(Vandenberg Air Force Base, Calif., Dec. 18, 2018) – The launch of a United Launch Alliance Delta IV Heavy carrying the NROL-71 payload for the National Reconnaissance Office was scrubbed today due to high ground winds.
The next launch attempt is planned for Wed., Dec. 19, from Space Launch Complex 6 at Vandenberg Air Force Base, Calif. The forecast indicates an 80 percent chance of favorable weather conditions for launch. The targeted launch time is 5:44 p.m. PST.
10:35 a.m. PST (1:35 p.m. EST; 1835 UTC)
Launch officials continue to monitor strong ground winds at Vandenberg. They are receiving periodic updates from meteorologists on the current and forecast conditions. Tower retraction remains on hold at this time.
Countdown clocks have been initiated at Vandenberg for today’s Delta IV Heavy launch. Weather permitting, we are just eight-and-a-half hours away from liftoff of the triple-core rocket on a vital mission for U.S. national security.
The application of power to the avionics aboard the Delta IV Heavy rocket is beginning at the start of the countdown. The equipment will be powered up for launch day testing and final preparations for fueling operations.
9:07 a.m. PST (12:07 p.m. EST; 1707 UTC)
From Vandenberg Air Force Base in California, this is Delta Launch Control at T-minus 8 hours and holding.
The countdown activities are about to begin for today’s liftoff of the United Launch Alliance Delta IV Heavy rocket on the NROL-71 mission for the National Reconnaissance Office.
Launch is scheduled for 5:57 p.m. PST (8:57 p.m. EST; 0157 UTC) from Space Launch Complex 6 on the southern end of Vandenberg.
The countdown will start at 9:27 a.m. PST from the T-minus 8 hour mark. Two pre-planned, 15-minute built-in holds scheduled in the count. One pause is reserved prior to fueling at T-minus 4 hours, 15 minutes, the other occurs prior to the terminal count at T-minus 4 minutes.
Rollback of the Mobile Service Tower is on hold this morning due to high ground winds forecast for the rest of the day while the vehicle stands exposed on the pad.
Dec. 17 -- LRR completed
The Launch Readiness Review at Vandenberg Air Force Base in California today culminated with officials giving a unanimous “go” for liftoff of the United Launch Alliance Delta IV Heavy rocket on the NROL-71 mission for the National Reconnaissance Office on Tuesday.
The launch is scheduled for 5:57 p.m. PST (8:57 p.m. EST; 0157 UTC).
“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.”
Weather forecasters from the Air Force’s 30th Weather Squadron predict gusty ground winds and a 20 percent chance of favorable conditions for the liftoff, with a few high-level clouds, northerly winds at 16 to 22 knots, gusting to 32 knots and a temperature near 60 degrees F. The only concern for a launch weather rule violation will be winds.
Crews at Space Launch Complex 6 today have retracted the 27-story Mobile Assembly Shelter away from the rocket. This 9-million-pound structure, which moves along rails, was built in the 1980s when the pad was being prepared for space shuttle launches. It was designed to shield the shuttle from the weather during on-pad assembly of the vehicle's solid rocket boosters, external tank and mating of the orbiter. Now, it gives calm working conditions during processing of the Delta IV.
On launch day, the pad’s other mobile structure will be rolled back. The 32-story, 13-million-pound Mobile Service Tower supports the work platforms that lower around the Delta IV Heavy and provide technicians complete access to the rocket, and supports vertical integration of the payload atop the launch vehicle.
United Launch Alliance will provide complete live coverage of Tuesday’s countdown in this blog starting at 9:00 a.m. PST (12 noon EST; 1700 UTC). Our Live Launch Updates Blog brings you official and timely information during the Delta IV Heavy rocket’s countdown with automatically-refreshing updates.
Our live video webcast also can be viewed on this page starting from L-20 minutes at 5:37 p.m. PST (8:37 p.m. EST; 0137 UTC).
At the request of our customer, live mission coverage will conclude after confirmation of payload fairing jettison, which is scheduled to occur about six minutes after liftoff.
Thursday, Dec. 13, 2018
(Vandenberg Air Force Base, Calif., Dec. 13, 2018) -- A United Launch Alliance Delta IV Heavy carrying the NROL-71 mission for the National Reconnaissance Office is set to launch on Tuesday, Dec. 18. The mission will lift off on a Delta IV Heavy launch vehicle from Space Launch Complex-6 at Vandenberg Air Force Base in California. The launch time is 5:57 p.m. PST.
(Vandenberg Air Force Base, Calif., Dec. 8, 2018) –The launch of a United Launch Alliance Delta IV Heavy carrying the NROL-71 mission for the National Reconnaissance Office was scrubbed today due to an unexpected condition during terminal count at approximately 7.5 seconds before liftoff. The team is currently reviewing all data and will determine the path forward. A new launch date will be provided when available.