A method, an apparatus and a computer program product are provided for accurately determining the vertical speed of an aircraft in a manner independent of signals provided by an air data computer, an inertial reference system and an inertial navigation system. Initially, a first vertical velocity of...http://www.google.com/patents/US6430479?utm_source=gb-gplus-sharePatent US6430479 - Methods, apparatus and computer program products for determining the vertical speed of an aircraft
