What is the minimum rate of climb required for takeoff on runway RWY 9 with an average groundspeed of 140 knots?

To determine the minimum rate of climb required for takeoff, you need to understand the relationship between groundspeed and the required climb gradient. The rate of climb can be calculated using the formula that considers the necessary climb gradient relative to the aircraft's groundspeed.

Typically, a 3.3% climb gradient is used for takeoff, which translates to a required vertical climb for every 100 units of distance traveled horizontally. With an average groundspeed of 140 knots, this translates into a horizontal distance covered in a given timeframe.

To calculate the required rate of climb:

1. Convert groundspeed to feet per minute (since there are 6076.12 feet in a nautical mile and there are 60 minutes in an hour):

• 140 knots = 140 x 6076.12 / 60 = 14,130 feet per minute approximately.

2. To achieve a 3.3% climb gradient, you would calculate 3.3% of the horizontal distance covered:

• Rate of climb required = 14,130 feet per minute x 0.033 (3.3%) ≈ 465 feet per minute.

However, for practical calculations and safety margins during takeoff, a higher rate of climb