Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor
Flight Crew Last 90 Days 360; Flight Crew Total 18900; Flight Crew Type 1230
Conflict NMAC
Flight Crew Took Evasive Action
Airspace Structure
We were performing air work southeast of ZZZ in the 10;000 to 17;000 of altitude block. I had just given trainee nose high unusual attitude when we received traffic warning from ADS-B in/out avionics installed in aircraft. I looked out left side of aircraft (direction of traffic warning) observed airliner slightly below our altitude. I took control of aircraft and rolled wings level and began a climb to avoid airliner.
[Report narrative contained no additional information.]
L-39 flight crew reported a NMAC during unusual attitude training.