Outboard Motor Sounds
50 HP Outboard Motor
This recording is of a 50 HP outboard engine starting up and going into gear. You will hear a "ratchet" like sound that is associated with the gears starting to engage.
Sound courtesy of Tom Kieckhefer. Released under Creative Commons License, non-commercial attribution.
Outboard motors are found on small boats that are popular in coastal waters. The propeller of an outboard motor is what creates sound. On smaller boats, like a zodiac, the small propeller produces a cavitation noise which is at higher frequencies than larger vessels. The smaller propellers also produce higher rotation rates which also causes the propeller to make higher frequency noises. A zodiac, for example, can produce frequencies as high as 6300 Hz.