A woman who watched as a Warwickshire Hunt supporter died in the propeller blades of a gyrocopter broke down as she recalled the moment in court.
Bryan Griffiths, 55, is charged with the manslaughter by gross negligence of Trevor Morse at Long Marston airfield on March 9 last year.
Birmingham Crown Court heard that Mr Morse, 48, had been trying to stop Griffiths, who had been monitoring the hunt from the air in his gyrocopter, from taking off after he stopped to refuel.
He refused to move out of the way as Griffiths went towards him and the rear propeller of the gyrocopter, moving at a speed approaching 200mph, cut his head from top to bottom, killing him instantly, the court heard.
Julie Sargeant, who had travelled to the airfield near Stratford-upon-Avon with Mr Morse, told the court she stayed inside the hunt's Land Rover because she "didn't want to get involved".
She said Mr Morse, a road monitor with the hunt, had followed the aircraft to the field to confront Griffiths, parking the Land Rover "right up to the nose" of the gyrocopter.
Miss Sargeant cried as she told the jury: "He (Mr Morse) went and stood in front of the gyrocopter, to the left hand side of it."
She told the court that she too had stood in front of the aircraft after she was beckoned out of the car by Mr Morse but she began to move away when the engine started. Mr Morse, however, stood fast, she said. "He was just stood there, he was just stood there," she told the court.
She added: "I can remember thinking, 'Oh right, they are going to start it.' Not at any point did I ever think there was any real danger.
"I just really wanted to go. I thought tempers might get a bit sore. It (the engine) started and then it moved forward and hit Trevor. I'm not aware of anything after that, other than trying to get an ambulance and someone to come to me."
Miss Sargeant, who described Mr Morse as "Mr Nice Guy", said the 15-minute wait for emergency services to reach the remote airfield "felt like an eternity".
Prosecutor Gareth Evans QC told the court: "The blade of the rear propeller cleaved Mr Morse's head from top to bottom. Mercifully death was instantaneous.
"The prosecution say that this man, the defendant, is criminally liable for this death. We say that he is guilty of manslaughter, we say that he caused Trevor Morse's death by his own gross negligence."
Griffiths, of Wiltshire Close, Bedworth, north Warwickshire, denies the charge.