ASRS 2274667

Reporter 1

I was VFR Flight training with a Student Pilot on board. Made numerous announcements in the pattern to our intentions on CTAF frequency. After turning base to final and descending on short final through 200' AGL, a Challenger jet announced he was departing Runway XX, and had crossed the hold short line stating they had an IFR clearance void time they did not want to miss. This provided an unsafe condition where it was impossible for us to land during his take off roll and we took evasive action and initiated a go-around and side- stepped to the right to avoid his wake turbulence and possible mid-air being unsure of which heading he was given to fly. This runway incursion and flagrant misuse of the excuse of "Clearance Void Time" could have easily caused a more serious mishap.

Reporter 2

At ZZZ, uncontrolled field, received IFR clearance through local ZZZ TRACON phone number. Initial climb to 4000'. Void time in 5 mins. There were multiple aircraft in the local patter. After a landing 172 that was on touch and go. Made appropriate calls (First Officer) to enter runway (rwy XX). There was an aircraft that was turning left base. A visual inspection of final was done with no aircraft and the touch and go aircraft just started upwind and continued straight out. Entered runway for takeoff. Delayed slightly to allow separation. Took off without issue. Was unaware of any other aircraft but was informed later that an aircraft had to side step and go around on landing XX. We did not have any TCAS, visual, or other warning. No close call on proximity to aircraft, however, lesson to learn is to triple check final and all pattern both visually and radio before departure.