Question 1168647
v = w*r where w is the angular velocity and r is the radius
v = 195 m/s
The plane completes a half circle in 45 s.  
Since a half circle is equal to {{{pi}}} radians, we have:
r = 195/({{{pi}}}/45) = 2793 m
The centripetal acceleration is v^2/r = 195^2/2793 = 13.63 m/s^2