Ceramite in its nature is a ceramic based material, while bieng resistant to heat, will still have a point of vaporization, and in that the nature of melta weapons (
http://wh40k.lexicanum.com/wiki/Melta_weapon ( Thank you Lexicanum ) ) is that of a
focused plasma beam. So in the end what you are saying is that a Stormbird could survive a direct collision with a star.
Plus the extra
D6 is only added at half range, so whatever gets within twelve inches of the vehicle fires and lets say rolls a 1 for a penetration roll, that or misses, whatever firepower you could bring to bear on it, is literally nothing compared to what you would be capable of on your next round of shooting. Seeing as a
BS of 4 and a lot of units carrying a "melta" weapon are definitely more fragile and definitely more slow ( tactical marine/ Fire Dragon with Fire Pike ) compared to the flyer.