Blohm & Voss BV 141

https://en.wikipedia.org/wiki/Blohm_%26_Voss_BV_141

The Blohm & Voss BV 141 was a World War II German tactical reconnaissance
aircraft. It is notable for its uncommon structural asymmetry. Although the
Blohm & Voss BV 141 performed well, it was never ordered into full-scale
production, for reasons that included the unavailability of the preferred engine
and competition from another tactical reconnaissance aircraft, the Focke-Wulf Fw
189.

In 1937, the German Air Ministry – the Reichsluftfahrtministerium (RLM) – issued
a specification for a single-engine reconnaissance aircraft with optimal visual
characteristics. The preferred contractor was Arado with the Ar 198, but the
prototype proved unsuccessful. The eventual winner was the Focke-Wulf Fw 189
Uhu; even though its twin-boom design using two smaller engines did not match
the requirement of a single engined aircraft. Blohm & Voss (Hamburger
Flugzeugbau) although not invited to participate, pursued as a private venture
something far more radical. The proposal of chief designer Dr. Richard Vogt was
the uniquely asymmetric BV 141.

The Plexiglas-glazed crew gondola on the starboard side strongly resembled that
found on the Fw 189, and housed the pilot, observer and rear gunner, while the
fuselage on the port side led smoothly from the BMW 132N radial engine to a tail
unit.

At first glance, the placement of weight would have induced tendency to roll,
but the weight was evenly supported by lift from the wings.

In terms of thrust vs drag asymmetry, the countering of induced yaw was a more
complicated matter. At low airspeed, it was calculated to be mostly alleviated
because of a phenomenon known as P-factor, while at normal airspeed it proved to
be easily controlled with trimming.

The tailplane was symmetrical at first, but in the 141B it became asymmetrical –
starboard tailplane virtually removed – to improve the rear gunner's field of
view and fire.


Role
Reconnaissance, light bomber

Manufacturer
Blohm & Voss

Designer
Richard Vogt

First flight
25 February 1938

Primary user
Luftwaffe

Number built
13–28

Three prototypes and an evaluation batch of five BV 141As were produced, backed
personally by Ernst Udet, but the RLM decided on 4 April 1940 that they were
underpowered, although it was also noted they otherwise exceeded the
requirements. By the time a batch of 12 BV 141Bs were built with the more
powerful BMW 801 engines, they were too late to make an impression, as RLM
already decided to put the Fw 189 into production. Indeed, an urgent need for
BMW 801 engines for use in the Fw 190 fighter aircraft reduced the chance of the
BV 141B being produced in quantity.

Vogt came up with several other asymmetric designs, including the piston-jet
P.194.01, but none of those were actually built.

Several wrecked BV 141s were found by advancing Allied forces. One was captured
by British forces and sent to England for examination. No examples survive
today.

Specifications (BV 141 B-02)

General characteristics
Crew: 3
Length: 13.95 m (45 ft 9 in)
Wingspan: 17.45 m (57 ft 3 in)
Height: 3.6 m (11 ft 10 in)
Wing area: 52.9 m2 (569 sq ft)
Empty weight: 4,700 kg (10,362 lb)
Gross weight: 5,700 kg (12,566 lb)
Max takeoff weight: 6,100 kg (13,448 lb)
Powerplant: 1 × BMW 801A 14-cyl. air-cooled radial piston engine, 1,147 kW
(1,538 hp) for take-off at sea level

Performance
Maximum speed: 368 km/h (229 mph; 199 kn) at sea level; 438 km/h (272 mph) at
5,000 m (16,404 ft)
Range: 1,900 km (1,181 mi; 1,026 nmi) maximum
Service ceiling: 10,000 m (33,000 ft)
Wing loading: 107.75 kg/m2 (22.07 lb/sq ft)
Power/mass: 0.204 kW/kg (0.124 hp/lb)




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