The BERP rotor blade design was developed under the British Experimental Rotor Programme. The initial BERP rotor blades were developed in the late 1970s to mid-1980s as a joint venture programme between Westland Helicopters and the Royal Aircraft Establishment. The goal was to increase the helicopters lifting-capability and maximum speed using new designs and materials.
BERP III designs have a notch toward the outer end of the rotor blade, with a greater amount of sweepback from the notch to the end of the blade compared to inboard of the notch.
The initial programme, BERP I, studied the design, manufacture and qualification of composite rotor blades. This resulted in producing new main rotor and tail rotor blades for the Westland Sea King. Following on from the first, the second programme, BERP II, analysed advanced aerofoil sections for future rotor blades. This fed into the BERP III programme that culminated in a technology demonstration on a Westland Lynx helicopter. In 1986, a Lynx specially modified registered G-LYNX and piloted by Trevor Egginton set an absolute speed record for helicopters over a 15 and 25 km course by reaching 400.87 km/h (249.09 mph). Following the successful technology demonstration, the BERP III blade went into production.
Current applications are:
- BERP III:
- AgustaWestland AW101
- Upgraded Westland Super Lynx
- BERP IV:
- AgustaWestland AW101
- VH-71 Kestrel