TYPE: Transport, reconnaissance and mine-swiping floatplane
ACCOMMODATION: Crew of four to five
POWER PLANT: Four Junkers Jumo 205C opposed piston diesel engines, rated at 600 hp each
PERFORMANCE: 179 mph at 9,850 ft
COMMENT: The Blohm & Voss Ha 139 was an all-metal inverted gull wing floatplane. With its four engines it was at the time one of the largest float-equipped seaplanes that had been built. The inboard engines were mounted at the joint between the inboard anhedral and outboard dihedral wing sections, above the pylon-mounted floats.
The aircraft were flown by Deutsche Luft Hansa (DHL) on transatlantic routes between 1937 and 1939. Catapult-launched from an aircraft tender they were able to transport 500 kg of mail over a distance of up to 5,000 km.
On the outbreak of WW II, the planes were transferred to the Luftwaffe and used for transport, reconnaissance and minesweeping work over the Baltic Sea. They were not particularly suited for military use. After service with DLH, the Ha 139B was modified as the Ha 139B/Umbau (Reconstruction) with an extended glazed nose accommodating a navigator and a spherical Ikaria mount for a machine-gun. Further machine guns were mounted in the cockpit roof hatch and in lateral mountings on either side of the rear fuselage. The Ha 139B/Umbau was later modified into a mine sweeping (Minensuch) aircraft Ha 139B/MS fitted with a large magnetic sensing loop strung between the nose, floats, wing-tips, and tail unit.
Further development of the Ha 139 led to the land based version Blohm & Voss Bv 142 which had its first flight in October 1938 (Ref.: 24).
TYPE: Long-range maritime patrol aircraft
ACCOMMODATION: Crew of six
POWER PLANT: Four BMW 132H-1air-cooled radial engines, rated at 870 hp
PERFORMANCE: 232 mph at sea level
COMMENT: The Blohm & Voss BV 142 was a civil aircraft developed for the transatlantic airmail service, originally designed for the Deutsche Luft Hansa (DHL). The first prototype was flown on 11 October 1938. The aircraft had four engines mounted on a low inverted gull monoplane wing, high horizontal stabilizer, and a double vertical tail, based on the Blohm & Voss Ha 139 float plane.The wing center section was strengthened by a typical Blohm & Voss cross-girder, which consisted of a large-diameter pipe. This transverse tube (divided internally into five sections) also acted as a fuel tank. The center wing was metal-covered, while the outer wings were fabric-covered. The fuselage was of metal and had an approximately circular cross-section. Each main landing gear leg had dual wheels and was fully retractable, as was the tailwheel. The landing gear was hydraulically lowered and retracted.
Only four prototypes (V1 through V4) were built. These aircraft were tested by Lufthansa and used briefly in the postal service. However, the outbreak of WW II ended further development of the civilian project. Soon after, it was proposed to convert all four prototype BV 142’s to long-range maritime patrol aircraft. The BV 142 V2 thus underwent a trial modification. It was fitted with an extended nose section with extensive glazing (like the Heinkel He 111H-6), defensive armament (MG 15 machine gun in the nose, twin-beam positions, a ventral cupola, and a powered dorsal turret), a compartment for ordnance in the fuselage, and navigation and military radio equipment. The BV 142 V2 was redesignated BV 142 V2/U1 while the V1 was similarly converted. Both were used operationally from late 1940 and were posted to the Luftwaffe’s Second Surveillance Group. However, their performance was disappointing, and after only a few missions, they were withdrawn from service in 1942. The two other aircraft (V3 and V4) were used as transport aircraft and could transport 30 fully equipped soldiers over 4,000 km. The ultimate fate of V3 and V4 is unknown. It was later planned to use the V1 and V2 to carry the Henschel GT 1200C guided torpedo, but the plan was scrapped (Ref: 24).
TYPE: Rocket-powered high-altitude reconnaissance aircraft. Project
ACCOMMODATION: Pilot only in prone position in pressurized cabin
POWER PLANT: One Walter HWK 109-509 bi-fuel liquid rocket engine, rated at 1,650 kp at 40,000 ft
PERFORMANCE: 559 mph (estimated)
COMMENT: The rocket-powered high-altitude reconnaissance aircraft DFS 228 (Deutsche Forschungsanstalt für Segelflug, German Institute for Sailplane Flight) was designed to climb to altitudes up to 75,459 ft and was than – due to this extreme height – far beyond the operational limits of any other aircraft at its time.
