| Patent Number |
Title Of Patent |
Date Issued |
| 5992793 |
Aerofoil |
November 30, 1999 |
| An aerofoil comprises a leading edge and a trailing edge which define a mean chord length, and the aerofoil having an inner or root end adapted for attachment to an aircraft, and an outer end which includes a tip which is adapted in use to divide the airflow into two generally equal vort |
| 5927948 |
Propeller |
July 27, 1999 |
| A propeller (10a) comprising a plurality of propeller blades (9a) each having a root end (11a) attached to the central propeller disc or hub (12a), an intermediate portion (13a) extending from the root end (11a) and having a generally aerofoil cross section extending chordwise between a |
| 5750891 |
Method and apparatus for determining the airspeed of rotary wing aircraft |
May 12, 1998 |
| A method and apparatus for determining the airspeed of a rotary wing aircraft having a sustaining rotor with a plurality of radially extending rotor blades for rotation about a substantially vertical axis comprises the steps of measuring an airflow sideslip angle established during r |
| 5492448 |
Rotary blades |
February 20, 1996 |
| A rotary blade includes a fixed boundary layer control device extending spanwise on a lower surface adjacent the trailing edge to improve the lift/thrust characteristics of the blade especially at positive incidence angles. It was discovered that expected detrimental effects at zero/ |
| 5205715 |
Helicopter rotor blades |
April 27, 1993 |
| Flow separation behind the notch region of a swept tip of a helicopter rotor blade is reduced by a plurality of boundary layer control vanes located adjacent a forwardly swept leading edge portion forming the notch region. |
| 5199851 |
Helicopter rotor blades |
April 6, 1993 |
| A helicoper rotor blade includes at its outer end a tip vane having a mean chord length greater than fifty percent of a chord length of a blade central portion and a span length greater than fifty percent of the blade chord which in operation generates two approximately equal strength ti |
| 5174721 |
Helicopter rotor blades |
December 29, 1992 |
| Flow separation behind the notch region of a swept tip of a helicopter rotor blade is reduced by features of the geometry and aerodynamic characteristics of the notch region itself. In particular it has been found beneficial for a forwardly swept leading edge portion to extend at an |
