Date: 201201
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Helicopter
Operator: FBO
Operating under: Part 91
Flight plan: None
Mission: Training
Flight phase: Landing
Airspace: Class G ZZZ
ATC / advisory: CTAF ZZZ
Second aircraft: Cessna 150
Aircraft component: VHF
Component problem: Malfunctioning
Reporter organization: FBO
Reporter function: Instructor; Pilot Flying
Reporter qualification: Flight Crew Commercial; Flight Crew Flight Instructor; Flight Crew Instrument
Human factors: Communication Breakdown; Confusion; Physiological - Other; Situational Awareness
Anomaly: Aircraft Equipment Problem Critical; Conflict Airborne Conflict
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Took Evasive Action; General Maintenance Action
Contributing factors: Environment - Non Weather Related; Aircraft
Primary problem: Aircraft

Narrative: I was doing flight instruction coming back from doing off-airport training. Winds were calm; visibility was unlimited; sky was clear; [and the] sun was starting to set. Throughout the day; I observed fixed wing traffic using both Runway 30 and 12 for takeoff and landing as the winds were calm. I was making radio calls to enter a 45 for extended left base for Runway 12 about 4 miles out. During my approach to left base; I did not hear any aircraft make any radio calls for takeoff; I did see one airplane depart Runway 30 about three miles ahead during my approach to left base. He was departing the area to the northwest; he was no factor. I was at 500 FT AGL; started on my left base and descent for parallel Taxiway 12; made my radio call (Airport Traffic; Helicopter; is on a left base for parallel Taxiway 12; airport traffic.) Before turning; I cleared the area to the right; forward; and when I looked to the left; the airplane was airborne and in a climb headed in my direction; I immediately banked left to avoid what might have been a collision and made right traffic for parallel 30 and landed upon arrival to the parking area. The fixed wing pilot parked also and said I was not talking on the radio; which I was the whole flight. Upon further inspection of my radio after the flight; I discovered that the coaxial cable that runs the radio antenna had disconnected from the radio during flight which is why I was not transmitting during my radio transmissions during various stages of the flight around the airport. The closest distance to the airplane at any given time during the incident was no more than 500 FT. Contributing factors included: Glare on the windscreen as the sun was at its lowest point on the horizon limiting visibility on left base; aircraft using both runways for take off and landing; and an unknowingly disconnected and non-transmitting radio. Corrective actions: upon aircraft sighting; turned to remain clear of fixed wing flow. Adjusted and secured radio coaxial cable to avoid any future in-flight radio disconnection.




Synopsis: A helicopter pilot took evasive action from an aircraft departing a CTAF airport and thought the other pilot was not making position reports in response to his but after landing discovered his radio not connected to its antenna.