The main reason for mounting the detector unit of a remote reading compass in the wingtip of an aeroplane or a helicopter tail-boom is: - ATPL

Question id 464 - General Navigation - ATPL - Airline Transport Pilot license

To maximize the units exposure to the Earth's magnetic field.

To ensure that the unit is in the most accessible position on the aircraft for ease of maintenance.

By having detector units on both wingtips, to cancel out deviation effects caused by the aircraft structure.

To minimize the amount of deviation caused by aircraft magnetism and electrical circuits.