cthia wrote:"And we shall christen this new SD design ..."
The Unfathomables
Do HV missiles incorporate a compensator? They do not have flesh that could turn into paste at enormous accelerations, so no compensator, right? (Although I have always questioned the durability of the hardware at such accelerations, I'll agree to hand wave that away), but what is limiting HV missiles, seemingly, to ~ .8C?
Honorverse missiles can reach 0.9c. Heck, from rest a RMN MDMs, like the Mk23, can reach 0.81c.
Even as far back as HotQ it talks about 0.9c missiles ballistic strikes (against non-maneuvering orbital targets). And those were single-drive missiles; which means their 'from rest' burnout velocity is only about 0.27c. So to make a 0.9c launch (using the Honorverse's inconsistently application of relativity) requires the launch ship to spend hours first working itself up to a velocity of 0.63c towards the target.
It's the warships that are limited (as others noted, by their particle screens) to 0.8c in n-space (and 0.6c in hyper).
That said, except in hyper, we just don't see Honorverse warships get anywhere near their max velocity -- even if the ship could pull 700g it'd still take it nearly 10 hours to work up to 0.8c - and would have covered 233 lightminutes (28 AU), by which point it's long since flown past anything of likely interest.