3/4, 1/2 throttle on a boomerang? bah!
The boomerang is just a big glider with an optional engine in the front. When i got my wings i was messing around in it i pulled the throttle all the way back to idle put in full up elevator and with the headwind that i had at the time i stayed perfectly stationary. You could even do spirals to put in into a slow descent.
At my field we can fly any day of the week but we share it with different clubs. Unfortunately though during the week people like to come down on the weekdays for some really "relaxed" flying and don't bother to stick their radio tags in and generally do illegal flying. But my club is talking about getting a new field now with a main 200mx20m runway! It will almost be impossible to miss.
field:
http://www.wamasc.org.au/
club:
www.boomerangswa.org