Pilot A was doing a Loop too close (over the runway) and too slow. His jet stalled out near the top of the loop and in the panic of the stall, he kept pulling the elevator. This lead to his jet staying in a stalled flight condition and heading across the runway and towards the pilots stations (far left station). Pilot B was flying his jet and his spotter saw Pilot A's jet coming at them and did his job grabbing his pilot to avoid being hit. Unfortunately Pilot A's jet hit the runway, skipped into the barrier and when the fuel hit the motor the mushroom ball was created, causing burns to the right side of Pilot B. Sadly Pilot B also lost his jet as during his scrambling as he lost his Tx and it crashed into the field straight ahead. The fire was put out and others on the flight line came to Pilot B's aid right away. I don't know the status of Pilot B but from others I talked to his right arm, leg and part of his face were burnt.
Just remember, spotters are NOT there to watch your (the pilot) flight, they are there to watch all the OTHER pilots flying. Glad Pilot B's spotter was doing his job!