Definition

Used correctly, rules of thumb (sometimes know as “heuristics") can assist significantly in pilot decision making and understanding. A rule of thumb is a principle with broad application that is not intended to be strictly accurate or reliable for every situation. It is an easily learned and easily applied procedure for approximately calculating some value. It is particularly useful as a means of cross-checking or confirming the validity of information being displayed by aircraft navigation systems and flight management systems.

1 in 60 Rule

A 1 degree offset angle at 60 nm equates to 1 nm of displacement.

Speed/Distance/Time

Flying speeds that simplify mental arithmetic can help you in many ways, such as keeping retaining situational awareness during radar vectoring.

120Kts = 2nms/min

180Kts = 3nms/min