Narrative:

We were notified that another helicopter was also dispatched to same scene. Five minutes into the flight we were notified that the other helicopter would be delayed at the hospital helipad due to intubation of patient so we were to land at a secondary landing zone 1/2 mile away. Upon arrival I made radio calls on both CTAF and the helicopter air-to-air frequencies with no response. I then overflew the hospital helipad at 800 feet AGL and confirmed that they were still on the helipad. I turned from a right hand base to final and announced intentions to land. Within 1 minute of my landing call the other helicopter announced departing hospital helipad on lifeguard status to the northwest. I called to the lifeguard helicopter and told the pilot his course was crossing my final course to landing and his statement to me was that; 'he would just go over the top of us.' this takeoff was a downwind departure that caused the helicopter to overfly us on final by approximately 100 to 150 feet; then depart the area to the southeast. I was on short final to the helipad and was committed to the landing due to large trees surrounding the landing zone and the other helicopter overflying our helicopter causing me to have no option for a go around. As a result; I took out applied power and descended into landing zone completing the landing with no further incident. I feel this incident was rushed due to having a patient on board the lifeguard aircraft which could have lead to a catastrophic outcome and I credit my crew for great situational awareness and helping to acquire the approaching aircraft.

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Original NASA ASRS Text

Title: Two EMS helicopters working the same incident experience a NMAC while simultaneously landing and departing from adjacent landing zones.

Narrative: We were notified that another helicopter was also dispatched to same scene. Five minutes into the flight we were notified that the other helicopter would be delayed at the hospital helipad due to intubation of patient so we were to land at a secondary landing zone 1/2 mile away. Upon arrival I made radio calls on both CTAF and the helicopter Air-to-Air frequencies with no response. I then overflew the hospital helipad at 800 feet AGL and confirmed that they were still on the helipad. I turned from a right hand base to final and announced intentions to land. Within 1 minute of my landing call the other helicopter announced departing hospital helipad on lifeguard status to the Northwest. I called to the lifeguard helicopter and told the pilot his course was crossing my final course to landing and his statement to me was that; 'he would just go over the top of us.' This takeoff was a downwind departure that caused the helicopter to overfly us on final by approximately 100 to 150 feet; then depart the area to the southeast. I was on short final to the helipad and was committed to the landing due to large trees surrounding the landing zone and the other helicopter overflying our helicopter causing me to have no option for a go around. As a result; I took out applied power and descended into landing zone completing the landing with no further incident. I feel this incident was rushed due to having a patient on board the lifeguard aircraft which could have lead to a catastrophic outcome and I credit my crew for great situational awareness and helping to acquire the approaching aircraft.

Data retrieved from NASA's ASRS site as of April 2012 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.