Rule of 60
One tool used to estimate time/speed/distance problems is known as the rule of 60. Stated
simply, aircraft ground speed divided by 60 equals the distance (nm) traveled in one
minute. (Table 4.3-1)
Knots to NM/Min
Decimal Minute to Seconds
Table 4.3-1 Knots to NM per Minute/Decimal Minutes to Seconds
For example at 60kts the aircraft travels one nm a minute, at 120kts it travels two nm's a
Rule of 6
A related rule, the rule of 6 states that 1/10th of the aircraft's ground speed is the distance
it will travel in six minutes.
For example, at 300kts the aircraft will travel 30nm in six minutes.
The time required to cover a specified distance at a given (known) speed can be expressed
in the following formula: