Narrative:

Located on FBO's ramp area; [we] contacted the control tower and requested a departure with an unrestricted climb with current ATIS information. Tower cleared me for the departure with the unrestricted climb. No mention of conflicting aircraft was mentioned by the tower and no conflicting arrivals or departures were heard on the radio. Approximately 1 minute later; I noticed an airplane at a strange altitude and location. No mention of traffic was made by control tower and no radio call was heard from the airplane. I resumed visual scanning of the airspace and saw the airplane approximately 100 ft to the right and in front at the same altitude on a collision course. I quickly pulled aft cyclic and made a rapid climb over the airplane while the conflicting airplane passed approximately 20 ft under the helicopter. I then leveled out from the rapid climb and noted an altitude of 2;000 ft MSL with a current altimeter setting. As an estimation; the near miss occurred at approximately 1;800 to 1;900 ft MSL just north of the main taxiway parallel to the runway at approximately midfield. No radio transmissions were made by the tower concerning the traffic and no radio calls by the airplane were heard. I believe the near miss occurred as a result of four factors. First; I did not hear any communication from the airplane traffic prior or during departure. Whether there was any communication at all is unknown. Second; the tower did not caution about the conflict and issued an unrestricted climb to cause the conflict. Whether the tower was aware of the conflict or whether the tower was in communication with the traffic at all is unknown and the workload at the time may have not allowed the tower to issue the flight advisory. Third; I failed to visually identify the conflict prior to the near miss; which could have created greater separation. Fourth; the airplane did not fly proper altitudes for the arrival that he/she was on; creating the near miss. One arrival has airplanes crossing midfield at 1;000 ft MSL; which I assume the airplane pilot was flying; the conflict would not have occurred; [because] at that altitude the airplane would have passed a safe distance under the helicopter flight.

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Original NASA ASRS Text

Title: A helicopter pilot reported a near miss with an airplane at about 1;700 FT during a VFR departure in JNU airspace with no ATC traffic reports or communications from the other aircraft.

Narrative: Located on FBO's ramp area; [we] contacted the Control Tower and requested a Departure with an unrestricted climb with current ATIS information. Tower cleared me for the departure with the unrestricted climb. No mention of conflicting aircraft was mentioned by the Tower and no conflicting arrivals or departures were heard on the radio. Approximately 1 minute later; I noticed an airplane at a strange altitude and location. No mention of traffic was made by Control Tower and no radio call was heard from the airplane. I resumed visual scanning of the airspace and saw the airplane approximately 100 FT to the right and in front at the same altitude on a collision course. I quickly pulled aft cyclic and made a rapid climb over the airplane while the conflicting airplane passed approximately 20 FT under the helicopter. I then leveled out from the rapid climb and noted an altitude of 2;000 FT MSL with a current altimeter setting. As an estimation; the near miss occurred at approximately 1;800 to 1;900 FT MSL just north of the main taxiway parallel to the runway at approximately midfield. No radio transmissions were made by the Tower concerning the traffic and no radio calls by the airplane were heard. I believe the near miss occurred as a result of four factors. First; I did not hear any communication from the airplane traffic prior or during departure. Whether there was any communication at all is unknown. Second; the Tower did not caution about the conflict and issued an unrestricted climb to cause the conflict. Whether the Tower was aware of the conflict or whether the Tower was in communication with the traffic at all is unknown and the workload at the time may have not allowed the Tower to issue the flight advisory. Third; I failed to visually identify the conflict prior to the near miss; which could have created greater separation. Fourth; the airplane did not fly proper altitudes for the arrival that he/she was on; creating the near miss. One arrival has airplanes crossing midfield at 1;000 FT MSL; which I assume the airplane pilot was flying; the conflict would not have occurred; [because] at that altitude the airplane would have passed a safe distance under the helicopter flight.

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.