Sail Plane
Flight Crew Commercial; Flight Crew Instrument; Flight Crew Glider
Flight Crew Last 90 Days 14; Flight Crew Total 491; Flight Crew Type 46
Communication Breakdown; Situational Awareness
Aircraft Equipment Problem Less Severe; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Took Evasive Action
Human Factors; Airspace Structure
I was PIC for a two-person glider turning in a thermal a few miles east of Bergseth Field in Enumclaw; Washington. I was flying with a CFI-Glider rated passenger; who was in the rear seat.We were required to quickly deviate from our altitude and intended course to vacate the flight path of a Boeing 767.My CFI-Glider rated passenger was on the controls climbing in a thermal and I was watching for traffic. When I saw the conflicting traffic I estimated that it was perhaps 2 miles away at 2 o'clock (going to 12 o'clock with our rapid clockwise turn rate); generally at our altitude of 7;000 feet.At [an estimated] 270 knots that means it may have been about 15 seconds of distance. It's unlikely we would have been able to see it on our prior turn; given that it was traveling at 4.5 NM per minute.The conflicting traffic did not appear to deviate from their course or altitude. We don't believe they ever saw us. We did keep turning to possibly get some lateral distance; but primarily dove away approximately 300 feet.We did not see the aircraft after making initial visual contact and turning/diving away; until it was well past us. We do not know how closely it approached by us.I fly powered aircraft IFR and was well aware of the CHINS ONE arrival in the area; so we discussed it while proceeding to the White River valley area. I determined the Approach Control frequency for the procedure on my mobile device; but the glider's radio was inoperative and we were unable to reach them on our handheld radios to receive VFR flight following services or at least alert ATC to our presence.We had noted other traffic flying the arrival route earlier and knew that it was active. We could have looked for better lift conditions elsewhere to avoid the situation with the traffic conflict. If our glider had been transponder equipped it would have led to a TCAS advisory and the situation also could have been avoided.
A glider pilot reported an airborne conflict with a B767 while climbing in a thermal southeast of Seattle-Tacoma; Washington.