Narrative:

Aircraft X called unicom after engine startup and verified radio was working and received barometric pressure and reported runway winds. Pilot of aircraft X had observed over the previous hour to flight that other aircraft were taking off and departing runway xx. Aircraft X then reported taxiing from hangars to runway xx on CTAF. Aircraft X taxied past FBO noting several aircraft on ramp along with what later turned out to be aircraft 2. Aircraft X performed run-up in designated run-up area near the threshold for runway xx. While taxiing up to threshold for departure; pilot of aircraft X heard very broken communication from citation with unicom. Aircraft X announced on CTAF that they were departing runway xx with a downwind departure from the pattern. Aircraft X heard no other communication from aircraft Y. On initial liftoff; aircraft X saw aircraft Y roll onto runway xy and proceeded to depart runways. Aircraft X took evasive action banking to the right while climbing but staying below pattern altitude as [runway] xx is right-hand traffic. After stabilizing the aircraft from the maneuver aircraft X called aircraft Y to determine if they were able to hear aircraft X. There was no response from aircraft Y. Aircraft X then called unicom on the same frequency to see if they could be heard and received a 5 x 5 report back. Later during the short flight in vicinity; aircraft X also called out to another aircraft who was departing ZZZ to see if the radio was working properly and received a 5 x 5 report back. Later pilot of aircraft X visited FBO where aircraft Y taxied from to discuss what had happened. Pilot of aircraft X learned that aircraft Y taxied from the ramp directly to runway xy and departed without stopping.

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Original NASA ASRS Text

Title: Decathlon pilot reported a near mid-air collision during takeoff with an opposite direction Citation that was not communicating on CTAF.

Narrative: Aircraft X called UNICOM after engine startup and verified radio was working and received barometric pressure and reported runway winds. Pilot of Aircraft X had observed over the previous hour to flight that other aircraft were taking off and departing Runway XX. Aircraft X then reported taxiing from hangars to Runway XX on CTAF. Aircraft X taxied past FBO noting several aircraft on ramp along with what later turned out to be aircraft 2. Aircraft X performed run-up in designated run-up area near the threshold for Runway XX. While taxiing up to threshold for departure; pilot of Aircraft X heard very broken communication from Citation with UNICOM. Aircraft X announced on CTAF that they were departing Runway XX with a downwind departure from the pattern. Aircraft X heard no other communication from Aircraft Y. On initial liftoff; Aircraft X saw Aircraft Y roll onto Runway XY and proceeded to depart runways. Aircraft X took evasive action banking to the right while climbing but staying below pattern altitude as [Runway] XX is right-hand traffic. After stabilizing the aircraft from the maneuver Aircraft X called Aircraft Y to determine if they were able to hear Aircraft X. There was no response from Aircraft Y. Aircraft X then called UNICOM on the same frequency to see if they could be heard and received a 5 x 5 report back. Later during the short flight in vicinity; Aircraft X also called out to another aircraft who was departing ZZZ to see if the radio was working properly and received a 5 x 5 report back. Later pilot of Aircraft X visited FBO where Aircraft Y taxied from to discuss what had happened. Pilot of Aircraft X learned that Aircraft Y taxied from the ramp directly to Runway XY and departed without stopping.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.