Liftoff of the United Launch Alliance-made booster carrying a classified spy satellite payload for the National Reconnaissance Office is rescheduled for Sept. 13 some time during a period between 1:45 and 4:15 p.m. local PDT (4:45-7:15 p.m. EDT; 2045-2315 GMT).
The software issue during the Aug. 2 launch attempt hit Vandenberg's Mission Flight Control Center that computes radar, optical and telemetry data for safety specialists who track the rocket's path. The center has over 80 servers, eight operating systems and thousands of software processes, the Air Force says.
If a booster strays from its pre-set course, Range officials have the responsibility to destruct the rocket before it can threaten populated areas.
"Public safety is a huge part of our mission here at Vandenberg," said Col. Hook, 30th Space Wing Operations Group commander. "Our team worked hard to identify, test and restore the MFCC and we are excited to support a safe and successful launch Sept. 13."
In an interview Tuesday, Hook told a reporter from the local Santa Maria Times newspaper neighboring Vandenberg that the trouble was a "perfect storm" of timing that occurred as the countdown crossed 12 midnight. The team was performing a standard reinitialization of their computers to get into the final launch state while a background application in the control center was starting up at that exact time.
"It was during that process where we were reinitializing the computer that we recognized we had an issue because the screens did not come back up again," Hook said.
"This is related to the fact that this was spanning over the midnight hour. This application kicked off at midnight just as we were reinitializing the system. It was kind of a perfect storm of us reinitializing the system in addition to this background application that kicked off at midnight," Hook said. "If either one of those had occurred separately, it wouldn't have had an issue but it was the timing when they both occurred simultaneously that caused the problem."
Engineers have exhaustively tested out the system over the past several weeks at various hours of the day to gain confidence they understood the scenario that trigged the problem in the first place.
"Having sat through the past four weeks of analysis and testing, the team was extremely thorough in their analysis," Hook told the reporter. "We did testing at all hours of the day and night of both the simulator as well as the actual system. I am highly confident that we identified exactly what the cause was and that there is nothing else out that's similar that will cause this anomaly to occur again."
Payload requirements drive the launch time approximately 14 minutes earlier each passing day for the Atlas 5 to deliver the craft into the desired orbit. For the new Sept. 13 date, liftoff will occur in the mid-afternoon hours and avoid the countdown crossing midnight.
Originally scheduled for blastoff August 2 from America's western spaceport at Vandenberg Air Force Base, the launch known as NROL-36 was grounded due to technical troubles with the Range's Mission Flight Control Center. That vital facility processes radar, optical and telemetry data from various instrumentation sites and displays that information to the lead safety personnel responsible to monitoring the rocket's trajectory for public safety reasons.
After several weeks to troubleshoot, test and recertify the center, officials hope to launch the rocket on its clandestine mission to dispatch a payload for the National Reconnaissance Office the afternoon of Sept. 13.
Liftoff will occur some time during an unclassified period extending from 1:45 to 4:15 p.m. local PDT (4:45-7:15 p.m. EDT; 2045-2315 GMT). The exact launch time will be announced a few days in advance.
Once it became apparent the L-36 launch was facing a lengthy delay in early August, officials opted to let the NASA mission Cape Canaveral keep its appointed schedule. The Radiation Belt Storm Probes blasted off Aug. 30.
"The NROL-36 mission leadership has established a new launch date of Sept. 13 and a request for this new launch date on the Range has been submitted to the 30th Space Wing. The previously planned launch date of Sept. 6 was not available on the Range and mission managers have elected to revise the launch date to Sept. 13 as preferred for overall operational considerations," United Launch Alliance said in a statement.
The team established to work through the technical troubles that scrubbed the launch in early August is currently finalizing the implementation, test and certification of the corrective actions, ULA said.
Officials today announced Sept. 6 as the new target launch day for the NROL-36 mission.
The flight was scrubbed during the initial countdown Aug. 2 due to Range instrumentation troubles at Vandenberg. Engineers are on a path to resolution and hope to have corrective actions implemented, tested and certified by late August.
