Bumblebee originally concentrated on a ramjet powered design, and the initial Applied Physics Lab PTV-N-4 Cobra/BTV (Propulsion Test Vehicle/Burner Test Vehicle) was flown in October 1945. Cobra eventually emerged as the RIM-8 Talos, which entered service on 28 May 1958 aboard the light cruiser USS "Galveston". As part of the development program, several other vehicles were also developed. One of these developed into the RIM-2 Terrier, which entered operational status on 15 June 1956, two years before Talos; Terrier was first installed aboard the heavy cruiser USS "Canberra". The Terrier was later modified as a short-range missile system for smaller ships, entering service in 1963 as the RIM-24 Tartar. Together, the three missiles were known as the "3 T's".