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Old 10-25-2006 | 09:11 AM
  #160  
Gordon Mc
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Default RE: Skymaster F-4E phantom

ORIGINAL: Miniflyer


ORIGINAL: bobber

Miniflyer - are you sure about 20 g at 120 mph and 500 foot radius? Looks like a decimal place slipped.

I'm pretty sure. 120mph are about 200kmph, which is 55meters/second. G's are velocity (in m/s) squared divided by radius (in meters). So radius is velocity squared divided by G's.

55^2 /20 gives me 151,25 meters radius. A bit more than 3 feet per meter, so this is close to 500ft.

Regards
Hank
What am I doing wrong then :

120 mph = 176 fps (based on 1mph = 1.467 fps)

A = v*v/r
= 176 * 176 / 500
= 61.952

since 1 G = approx 32 fps, 61.952 / 32 = 1.9 G

Gordon