Narrative:

A glider that was operating at the uncontrolled field I was departing from had a faulty radio and flew a non-standard traffic pattern which caused him to fly over the top of me and land on the same runway as I was accelerating for take-off.while taxiing to runway xx at ZZZ; I heard a glider reporting its position entering downwind. I could not understand most of the transmission because his radio was cutting out every other word. I made a call telling him of this and he repeated the call which I mostly understood. I notified him that I got it that time and I visually identified him on downwind at what appeared to be pattern altitude. The gliders ground operator came on the radio and made two calls to the glider to extend so that the aircraft X could get out ahead of them. There was no response from the glider. At this point I was within approximately 500 ft. Of the runway and had finished the before takeoff check so I made the normal radio call of my intentions and continued to the hold short line and onto the runway for an immediate takeoff. As I accelerated through 35 kts; I saw a shadow pass by the right side of the aircraft and almost immediately saw the glider descending to the runway ahead of me. I aborted the takeoff and taxied back to the end of the runway for another takeoff. The ground crew came on the radio and apologized and also said they didn't know why the glider hadn't responded or why he had cut me off. After I returned to base; I called the glider club and talked to the president who hadn't been there but would find out who was flying and have them contact me. Within 15 minutes; I got a call from the pilot of the glider and we debriefed the incident from both perspectives. The president and the pilot both said that they would talk about this incident at the next club meeting. The glider's pilot stated that he did not hear any calls after the call that I made saying I had mostly understood his intentions. He said that he continued to make radio calls but these were not heard by me or anyone else due to his faulty radio. He was intending to make a short approach and a long landing to minimize his time on the runway and any delay to my departure. He turned his base leg at the numbers of the runway and stated that he saw me at the hold short line and that he thought I had stopped. After he leveled his wings on base he could no longer see me and from then on he had no visual contact with my aircraft due to his position in the pattern and where I was on the ground. He continued his approach and landing. He had no knowledge of what had happened until the ground crew told him when he was clear of the runway and out of the glider.the two main factors that led to this incident were a lack of communication due to a faulty radio in the glider; and a non-standard; (short approach); traffic pattern by the glider. The communication that I did have with the glider and my visual identification of his position in the pattern indicated to me that I had plenty of time to take off. Neither of us heard each other after the initial contact due to the gliders radio being faulty. The glider's nonstandard approach with a base turn direct to the numbers of the runway prevented me from seeing him as I took the runway because he was coming from behind and above me. After he leveled his wings on base he could no longer see what was happening at the departure end of the runway and he assumed that I had stopped and was waiting for him to land.

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Original NASA ASRS Text

Title: Pilatus PC-12/45 Pilot reported a critical ground contact event during takeoff roll with landing glider executing a non-standard approach with faulty radios.

Narrative: A glider that was operating at the uncontrolled field I was departing from had a faulty radio and flew a non-standard traffic pattern which caused him to fly over the top of me and land on the same runway as I was accelerating for take-off.While taxiing to Runway XX at ZZZ; I heard a glider reporting its position entering downwind. I could not understand most of the transmission because his radio was cutting out every other word. I made a call telling him of this and he repeated the call which I mostly understood. I notified him that I got it that time and I visually identified him on downwind at what appeared to be pattern altitude. The gliders Ground Operator came on the radio and made two calls to the glider to extend so that the Aircraft X could get out ahead of them. There was no response from the glider. At this point I was within approximately 500 ft. of the runway and had finished the before takeoff check so I made the normal radio call of my intentions and continued to the hold short line and onto the runway for an immediate takeoff. As I accelerated through 35 kts; I saw a shadow pass by the right side of the aircraft and almost immediately saw the glider descending to the runway ahead of me. I aborted the takeoff and taxied back to the end of the runway for another takeoff. The ground crew came on the radio and apologized and also said they didn't know why the glider hadn't responded or why he had cut me off. After I returned to base; I called the glider club and talked to the President who hadn't been there but would find out who was flying and have them contact me. Within 15 minutes; I got a call from the Pilot of the glider and we debriefed the incident from both perspectives. The President and the Pilot both said that they would talk about this incident at the next club meeting. The glider's pilot stated that he did not hear any calls after the call that I made saying I had mostly understood his intentions. He said that he continued to make radio calls but these were not heard by me or anyone else due to his faulty radio. He was intending to make a short approach and a long landing to minimize his time on the runway and any delay to my departure. He turned his base leg at the numbers of the runway and stated that he saw me at the hold short line and that he thought I had stopped. After he leveled his wings on base he could no longer see me and from then on he had no visual contact with my aircraft due to his position in the pattern and where I was on the ground. He continued his approach and landing. He had no knowledge of what had happened until the ground crew told him when he was clear of the runway and out of the glider.The two main factors that led to this incident were a lack of communication due to a faulty radio in the glider; and a non-standard; (short approach); traffic pattern by the glider. The communication that I did have with the glider and my visual ID of his position in the pattern indicated to me that I had plenty of time to take off. Neither of us heard each other after the initial contact due to the gliders radio being faulty. The glider's nonstandard approach with a base turn direct to the numbers of the runway prevented me from seeing him as I took the runway because he was coming from behind and above me. After he leveled his wings on base he could no longer see what was happening at the departure end of the runway and he assumed that I had stopped and was waiting for him to land.

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.