Viper could be lighter. Carbon mast to reduce weight aloft, carbon hulls and beams also to reduce weight.
You forgot to mention why the Viper is basically over weight, its not the mast nor the hulls which is the real concern. AHPC choose for commercial economy ( cost to the bottom line on the balance sheet )to use the beams rudders and all ancillaries from its bigger sister the F18 and by design choice, to have larger bouyancy ( big hulls )than the other F16's.
If dedicated F16 suitable components had been used then it would be similar in weight to most of the earlier generation designs ie around 115 - 120 kilos.
The Viper is an interesting boat and must be being looked at by many of the lighter F18 crews, it already seems on a par performace wise with the F18's, has a better handicap and best of all, can be beach handled with ease by two crew.
