03934250 is referenced by 18 patents and cites 3 patents.

A precision hover and landing system for use in a helicopter is provided. A elevision camera system, an infra-red scanner and a passive radar antenna array are located on a three-axis gimbal mounted on the helicopter. An airborne radar angle tracking receiver and a ground-based transponder provide azimuth and elevation angle error signals for pointing the gimbal along the true line-of-sight to the desired landing area. A ranger unit provides range and range rate of change information.

Title
Helicopter blind landing and hover system
Application Number
5/477374
Publication Number
3934250
Application Date
June 7, 1974
Publication Date
January 20, 1976
Inventor
Oscar M Martin Jr
Bethesda
MD, US
Assignee
The United States of America represented by the Secretary of the Navy
DC, US
IPC
G01S 9/56
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