In Australia the Blackhawks used to be able to be flown single pilot/two crew ie: (single pilot with competent person in left seat) but after a couple of accidents they are flown only dual pilot now, I have about 60-70 hrs left seat in Blackhawk as all the test flying used to be done with a Pilot right seat and Technician in left seat (me!!!). but those days are over its been dual pilot since about 1995, I used to be able to do APU runs and engine runs with rotor brake on but once again those days are gone ,only pilots can run APU's and Engines on Australian Blackhawks now.