PURPOSE: To protect a display part from vibration, by mounting a display housing receiving a display device to a cowling through a vibration damping member.

CONSTITUTION: The vibration on the side of the propeller main body 11 of an engine unit 19 is damped by seal members 22A, 22B to be transmitted to an upper cowling 21 and the vibration transmitted to the upper cowling 21 is further damped by mount rubbers 30, 34 being vibration damping members. Therefore, vibration is not almost or perfectly transmitted to the side of a display housing 31 and a display part 33. By this method, the display part 33 with a transmitter-receiver 25 connected thereto can be protected from vibration.