Flight Crew Flight Instructor; Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 160; Flight Crew Total 12000; Flight Crew Type 500
Situational Awareness
Aircraft Equipment Problem Less Severe; Conflict NMAC
Flight Crew Took Evasive Action; General Maintenance Action
Aircraft; Human Factors
[I was] flying a practice GPS approach to Runway 18 at L18. [I] heard a Cessna 172 aircraft in pattern. Pilot was announcing position on CTAF; but not every leg of the pattern. I was proceeding straight in and announced my position at 10; 5; 3; and 1 miles relative to a straight in final. Was looking for the C172 but did not have them visually. I picked up relative movement in my peripheral vision and saw the C172 in the turn from left base to final at my altitude. They were about 200 FT in front of me but my speed was 90 KTS; much faster than their speed. As we were both descending I made a hard right climbing turn to avoid contact. As I climbed out I called to ask if they had in fact been broadcasting their position the whole time while in the pattern. No response. Upon further investigation it appears that my #1 comm radio; which was in use at the time; is cutting out after I transmit. It returns to normal after several seconds. This transmit problem seems to be happening intermittently therefore make it difficult to diagnose. I have service scheduled for this unit.
GA7 pilot reports a NMAC at L18 during a practice GPS approach to Runway 18. A C172 was heard in the pattern on CTAF but was apparently not announcing each leg so the reporter was not aware of his position until coming into very close proximity. It turns out the reporter's radio was malfunctioning.