It died too soon. That was the opinion of tag-end-of-Vietnam Chief of Naval Operations (i.e., top dog) Elmo Zumwalt. Zumwalt was noted not only for his unforgettable name, but also his “Z-Gram” messages to all hands, his many regulation changes (many of which would be reversed by successors), and, especially, blunt talk. Here’s what he said about the Navy’s 1964 cancellation of the Regulus missile, something that the Navy deployed on carriers, cruisers, and submarines, and that actually was the Navy’s first nuclear deterrent missile. It was the:
…single worst decision about weapons [the Navy] made during my years of service.
The Navy didn’t think it was that big a screwup, but Zumwalt was a big cruise missile fan, in many ways the father of the Tomahawk (which seems to be on its way out of submarine service, as the four remaining cruise missile SSGNs are all scheduled for scrapping. But that’s another post).
Regulus, though, was never anything but a stopgap. A conceptual child of the German Fieseler Fi103 V1 “buzz bomb,” it was an unmanned airplane that could be dismantled, stuffed into a cylindrical “hangar” atop a modified sub, and in the event of The Big One, the sub could surface, sailors could quickly assemble and arm the Regulus, and it would fire from a zero-length launcher and travel a preprogrammed course to a predetermined destination — over a Soviet target, where it would detonate its nuclear warhead.
Regulus was an aerodynamic oddity, with swept wings and vertical fin, but no horizontal tail at all, relying in part of the prewar and wartime work of Prof. Alexander Lippisch, who created the German Me163 rocket fighter. (The US was working its way through this “found technology” in the 1950s; Lippisch took American citizenship in this period). The robot jet had a single turbojet engine with its intake in the nose. The missile, which was first launched from a sub in 1953, resembled a period fighter aircraft, but the absence of any provision for a pilot or for landing gear made it lighter and more streamlined. (Although some test missiles carried a parachute as a means of recovering the missile, and the data it carried, operational missiles dispensed with that).
The Regulus had huge conceptual problems. For one thing, the sub was exposed, wallowing on the surface as the crew assembled and prepared it. For another, subs had a total offensive punch of one or two missiles, that’s it. Here’s the description from a Navy historical report:
The hangar could accommodate two Regulus I missiles in a rotating ring arrangement. The weapons could be checked out while the submarine was still submerged by entering the hangar through an access trunk, but actual launching required the submarine to surface and manhandle the weapon onto the rails before it could be fired. Then, the boat would have to remain at least at periscope depth to guide the missile to the radar horizon.
In addition, the targeting of the missile was fairly inflexible, requiring at least a launch boat and later, also, a boat near the target to come up to periscope depth, extend a radar mast, and radiate. If that wasn’t all, Regulus was basically a subsonic jet plane, and if we knew one thing from the fate of the V1 offensive, it was that manned airplanes guided by radar — something the Soviets had in great quantity — could hunt down unmanned airplanes rather well. In addition to their manned interceptors, the Soviets also constructed an anti-aircraft defense in depth which threatened bombers and Regulus-like cruise missiles alike (the Air Force was working on parallel programs at the time) with anti-aircraft artillery guided by fire-control and height-finding radar, and several interlocking types of anti-aircraft guided missiles.
Zumwalt wouldn’t like to hear it, but by 1964 his beloved Regulus was a dead duck. A Regulus II was designed to be faster (both faster to launch, and faster in the air) but it didn’t address the core problems.
In time, technology would allow all these problems to be answered with the Tomahawk Land Attack Missile and other cruise missiles. Subs could fire them from under the sea; their programming was rapidly changeable; they flew low, often below hostile radar, and many could be carried with much less hazard to the subs and surface combatants that launched them. It was still a subsonic jet plane, but the enemy would find it harder to find, hit and kill.
But in 1964, the weapon that had come on line and signed the decommissioning chit for Regulus was the Navy’s Polaris: the first submarine-launched ballistic missile. Polaris was a conceptual child of the V1’s Vergeltungswaffe stablemate, the V2 (Army A4) rocket. Unlike any subsonic airplane, in 1964 a re-entering ballistic missile was a target with no solution for enemy air defenses. But Polaris is another story.
And what happened to the subs that had huge hangars built on their decks for Regulus cruise missile? Well, they went to work for Navy Special Operations, and that, too, is another story.
Between 1953 and 1964, one cruiser and five converted fleet subs were equipped to launch Regulus. They were the nation’s only submarine nuclear deterrent until the George Washington class Polaris boats came on line. No Regulus was ever fired in anger, so you can argue they fulfilled their mission perfectly.
Within the last few years, the Navy has retroactively awarded the officers and sailors of the Regulus fleet the badge that recognizes today’s sailors for their patrols in missile boats. Nowadays, the Regulus I and its never-deployed descendant, the supersonic Regulus II, are only historical curiosities; transitional weapons studied by those interested in weapons technology, and in how weapons change history, and history changes them.