What appeared to have happened was that the right front wheel shot up upon impact and entered the cockpit, striking the right frontal area of his helmet. The violence of the wheel's impact pushed his head back against the headrest, causing fatal skull fractures.[6] A piece of suspension attached to the wheel had partially penetrated his Bell M3 helmet and caused trauma to his head.[6] In addition, it appeared that a jagged piece of the upright assembly had penetrated the helmet visor just above his right eye.[6] Senna was using a medium sized (58 cm) M3 helmet with a new "thin" Bell visor. Any one of the three injuries would probably have killed him.[6]