Narrative:

While hovering in the parking circle on the ramp just southwest of the hangar; my student and I had been cleared by tower for an RNAV departure from the ramp (this departure flies over the ramp parallel to runway xx before turning north-west to parallel runway xyr during the initial climb). We hovered out to the taxi line; did our before takeoff check; and started our ground run (maybe 1 minute between clearance and beginning the ground run). As we rotated for the climb - over the ramp about abeam taxiway xx - a helicopter crossed the ramp and runway xz/xx directly in front of us; at the same altitude; paralleling runway xyr. My student was on the controls and correctly flew a quick stop maneuver to avoid hitting the other helicopter. We were able to return to a hover and taxi back to the parking circle without further incident.I believe a lack of communication caused this situation. After we were cleared for the departure and before we started our ground run; I heard part of an exchange between tower and another helicopter I presume to be the aircraft we had to avoid. Due to communication with my student; I don't know what was said in that exchange; though I suspect it was a clearance to take off from the news helicopter's ramp by flying parallel to runway xyr. I didn't hear tower alert either us or the other helicopter that we would be in close proximity. If tower had alerted either of us; we could have coordinated so that we were not flying departures at the same time in the same place.

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Original NASA ASRS Text

Title: Helicopter instructor reported an NMAC during takeoff with another helicopter.

Narrative: While hovering in the parking circle on the ramp just southwest of the hangar; my student and I had been cleared by Tower for an RNAV departure from the ramp (this departure flies over the ramp parallel to Runway XX before turning north-west to parallel Runway XYR during the initial climb). We hovered out to the taxi line; did our before takeoff check; and started our ground run (maybe 1 minute between clearance and beginning the ground run). As we rotated for the climb - over the ramp about abeam Taxiway XX - a helicopter crossed the ramp and Runway XZ/XX directly in front of us; at the same altitude; paralleling Runway XYR. My student was on the controls and correctly flew a quick stop maneuver to avoid hitting the other helicopter. We were able to return to a hover and taxi back to the parking circle without further incident.I believe a lack of communication caused this situation. After we were cleared for the departure and before we started our ground run; I heard part of an exchange between Tower and another helicopter I presume to be the aircraft we had to avoid. Due to communication with my student; I don't know what was said in that exchange; though I suspect it was a clearance to take off from the news helicopter's ramp by flying parallel to Runway XYR. I didn't hear tower alert either us or the other helicopter that we would be in close proximity. If tower had alerted either of us; we could have coordinated so that we were not flying departures at the same time in the same place.

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.