Brantly B-1

infobox Aircraft
name = Brantly B-1
type = light coaxial-rotor helicopter


caption =
manufacturer = Brantly Helicopter Corporation
designer = N. P. Brantly
first flight = 1946
introduced =
retired =
status = abandoned
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more users =
produced =
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variants with their own articles =

The Brantly B-1 was a 2-seat, coaxial-rotor helicopter designed by N. P. Brantly and constructed by the Pennsylvania Elastic Company, Brantly's employer.

Design and development

In 1946, Brantly started flight testing the B-1 prototype (NX69125), which used a 150hp Franklin 335 engine in the fabric fuselage and two three-bladed rotors that rotated at 320 r.p.m. and were fitted coaxially. The collective, cyclic, and differential controls were enclosed in the rotor hubs and ran in an oil-bath. Each rotor blade weighed 5.5 kilos. It also had a fixed wheel undercarriage with a tailweel under the tailfin.

Unfortunately, the design was too heavy and complex and was abandoned.

pecifications

*Seats: 2
*Engine: 1 x 150hp Franklin 335
*Rotor diameter: 9m
*Length: 5.33m
*Height: 2.36m
*Loaded weight: 907kg
*Empty weight: 601kg
*Cruising speed: 182km/h
*Range: 640km

References

P. Lambermont "Helicopters and Autogyros of the World", 1958

R. Simpson "Airlife's Helicopter and Rotorcraft", 1998

External links

[http://www.aviastar.org/helicopters_eng/brantly_b-1.php "Brantly B-1" at www.aviastar.org]

[http://www.brantly.info/Brantly_Historical_2.htm Brantly Historical Photos]