The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 30, 1988
Filed:
Jun. 02, 1987
Wolfgang Hassenpflug, Freiburg, DE;
Rainer Schwable, Garbsen, DE;
Litef GmbH, Freiburg im Breisgau, DE;
Abstract
A method for determining the horizontal airspeed of a helicopter in the high speed (v.sub.e >20 m/s) range. Pitch angle and the longitudinal control signals are recorded by sensors such as an inertial navigation system and a potentiometer connected to the pilot's control lever. Equivalent speed signals are calculated from the measured pitch angle and longitudinal control signals by means of calibration equations. These signals are then filtered and weighted. The horizontal airspeed is then derived from the sum of the weighted signals divided by the sum of weighting factors k.sub..theta. and k.sub..delta.x determined in accordance with the sensed pitch angle and longitudinal control signals. The horizontal velocity signal may be filtered, if necessary.