posted by Lucy on .
You are piloting a small plane, and you want to reach an airport 450 km due south in 3.0 hours. A wind is blowing from the west at 80 km/h. What heading and airspeed should you choose to reach your destination in time?
V = -450 km / 3 h =-150km/h S(no wind)
The wind would cause the plane to fly
in a direction SOUTH of EAST.To nullify
the affect of the wind, the plane must fly in a direction SOUTH of WEST.We must reduce the affect of hor. component of the wind. It has no ver.
80 + x = 0,
x = -80 km/h WEST,
-150 + Y = -150,
Y = 0.
tanA = -150/-80 = 1.875,
A = 61.9 Deg S. of W. = 241.9 Deg CCW),
V = -80/cos241.9 = 170 km/h.
The plane must head 61.9 deg SOUTH of
WEST at a speed of 170 km/h.