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Old 22nd April 2025 | 20:05
  #18 (permalink)  
moosepileit
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Joined: Jan 2008
: ATP+Mil
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From: USA
Originally Posted by applecrumble
Are you able to elaborate please Capn Bloggs
PMJI...
3 degree pencil beam weather radar, tilt down -8.5 degrees. Ground return distance is your absolute height. 10,000' paints ground at 10NM. 5000' paints ground at 5NM', enough to find an ILS GP.

Or, find the landing area radar reflectors and cook up your own final like back in the day.

Rule of 60, 1000'/NM is a 10 degree angle. Assumes an IRU stabilized radar airliner/big biz jet platform, otherwise compensate for deck angle.

It's just a radar tilt confidence check, in reverse. Mind the goats climbing hills and obstacles.
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