Enter the distance flown and the angle of deviation into the calculator to determine the track error. This calculator can also evaluate any of the variables given the others are known.

1 In 60 Rule Formula

The following formula is used to calculate the track error using the 1 in 60 rule.

E = (D * θ) / 60

Variables:

  • E is the track error (nautical miles)
  • D is the distance flown (nautical miles)
  • θ is the angle of deviation (degrees)

To calculate the track error, multiply the distance flown by the angle of deviation. Then divide the result by 60. This will give the track error in nautical miles.

What is a 1 In 60 Rule?

The 1 in 60 rule is a rule of thumb in aviation where a one-degree error in the flight path will produce a track error of approximately 1 nautical mile after 60 nautical miles of flight. It is used for quick mental calculations for navigation and error correction, particularly in visual flight conditions. The rule is based on the small-angle approximation of trigonometry.

How to Calculate 1 In 60 Rule?

The following steps outline how to calculate the 1 In 60 Rule.


  1. First, determine the distance flown (D) in nautical miles.
  2. Next, determine the angle of deviation (θ) in degrees.
  3. Next, use the formula E = (D * θ) / 60 to calculate the track error (E) in nautical miles.
  4. Finally, calculate the 1 In 60 Rule.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Distance flown (D) = 120 nautical miles

Angle of deviation (θ) = 45 degrees