Narrative:

The PIC (non-flying) pilot for the leg was on board the running helicopter so we could cool the interior for a passenger leg; I (sic-flying) had just escorted the passenger to the awaiting aircraft for the trip. I strapped into the helicopter and proceeded to do the final checklist items prior to take off from a non-movement area when the PIC called ready for takeoff. The controller told us to proceed to the intersection V/B in the movement area; however we thought it safer to depart from the non-movement area due to personnel and equipment between us and the intersection. The PIC asked for an amended clearance and told them that we would not 'hit anything' on our departure; [but we were] told to standby. During this period; several aircraft were also receiving ATC instructions on the frequency as several [aircraft were] departing at close intervals. Through the radio chatter; over the intercom the PIC told me we were cleared to go; I queried him and said 'I didn't hear them tell us departure from the non-movement area is at our own risk; cleared for take-off' and his reply was 'you won't hear that here'! At his insistence; I proceeded with the take-off; flying a direct course to [our destination]. He immediately contacted departure control with our altitude and on course heading which was met with 'who is checking in'; I knew then we had taken off without a clearance. After some initial vectoring we were cleared on course and prior to the hand off were told of the possible deviation and given a number to call.I should have insisted on clarification; however was hesitant due to his experience and my relatively low time against the demeanor of the captain and the need to meet our passenger's itinerary. Our normal protocol is everyone should be clear on ATC instructions however this one fell through the cracks.

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Original NASA ASRS Text

Title: Helicopter flight crew reported taking off without clearance due to communication confusion in the cockpit.

Narrative: The PIC (non-flying) pilot for the leg was on board the running helicopter so we could cool the interior for a passenger leg; I (SIC-flying) had just escorted the passenger to the awaiting aircraft for the trip. I strapped into the helicopter and proceeded to do the final checklist items prior to take off from a non-movement area when the PIC called ready for takeoff. The controller told us to proceed to the intersection V/B in the movement area; however we thought it safer to depart from the non-movement area due to personnel and equipment between us and the intersection. The PIC asked for an amended clearance and told them that we would not 'hit anything' on our departure; [but we were] told to standby. During this period; several aircraft were also receiving ATC instructions on the frequency as several [aircraft were] departing at close intervals. Through the radio chatter; over the intercom the PIC told me we were cleared to go; I queried him and said 'I didn't hear them tell us departure from the non-movement area is at our own risk; cleared for take-off' and his reply was 'you won't hear that here'! At his insistence; I proceeded with the take-off; flying a direct course to [our destination]. He immediately contacted departure control with our altitude and on course heading which was met with 'who is checking in'; I knew then we had taken off without a clearance. After some initial vectoring we were cleared on course and prior to the hand off were told of the possible deviation and given a number to call.I should have insisted on clarification; however was hesitant due to his experience and my relatively low time against the demeanor of the Captain and the need to meet our passenger's itinerary. Our normal protocol is everyone should be clear on ATC instructions however this one fell through the cracks.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.