This is obviously a first post, so please feel free to accept the following or otherwise at your discretion:
From a third hand source and based on an eye witness account, this is what is alledged to have occurred at Long Marston. The hunt supporter is said to have approached from the front of the aircraft after pulling up in his Land ( or Range) Rover with his wife at the fuelling bay. The pilot(s) who were confused by what was going on apparently shouted to the man to move as they were pulling away, he approached the front of the craft shouting back "you are going nowhere." Again it is said that the pilots were heard to shout to move as they were taxiing and again he apparently repeated "you're not going anywhere."
It is then believed that he approached and tripped over the rear wheels where the blade unfortunately struck his head, however he did momentarily stand up, albeit with a severe head wound before falling down backwards to the shock of all present including of course his wife.
As mentioned above, this is third hand and partially chinese whispers so please feel free to fill in the gaps however you feel or even totally disregard the above post as required.....