A behemoth Delta IV Heavy rocket continues marching toward liftoff Friday night from Vandenberg Air Force Base, but the launch team is keeping a close eye on the weather.
The United Launch Alliance booster, which stands some 233 feet tall, will aim for departure at 8:19 p.m. from Space Launch Complex-6 on South Base.
Since the rocket will deliver cargo for the National Reconnaissance Office — the mission is dubbed NROL-71 — the actual launch window remains top secret, but is not expected to extend beyond 9:38 p.m.
“We are proud to launch this critical payload in support of our nation’s national security mission,” said Gary Wentz, ULA vice president of government and commercial programs. “As the nation’s premiere launch provider, the teams have worked diligently to ensure continued mission success, delivering our customer’s payloads to the precise orbits requested.”
“Team V has put in a lot of hard work for this launch,” said Col. Bob Reeves, 30th Space Wing vice commander. “We are dedicated to mission success and proud to work alongside United Launch Alliance and the National Reconnaissance Office.”
But weather may not cooperate. Forecasts have called for a 60-percent likelihood weather may interfere with blastoff plans, ULA representatives said.
If the launch slips 24 hours, conditions improve slightly for Saturday night, with a 40-percent likelihood of conditions stopping the countdown before liftoff.
On both days, the primary concern centers on ground winds expected to exceed limits, according to ULA.
Delta IV Heavy use three common booster cores strapped side by side to provide more capability for carrying the nation’s largest spy satellites into space.
Members of the 4th Space Launch Squadron focus on mission assurance while working with employees of ULA and others.
“Every mission is unique, and this Delta IV Heavy launch is a prime example of teamwork with a laser focus on mission success,” said Lt. Col. Kenneth Decker, 4th SLS commander and Air Force launch director for the mission. “Our mission assurance technicians and engineers have worked diligently with United Launch Alliance and the other mission partners to reduce risk in order to assure mission safety and security. The men and women of the 4 SLS are proud to contribute to this important mission.”
The booster will depart from the launch pad built for the West Coast space shuttle program, which was canceled before any blastoffs from that location.
Unlike many of the other launch pads at Vandenberg, SLC-6 is tucked into a coastal valley and not visible from the normal viewing sites around the Lompoc Valley. However, spectators are expected to gather at the the peak of Harris Grade Road and other locations around Lompoc to catch a glimpse of the rocket after it rises above the hills.
Due to safety reasons, Jalama Beach County Park will have a mandatory evacuation from 2:30 to 9 p.m. Friday. All campers will be relocated to the end of Jalama Road.
Coincidentally, a Friday night rocket launch could come after the Lompoc Valley Children’s Christmas Season Parade travels south on H Street. The procession with approximately 60 entries will start at 6 p.m. with the theme “Miracle on H Street.”
If the Delta IV Heavy departs, it will be the second launch of the week from Vandenberg, following Monday morning’s Falcon 9 blastoff with dozens of small satellites.