The Brantly B-1 was a 2-seat, coaxial-rotor helicopter designed by Newby O. Brantly

Newby O. Brantly

Newby Odell Brantly was an inventor, engineer and entrepreneur who founded the Brantly Helicopter Corporation.-Life:...

 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 O-335 engine in the fabric fuselage and two three-bladed rotors that rotated at 320 rpm 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 tailwheel under the tailfin.

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

Specifications

• 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

External links

Brantly B-1 at www.aviastar.org

Brantly Historical Photos