Original sentence: However, contemporary Allied carrier fighters such as the F6F Hellcat and F4U Corsair were considerably more robust and so more practical for carrier operations.Performance was greatly increased when later versions of the Seafire were fitted with the Griffon engines
Edited sentence: However, contemporary American carrier fighters such as the F6F Hellcat and F4U Corsair were considerably more robust and so more practical for carrier operations.Performance was greatly increased when later versions of the Seafire were fitted with the Griffon engines but could remained vastly outclassed by their American counterparts