Dunno where all these percentages came from in the Huey - like Arm Out says, it was 6600RPM down to 6400, or 6000 under some-circumstances-or-other which I can't remember after 21 years. The transit from Seeb to Khasab could be done in a one'r (with about 10% reserves) at FL100 with the RPM beeped down. However, most of the Rhodie's had a thing about flying above 2000 feet (something to do with aircraft fires back home?) so usually had to refuel at Sohar.