Hmmm Black Arrow at 2 m wide is a tad larger than Polaris / Chevaline (1.37 m) but a little narrower than Poseidon (2.11 m). How about that... it would fit in the tubes of the 2nd generation of British SLBM launched in the 90's !
Compared to Polaris, Black Arrow is orbital (hence Mach 27) when Polaris is merely Mach 16. Second and third stages and orbital performance are not necessary for SLBM.
Hmmm... "British Black Arrow deterrent" comes to mind.
Black Arrow ICBMs, in silos
Black Arrow Skybolized, one carried by Vulcans
Black Arrow SLBM from submarines.
The irony being, the Black Arrow engines were derived from Blue Steel cruise missiles... and available from 1958 onwards. Shame they picked Convair & Atlas license to get Blue Streak, and all this for naught.
Now that would be something... "the peroxide submarine". AIP peroxide propulsion, peroxide torpedoes, and peroxide Black Arrow SLBMs.
If only H2O2 wasn't such a corrosive / explosive bastard stuff...
