I think there is possibly something slightly amiss with damage modelling. Yesterday during an online battle I managed to ignite the fuel tank of a player 109. He was burning, full on flames and smoke... leaving a huge trail of black smoke behind him. I thought that was it, he is shot down.. but nope. I chase him with no ammo to take screen shots. We chase around for ages, with him still fully on fire until he eventually shoots me down!
We spoke in game and he doesn't know how he was still alive also.
Here is a screenshot after being on flames for some time (5 mins or thereabouts).