The DFS 228 design was a mid-wing monoplane, using wood whenever possible, with the exception of the pressurized nose compartment, which was an all-metal construction. Fins were plywood covered, ailerons and rudder fabric covered. A landing skid was housed in the center fuselage and could be extended for landing. For take-off a “Mistel” (Mistletoe) pick a pack configuration with landing skids retracted on a carrier Dornier Do 217K was proposed. Equipped with Zeiss infrared camera the aircraft was to be used for powerless reconnaissance missions. To perform these missions the DFS 228 was carried to an altitude of 33,000 ft. After ignition of the Walter HWK 109-509 liquid-fuel rocket engine and separation from its carrier the aircraft was able to reach its service ceiling of app. 75,000 ft within five minutes. The actual reconnaissance mission was done in powerless flight. Descending to its release height of 33,000 ft the aircraft could cover a distance of app. 466 miles and another 218 miles until landing. In case of emergency the pressurized nose compartment, equipped with all life-supporting systems, could be jettisoned by means of four explosive bolts, the module descend to an altitude at which the pilot could survive without oxygen supply. The pilot was ejected through the front windscreen and at the same time a parachute was deployed to bring the pilot safely to the ground.
By the end of WW II several prototypes had been built. However, flight testing was only performed in a non-powered glide and a height of 33,000 ft resp.75,000 ft was not exceeded (Ref 17, 24).
TYPE: Medium-altitude tactical bomber
ACCOMMODATION: Pilot and bombardier/navigator
POWER PLANT: Two Rolls-Royce “Merlin” 76/77 liquid-cooled engine, rated at 1,710 hp each
PERFORMANCE: 361 mph at 28,000 ft
COMMENT: The de Havilland DH.98 “Mosquito” was a British multi-role combat aircraft with a two-man crew during WW II. It was one of few operational front-line aircraft of the era constructed almost entirely of wood and was nicknamed “The Wooden Wonder”. Originally conceived as an unarmed fast bomber, the “Mosquito” was adapted to roles including low to medium-altitude daytime tactical bomber, high-altitude night bomber, pathfinder, day or night fighter, fighter-bomber, intruder, maritime strike aircraft, and fast photo-reconnaissance aircraft.
When “Mosquito” production began in 1941, it was one of the fastest operational aircraft in the world. Entering widespread service in 1942, the “Mosquito” flew high-speed, medium or low-altitude missions against factories, railways and other pinpoint targets in Germany and German-occupied Europe. From late 1943, “Mosquito” bombers were formed into the Light Night Strike Force and used as pathfinders for RAF Bomber Command heavy-bomber raids. They were also used as “nuisance” bombers, often dropping “Blockbuster” bombs – “cookies” – in high-altitude, high-speed raids that German night fighters were almost powerless to intercept.
On 21 June 1941 the Air Ministry ordered that the last 10 “Mosquitoes”, ordered as photo-reconnaissance aircraft, should be converted to bombers. These 10 aircraft were part of the original 1 March 1940 production order and became the B Mk IV Series 1. The prototype flew for the first time on 8 September 1941.
The bomber prototype led to the B Mk IV, of which 273 were built: apart from the 10 Series 1s, all of the rest were built as Series 2s with extended nacelles, revised exhaust manifolds, with integrated flame dampers, and larger tail planes. Series 2 bombers also differed from the Series 1 in having a larger bomb bay to increase the payload to four 230 kg bombs. This was made possible by shortening the tail of the 230 kg bomb so that these four larger weapons could be carried. The B Mk IV entered service in May 1942.
In April 1943 it was decided to convert a B Mk IV to carry a 1,800 kg “Blockbuster” bomb (nicknamed “Cookie”). The conversion, including modified bomb bay suspension arrangements, bulged bomb bay doors and fairings, was relatively straightforward and 54 B.IVs were modified and distributed to squadrons of the Light Night Striking Force. 27 B Mk IVs were later converted for special operations with the “Highball” anti-shipping weapon
Total “Mosquito” production in all variants during WW II was 6,710 aircraft. Because the aircraft were made entirely from wood mainly furniture companies were involved in production. Fuselage shells, wing spars, special wood veneers, many of the other parts, including flaps, flap shrouds, fins, leading edge assemblies and bomb doors were also produced in High Wycombe, which was well suited to these tasks because it had a well-established furniture manufacturing industry (Ref.: 24).