Photos: Delta 4-Heavy rocket awaits liftoff from historic SLC-6 launch pad

A United Launch Alliance Delta 4-Heavy rocket is awaiting liftoff with a classified U.S. government spy satellite at Vandenberg Air Force Base’s historic Space Launch Complex-6, a picturesque rocket facility that was once intended to support launches of military astronauts and space shuttles.

These photos show the triple-body rocket, clad in orange thermal insulation, standing on the SLC-6 launch pad ahead of liftoff with a National Reconnaissance Office payload Monday, April 26. Liftoff is from the launch site on California’s Central Coast set for 1:46 p.m. PDT (4:46 p.m. EDT; 2046 GMT).

The 233-foot-tall (71-meter) Delta 4-Heavy launcher is one of four Delta 4s remaining in ULA’s inventory. All are assigned to carry top secret NRO spy satellites into orbit, with two scheduled from Vandenberg and another two set to take off from Cape Canaveral Space Force Station in Florida.

The Delta 4-Heavy is one of the most powerful rockets in the world, and the heaviest booster in ULA’s rocket family.

See our Mission Status Center for live coverage of the countdown and launch.

Credit: Brian Sandoval / Spaceflight Now
Credit: Brian Sandoval / Spaceflight Now
Credit: Brian Sandoval / Spaceflight Now
Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance

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