The "Lightning F.6" was the ultimate Lightning version to see British service. Originally it was nearly identical to the F.3A with the exception that it could carry two ferry tanks on pylons over the wings. These tanks were jettisonable in an emergency, and gave the F.6 a substantially improved deployment capability. There remained one glaring shortcoming: the lack of cannon. This was finally rectified in the form of a modified ventral tank with two ADEN cannons mounted in the front. The addition of the cannons and their ammunition decreased the tank's fuel capacity from , but the cannon made the F.6 a "real fighter" again.