[Milsurplus] High & Mighty SCR-718

[b. smith]

    Although the SCR-718 was utilized quite dramatically in the "High and 
The Mighty"  while the distressed aircraft was at lower altitudes  and  the 
aircraft approached SFO, the main purpose of the SCR-718 was for use by the 
navigator to determine the aircraft's Absolute Altitude during the enroute 
cruise portion of the flights.  The Absolute Altitude  of the SCR-718 was 
compared with the Pressure Altitude(Standard Barometric altimeter set to 
29.92 inches)  to determine the difference in feet (usually a value of 
several hundred feet). This  "sounding" was entered into a formula to 
determine the aircraft's drift angle.  If you knew the aircraft's True 
Heading and Drift  Angle you could find your way to your destination. 
Pressure Pattern navigation was a great aid and augmented celestial 
navigation, it  had no boundaries or restrictions  and even worked great in 
the  polar regions. The process was developed by Dr. John Bellamy.


73 breck k4che