Time of Flight

To find the time of flight, determine the time the projectile takes to reach maximum height. The time of flight is just double the maximum-height time.

Start with the equation:

vy = voy + ay t

At maximum height, vy = 0.
The time to reach maximum height is t1/2 =
- voy
ay
Time of flight is t = 2t1/2 =
-2voy
ay

Plugging in voy = vo sin(θ) and ay = -g, gives:
Time of flight is t =
2 vo sin(θ)
g

where g = 9.8 m/s2

The time of flight is also determined solely by the initial velocity in the y direction and the acceleration due to gravity.