Yes the Alison turboprop on the Herk runs at 100% rpm at all times except when manually shifted to ground-idle mode (kids, do not try this inflight). Adding more fuel via more throttle = coarser prop pitch and more thrust (torque) but always at 100% rpm (prop low oil or pitch lock faults excepted of course!)
Fantastic throttle response gets you out of doo doo immediately with thrust and airflow increase over the top of the wing(limitation is no less than 1 sec. from idle to full throttle and be assured it will do it in 1 sec.)
One sweet engine and the sound is music to the ears. You fly it on constant TIT (turbine inlet temp) so starting out heavy your speed is lower and as you lighten up the speed increases. Interesting flight planning and a very interesting operation. A true pilot's engine and aircraft. Not for Atari Ferrari metrosexual pilots (you need 2 hands on the wheel, 2 feet working the rudder and oh yes you will have to trim elevators/rudder and ailerons and will need a third pilot/FE to keep the engines out of max limits or NTS.)
Last edited by Tree; 19th Apr 2008 at 05:05.