What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
On August 22, 2018, Cessna N36LU, ^piloted by eric gussenhoven,^ was taking off from San Marcos Regional Airport (khyi) for a time-building flight. The pilot and passenger on board were both students from the local part 61 flight school.
N36LU conducted the engine runup and checklist at the ramp by the intersection of taxiways alpha, charlie, and delta. After the runup, N36LU proceeded to taxi to the intersection of runways 26 and 31 at taxiway delta. N36LU advised the tower of their position, holding short of runway 26 at delta, awaiting their IFR release. Tower replied back by instructing N36LU to hold short to wait for their release. At some point, another aircraft landed (the interview states this aircraft landed on runway 31 but it was never verified by ATC or the audio). N36LU was then cleared for takeoff for runway 26 at delta, with a heading clearance after departure. The PIC for N36LU replied back correctly and taxied to runway 31 instead of 26 and applied takeoff power.
Approximately forty four (44) seconds elapsed from N36LU'S readback clearance until khyi tower stated that N36LU was on the wrong runway and to abort. By that time, N36LU had just become airborne by the last 1,000 foot marker when the pilot complied with atc's abort instruction. The aircraft did not have sufficient runway left to stop and ended up running off the end of the runway. There were no injuries and only minor damages to the aircraft.
One of the last transmissions by ATC to N36LU before the recording ended was, "I should have let you keep going."
As the FAA filed it
ON AUGUST 22, 2018, CESSNA N36LU, ^PILOTED BY ERIC GUSSENHOVEN,^ WAS TAKING OFF FROM SAN MARCOS REGIONAL AIRPORT (KHYI) FOR A TIME-BUILDING FLIGHT. THE PILOT AND PASSENGER ON BOARD WERE BOTH STUDENTS FROM THE LOCAL PART 61 FLIGHT SCHOOL.
N36LU CONDUCTED THE ENGINE RUNUP AND CHECKLIST AT THE RAMP BY THE INTERSECTION OF TAXIWAYS ALPHA, CHARLIE, AND DELTA. AFTER THE RUNUP, N36LU PROCEEDED TO TAXI TO THE INTERSECTION OF RUNWAYS 26 AND 31 AT TAXIWAY DELTA. N36LU ADVISED THE TOWER OF THEIR POSITION, HOLDING SHORT OF RUNWAY 26 AT DELTA, AWAITING THEIR IFR RELEASE. TOWER REPLIED BACK BY INSTRUCTING N36LU TO HOLD SHORT TO WAIT FOR THEIR RELEASE. AT SOME POINT, ANOTHER AIRCRAFT LANDED (THE INTERVIEW STATES THIS AIRCRAFT LANDED ON RUNWAY 31 BUT IT WAS NEVER VERIFIED BY ATC OR THE AUDIO). N36LU WAS THEN CLEARED FOR TAKEOFF FOR RUNWAY 26 AT DELTA, WITH A HEADING CLEARANCE AFTER DEPARTURE. THE PIC FOR N36LU REPLIED BACK CORRECTLY AND TAXIED TO RUNWAY 31 INSTEAD OF 26 AND APPLIED TAKEOFF POWER.
APPROXIMATELY FORTY FOUR (44) SECONDS ELAPSED FROM N36LU'S READBACK CLEARANCE UNTIL KHYI TOWER STATED THAT N36LU WAS ON THE WRONG RUNWAY AND TO ABORT. BY THAT TIME, N36LU HAD JUST BECOME AIRBORNE BY THE LAST 1,000 FOOT MARKER WHEN THE PILOT COMPLIED WITH ATC'S ABORT INSTRUCTION. THE AIRCRAFT DID NOT HAVE SUFFICIENT RUNWAY LEFT TO STOP AND ENDED UP RUNNING OFF THE END OF THE RUNWAY. THERE WERE NO INJURIES AND ONLY MINOR DAMAGES TO THE AIRCRAFT.
ONE OF THE LAST TRANSMISSIONS BY ATC TO N36LU BEFORE THE RECORDING ENDED WAS, "I SHOULD HAVE LET YOU KEEP GOING."