High do planes and helocopters have to be
Fixed wings have to stay 1,000 feet above populated areas, and 500 feet above any vessel or waterway. Rotary wing (helos) don't have any height restriction, unless they're causing a disturbance or endangering vessels or persons.
The height over water doesn't apply to amphib planes taking off and landing.
Alan
BoatCop (http://www.boatcop.com)
[This message has been edited by Boatcop (edited July 09, 2002).]