, at 100 tonnes (220,000 lb) fully loaded.[citation needed]. Principal differences between the BV 238 and the preceding BV 222, aside from the formerly greater size and some hydrodynamic improvements, included a revisedelevator and an alternativefloat arrangement.[2]
The hull had an unusually long and slim planing bottom, of essentially two-step design but with a row of smaller auxiliary steps behind the main one. A large nose door opened onto its cavernous interior, with the main crew cabin immediately above and behind it. For ease of production, design features were kept relatively simple while no use ofmagnesium was made for any part of the airframe.[2]
The wing was of straight, constant-chord form with tapered outer sections. Auxiliary floats were integrated into underside panels of the outer sections and could be retracted to lie flush with the wing. A catwalk ran internally along the wing in front of the tubular steel main spar, providing access to the engines in flight.[13] It was powered by sixDaimler-Benz DB 603 liquid-cooled invertedV12piston engines, capable of producing up to 1,287 kW (1,750 hp). These engines were installed innacelles that were arranged along theleading edge of the wing's centre section.[1]
Data fromAircraft of the Third Reich Vol.1,[1]Blohm & Voss Bv 222 "Wiking" – Bv 238[17]
General characteristics
Performance
Armament
Aircraft of comparable role, configuration, and era
Related lists
