Stunt pilots and fighter pilots who fly at high speeds in a downward-curving arc
ID: 1345452 • Letter: S
Question
Stunt pilots and fighter pilots who fly at high speeds in a downward-curving arc may experience a “red out,” in which blood is forced upward into the flier’s head, potentially swelling or breaking capillaries in the eyes and leading to a reddening of vision and even loss of consciousness. This effect can occur when the non-gravitational part of the centripetal acceleration exceeds 2.5g’s.
For a stunt plane flying at a speed of 350 km/h , what is the minimum radius of downward curve a pilot can achieve without experiencing a red out at the top of the arc? (Hint: Remember that gravity provides part of the centripetal acceleration at the top of the arc; it’s the acceleration required in excess of gravity that causes this problem.)
Explanation / Answer
V = 350- km/h = 350 x 5 /18 = 97.22 m/s
Force equation is given as
mg + 2.5 mg > mv2/r
3.5 x 9.8 > (97.22)2/r
r > 275.56 m