Robinson R22
Flight Crew Instrument; Flight Crew Commercial; Flight Crew Flight Instructor; Flight Crew Rotorcraft
Flight Crew Last 90 Days 65; Flight Crew Total 320; Flight Crew Type 270
Communication Breakdown; Situational Awareness
Deviation / Discrepancy - Procedural Clearance; Ground Incursion Runway
General None Reported / Taken
Human Factors
The helicopter has one radio with two intercom mods: 1) The hot mic; both occupants can freely talk and listen to the controller. However when one person is transmitting; the other can't hear what is transmitted.2) The PTT mic; for which the occupants have to press a button in order to talk to each other. However when one person is transmitting a radio call the other can hear the transmission.My student and I went for a flight with purpose to prepare him for his first solo. He was almost ready; so we agreed that he will do the radio communications today. We switched over to PTT mic for this initial call. On the ramp he called ground for taxi clearance. We were cleared to taxi and to hold short of the active Runway 19 at Bravo 3. The student had the controls and was taxiing to Bravo Taxiway and hold short of Runway 19. Also we switched intercom mode back to 'hot mic'. We were holding at Bravo at the approach end of Runway 1 due to traffic at the nearby Bravo runup area and additional traffic on the Bravo taxiway. At this time the airport was very busy and a lot of planes arrived for touch and goes. After holding short at Bravo for a bit; Ground called us to taxi and to hold short at Bravo 3. However my student understood that we were cleared to cross the runway expeditiously - which I did not hear because of the hot mic setup - and he accelerated the helicopter quickly forward. At this time I was focused on the departing traffic which just passed us and also the airplane turning base to final I didn't see any other traffic on the runway. I was bewildered that he went forward and was also checking with the student about if we really got the clearance to cross. At this time we were already about half way across the runway and ground control told us that we were not cleared to cross the runway. I took the controls immediately and finished crossing to the other side to Golf taxi way to get off the active runway as fast as possible. The ground controller informed us about a possible pilot deviation and we held short on Golf until we received the clearance to cross the Runway 19 back to the ramp. We decided to discontinue the flight. No further incidents occurred.
R22 Instructor reported a runway incursion after a miscommunication between the student pilot and the Controller.