Blade profile for rotary wing of an aircraft
US4325675A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Dec 5, 1979 |
| Grant date | Apr 20, 1982 |
| Priority date | — |
| Expiry date | Dec 5, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S416/02
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
The present invention relates to a blade profile for rotary wing of an aircraft, comprising, between the leading edge and the trailing edge, a convex upper surface and a non-concave lower surface, wherein, at the point of maximum curvature of the leading edge, the radius of curvature Ro is approximately defined by the expression Ro=1.7 C. e.sub.max.sup.2, in which C represents the chord and e.sub.max the relative thickness of said profile and the portion of lower surface adjacent the leading edge extends to about 20% of the chord from said leading edge and presents a very small general curvature decreasing continuously in the direction of the trailing edge up to the point of minimum curvature of the lower surface. The invention is more particularly applicable to obtaining rotary wings, for example for helicopters, capable of very high performances both when hovering, and in high speed flight, as well as during manoeuvres.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.