Cessna 310/T310C
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Private
Flight Crew Last 90 Days 12; Flight Crew Total 2760; Flight Crew Type 2120
Other / Unknown
Conflict NMAC
General None Reported / Taken
Aircraft; Human Factors; Environment - Non Weather Related
After landing at BDU I received a radio call from a glider pilot. Though he wasn't sure I was the aircraft; he said we had a near miss; even though he said he did not see the other aircraft; he heard it and that I had passed about 100 FT beneath him. I never saw his aircraft. I had been keeping a lookout and watching for other aircraft on my G500 (TIS). I asked if he had a transponder; and he said no because he was a glider. If I was the aircraft that nearly collided with this glider; it was my responsibility to see and avoid him. That said; it is very difficult to spot gliders in the Boulder; CO; area due to terrain; size and flight characteristics. While this event has made me more aware of the potential conflicts with gliders in vicinity of the Boulder airport; and I intend to be even more vigilant in my visual scan; I would suggest that it would be even more helpful if the FAA encouraged gliders to carry transponders given the greater use of TCAS; TIS and ADS-B traffic alerting.
C310 pilot is informed after landing that he may have been involved in a NMAC with a glider. The glider pilot believes that the reporters aircraft passed 100 FT beneath him although he only heard the aircraft pass.