Delta IV Heavy Launches in California

The second Delta IV Heavy lifts off from Vandenberg Air Force Base on Aug. 28. (Photo: United Launch Alliance, LLC)

The world’s most powerful rocket — the triple-barreled hydrogen-fueled Delta IV Heavy — launched into the California sky from Vandenberg Air Force Base Wednesday morning, Aug. 28, carrying a national security payload.

It was the second Delta IV Heavy launch from Vandenberg. The first was in January 2011.

From Vandenberg, Ray Johnson, vice president of Space Launch Operations, issued the following statement: “I’m very pleased to announce the successful launch of the Delta IV Heavy and its NROL-65 satellite. The vehicle lifted off of SLC-6 at Vandenberg Air Force Base at 11:03 PDT this morning. After working several issues during a challenging countdown, the vehicle flew with no anomalies. This mission includes the reentry of its second stage, which was also just completed. I want to congratulate the Delta and NROL team on this very successful and important launch.”

At the Aerospace El Segundo campus, a dozen employees waited on the top floor of the parking structure for a view of the huge rocket as it sped south along the California coast minutes after liftoff. One employee, equipped with a pair of powerful bird-watching binoculars, was able to see the two outside common booster cores peel away at just over four minutes into the flight.

Under a new liftoff strategy used for the first time, the Delta IV’s three engines ignited in a staggered sequence, with the starboard engine starting at T-minus seven seconds and the the port and center engines igniting at T-minus five seconds. The idea behind the staggered ignition is to reduce the dramatic fireball that occurs around the base of a Delta IV when unburned hydrogen leaks through the engine and hits burnoff sparklers. When the first Delta IV Heavy took off from Vandenberg, the fireball set fire to foam insulation on the outside of the common booster cores. The fire extinguished itself within seconds and everything proceeded without further incident. However, the spectacular flames startled observers and one Aerospace executive later commented, “I thought we had lost the mission.”

—Lindsay Chaney