There are no issues being worked with either the Atlas 5 or the payload, officials said.
That puts the Aug. 23 launch of the Radiation Belt Storm Probes from Cape Canaveral next in the firing order. The rocket has been assembled and is scheduled to be topped by the tandem spacecraft on Thursday.
At Vandenberg Air Force Base, meanwhile, engineers continue their analysis and troubleshooting to understand a problem with the Western Range that cropped up late in the countdown on Aug. 2. The issue scrubbed the rocket's attempt to launch that day and the vehicle remains grounded awaiting a new liftoff date.
"During (the) countdown, Western Range Operations Control Center safety personnel identified an issue in the Mission Flight Control Center. The center processes radar, optical and telemetry data from instrumentation sites located on and off Vandenberg and displays and processes commands for the mission flight control officer, whose main responsibility is to terminate the flight of the launch vehicle should we need to for public safety reasons," the Air Force said in a statement to Spaceflight Now.
"Because public safety is the primary concern of the 30th Space Wing, we stopped countdown once the issue was identified."
Hoping the Range trouble would be fixed sooner rather than later, officials tentatively retargeted the launch for Aug. 14 or 15, the last opportunities to perform the California mission without impacting the Florida flight on Aug. 23.
The time necessary to complete the review of data from one launch before granting clearance to the next one requires about a week between missions.
But in meetings this week, the decision was made to stand down from the California launch for now and focus on getting the Aug. 23 flight performed for NASA.
"The Mission Flight Control Center is a complex and interdependent center comprised of 80 plus servers, 8 operating systems and thousands of software processes," the Air Force says.
The work to resolve the problem "will require in-depth engineering support to not only identify the cause of the malfunction but to correct, test and certify the center for operations."
Although the Vandenberg launch does not have a new launch date, the math says Aug. 30 would be the soonest it could occur, pending resolution with the Range.
Whenever that rocket does launch, it will carry a classified payload for the National Reconnaissance Office known as NROL-36.
"The launch of an Atlas 5 carrying the National Reconnaissance Office NROL-36 payload has been further delayed to no earlier than Tuesday, Aug. 14 to provide additional time for resolution of a Range instrumentation issue that developed during the initial launch attempt Aug. 2. There are no issues with the Atlas 5 vehicle or the NROL-36 space vehicle."
"The launch of an Atlas 5 carrying the National Reconnaissance Office NROL-36 payload has been delayed to Saturday, Aug. 4 to provide additional time for resolution of a Range instrumentation issue that developed during the initial launch attempt Aug. 2. There are no issues with the Atlas 5 vehicle or the NROL-36 space vehicle. The Aug. 4 launch will proceed pending resolution of the range instrumentation item and the launch window open time is 12:13 a.m. PDT. The forecast for Aug. 4 shows a 90 percent chance of favorable weather conditions for the launch."
The latest outlook calls for only a quarter-mile visibility, a solid marine layer from 100 feet extending to 1,000 feet, some high cirrus clouds at 25,000 feet, northerly winds of 5 to 10 knots and temperatures in the low 50s F.
"The launch of an Atlas 5 carrying the National Reconnaissance Office NROL-36 payload was scrubbed today due to a Range instrumentation issue. There are no issues with the Atlas 5 vehicle or the NROL-36 space vehicle and these systems are safe and secure. The launch is rescheduled for Friday, Aug. 3 from Space Launch Complex-3 at Vandenberg Air Force Base, Calif., pending resolution of the Range instrumentation system issue. The launch time for Aug. 3 is 12:27 a.m. PDT. The forecast for Aug. 3 shows a 90 percent chance of favorable weather conditions for the launch tomorrow."
All three cryogenic tanks are reported at flight level.
The stage is 41.5 feet in length and 10 feet it diameter. It also houses the navigation unit that serves as the rocket's guidance brain.
