04224669 is referenced by 109 patents and cites 9 patents.

A geographically referenced minimum safe altitude monitoring, indication and warning system involving use of a navigation computer in conjunction with a memory device storing predetermined minimum safe altitude data as a function of geographic location. The stored data takes into account both natural terrain and man made flight hazards in a mosaic of geographic grid sections covering the navigational territory of interest, and it either arbitrarily assumes in such data "worst case" flight conditions, or one or more actual current conditions of vehicle course, velocity and altitude change rate in providing the system output whether in an airplane, submarine or other vehicle so as to indicate to the pilot or warn the pilot of existing minimum safe altitude or imminent approach to an unsafe altitude.

Title
Minimum safe altitude monitoring, indication and warning system
Application Number
5/863077
Publication Number
4224669
Application Date
December 22, 1977
Publication Date
September 23, 1980
Inventor
Frank H Brame
Redmond
WA, US
Agent
Christensen O Connor Johnson & Kindness
Assignee
The Boeing Company
WA, US
IPC
G08G 5/04
G01C 5/00
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