While the Regulus I patrols began, work was already underway on its replacement — the Regulus II. Concern that the Regulus I had too many vulnerabilities (speed, reliance on external guidance, time spent on the surface by the sub, etc.) led to Navy signing C-V to build a supersonic variant, one that would fly at 60,000 ft and Mach 2+. Following the model of the Regulus I program, C-V over-engineered the structural strength of the Reg II and started with most of the first production batch as recoverable drones. The Reg II would be guided by the (then) new inertial guidance system and would be launched from a new class of submarine, led by the Growler. First flight of the Reg II was barely 1 year after the Reg I went operational, May 1956 and on Sept 15, 1958 the first operational test launch took place off the Grayback. Control was picked up by the chase plane, a TV-2/T-33 and it headed towards its destination at Edwards AFB. Along the way, control was passed off to Pt. Mugu then finally Edwards itself. The flight was successful until the final moments after landing when it burst into flame after having to make a wheels up landing when the gea would not extend. By the endof the year a total of 48 successful flights had been accomplished including launches from a converted LST. In December 1958, however, inspite of the successful threshold the Reg II stood upon, Thomas Gates, SecNav, cancelled the program (a move ADM Zumwalt would later call one of the worst decisions he had seen). The reason was the Polaris SLBM program was stunningly successful and represented a quantum leap ahead in capability and survivability — the Reg II had been the ace-in-the-hole in case Polaris did not pan out. The Regulus finished its days as a target drone with the last of the program closing down in 1968. Despite the promise shown by the Regulus family, it would be decades later before the Navy was back in the cruise missile business again, this time with Harpoon and Tomahawk.
Fuselage Length: 386 in (9.8 m)
Wingspan: 252 in (6.4 m) extended, 118.5 in (3.0 m) folded
Wing Depth: 76 in (1.9 m)
Overall Height: 92.3 in (2.3 m)
Overall Length: 498.7 in (12.7 m)
Weight at launch: 13,685 lb (6,207 kg)