Helicopter rotor blades
US4077741A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 18, 1976 |
| Grant date | Mar 7, 1978 |
| Priority date | — |
| Expiry date | May 18, 1996 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB64C27/463
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A helicopter rotor blade includes a rearwardly swept tip portion having a leading edge of aerofoil profile located forward of the leading edge of a central portion of the blade, and blended with a sharp tip edge of higher sweep magnitude than the leading edge and extending rearwardly to an extreme tip of the blade. A rearwardly swept trailing edge extends from a junction with the trailing edge of the central portion to the extreme tip so that the tip portion has a chord dimension greater than that of the central portion of the blade. In operation, the rotor blade utilizes a stable vortex dominated flow field created over the tip portion to provide operational advantages in respect of both a retreating and an advancing blade.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.