I have absolutely no idea what's wrong with my grammer, but I'm technically correct... the F-57B *isn't* the two person Sabre.
Ah. My apologies, in that case you are indeed right
.
As for the Rapier's, I don't think there's any reason to believe that they're some special new H variant... they're probably just the C model of the Rapier (plus, isn't 'H' a special designator for actual aircraft?)
Well, no. It depends on the placing in the designation. If it's after the number (in this case, 44), it simply means the next "major modification" of the design. Thus, H means the next variant after G. In this sequence, only two letters are skipped - I and O, presumably because they could be confused for numbers.
Now, the reason why I suggested that he meant the F-44H goes like this. He calls the Rapier an F-54D. The trouble with this, is that F-54 is the Epee, not the Rapier. The last variant of the Epee we saw was the F-54C. Thus, if he called the Rapier F-54D, he meant that it's the next variant after the one in the game (F-44G). So, if we use the proper F-44G instead of F-54C, and move on to the next variant, it would be F-44H.
And yes, if the H was placed before or immediately after the F (eg. HF-44 or FH-44), then it would be a special designation. FH-44 would be a helicopter, whereas HF-44 would be a fighter specially modified for rescue work. Of course, that's according to the current (1962) American system.