SAN FRANCISCO — A United Launch Alliance Delta IV Heavy lifted a bus-sized classified satellite for the National Reconnaissance Office into orbit from Space Launch Complex-6 (SLC-6) at Vandenberg AFB, Calif., at 1:10 PST Jan. 20 — the largest rocket ever launched from the West Coast.
With a 63-ft.-long payload fairing, the launcher stood 235 ft. tall, weighed 1.5 million lb., and relied on the output from three Pratt & Whitney Rocketdyne RS-68 engines for first-stage lift. Called Common Core Boosters, the RS-68s are configured side-by-side, each producing 656,500 lb. of thrust.
The outer-two strap-ons provided the main first-stage lift. The combined first-stage thrust of nearly 2 million lb. is the most for any U.S. launcher since the Saturn V of the 1960s Apollo Moon mission era. The Delta’s second stage is a Pratt & Whitney Rocketdyne RL-10B-2 cryogenic engine.
Once designated as the West Coast space shuttle complex—an idea dropped after the 1986 Challenger accident—the $4 billion SLC-6 was refurbished at a cost of about $300 million to accommodate Delta IV missions.
The first came in November 2006 with a Delta IV Medium liftoff, but it relies on a single CBC for the first stage, a far cry from the thrust produced by three CBCs.
Called NROL-49, this latest NRO mission is the second for the Delta IV at Vandenberg and the only one yet scheduled for the Heavy configuration.
The four previous Delta IV Heavy launches have all been from Cape Canaveral AFS, Fla.