Enter the take-off roll (m), the thinking time distance (m), and the resolution distance (m) into the Balanced Field Length Calculator. The calculator will evaluate the Balanced Field Length. 

Balanced Field Length Formula

The following formula is used to calculate the Balanced Field Length. 

  • Where BFL is the Balanced Field Length (m)
  • TO is the take-off roll (m) 
  • TTD is the thinking time distance (m) 
  • RD is the resolution distance (m) 

To calculate the balanced field length, sum the take-off roll, thinking time distance, and resolution distance together.

How to Calculate Balanced Field Length?

The following two example problems outline the steps and information needed to calculate the Balanced Field Length.

Example Problem #1

  1. First, determine the take-off roll (m).
    • The take-off roll (m) is calculated to be : 1000.
  2. Next, determine the thinking time distance (m).
    • The thinking time distance (m) is measured to be: 100.
  3. Next, determine the resolution distance (m).
    • The resolution distance (m) is found to be: 500.
  4. Finally, calculate the Balanced Field Length using the formula above: 


The values provided above are inserted into the equation below and computed.

BFL = 1000 + 100 + 500 = 1600 (m)

Example Problem #2

The variables required for this problem are provided below:

take-off roll (m) = 2000

thinking time distance (m) = 200

resolution distance (m) = 20000

Test your knowledge using the equation and check your answer with the calculator.

BFL = TO + TTD + RD = (m)