It is equipped with the RD-180 liquid-fueled main engine. This liquid oxygen/kerosene powerplant is a two-thrust chamber, two-nozzle engine.
As the CCB's name suggests, the stage is common and is used in all the various configurations of the Atlas 5 family. The booster stage is 106.6 feet long and 12.5 feet diameter.
Topped with the high-energy Centaur upper stage, Atlas rockets have been used since the 1960s to dispatch ground-breaking missions for NASA, including the Surveyors to the Moon, Mariner flights to Mars, Venus and Mercury, and the Pioneers that were the first to visit Jupiter and beyond.
In its newest era, the Atlas 5 rocket sent the Mars Reconnaissance Orbiter to the red planet in 2005, propelled the New Horizons probe toward Pluto and the solar system's outer fringes in 2006, doubled up with the dual Lunar Reconnaissance Orbiter and LCROSS impactor to the Moon in 2009, hurled Juno to Jupiter last August and dispatched the car-sized Curiosity rover on the Mars Science Lab mission in November.
Today marks the 32nd flight for Atlas 5, born of the Air Force's competition to develop next-generation Evolved Expendable Launch Vehicles. In its previous 31 missions since debuting in August 2002, the tally shows 10 flights dedicated to the Defense Department, 9 commercial missions with communications spacecraft, six with spy satellites for the National Reconnaissance Office and six for NASA.
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The liquid oxygen -- chilled to Minus-298 degrees F -- will be consumed during the launch by the Centaur's single RL10 engine along with liquid hydrogen to be loaded into the stage a little later in the countdown.
The Common Core Booster stage's liquid oxygen tank is the largest tank to be filled today. It holds about 50,000 gallons of cryogenic oxidizer for the RD-180 main engine.
Clocks have one more hold scheduled at T-minus 4 minutes. That pause will last 10 minutes during which time the final "go" for launch will be given.
All remains targeted for liftoff at the precise moment of 12:40 and 30 seconds a.m. local time (3:40:30 a.m. EDT; 0740:30 GMT) from Vandenberg Air Force Base, California.
Loading of cryogenic liquid oxygen and liquid hydrogen into the Atlas 5 rocket will be getting underway a short time from now.
This initial pause lasts 30 minutes, giving the team some margin in the countdown timeline to deal with technical issues or any work that is running behind. The final hold is scheduled to occur at T-minus 4 minutes.
Workers have left the pad area in advance of tonight's propellant loading and launch of the Atlas 5 rocket.
Today's launch will be the fifth Atlas 5 rocket to fly from Vandenberg's Space Launch Complex 3-East pad. The site underwent an extensive overhaul, with construction occurring in 2004 and 2005, to accommodate the larger and more powerful Atlas 5 family of rockets. Some of the major modifications included:
This is the 38th Atlas to fly from SLC 3 throughout Vandenberg history.
Today's mission will deliver to orbit a payload for the National Reconnaissance Office, the agency that operates the country's fleet of spy satellites. This is the fourth of four launches that the NRO has planned this year, a batch of missions that began in April with the Delta 4 from Vandenberg Air Force Base and continued with an Atlas 5 and a Delta 4-Heavy, both in June from Cape Canaveral.
"Last year we executed the most aggressive launch campaign in over 25 years. We successfully launched six satellites in seven months and this year with the same determination we're scheduled to launch four more in five months," Betty Sapp, now the NRO's director, said in testimony before Congress this spring.
"These successful launches are a very important and visible reminder of the space reconnaissance mission the NRO started over 50 years ago, and continues with such great success today. We are committed to smart acquisition investments and practices to ensure the continued coverage and availability of our vital national security systems and we work tirelessly to deliver these systems on time and within budget."
Last year's remarkable launch surge used various types of Atlas and Delta rockets to launch replacement satellites into virtually all of the NRO's networks of imaging, eavesdropping, surveillance and data-relay spacecraft, plus the small Minotaur booster lofted a research and development payload.
"From launching and operating the most technically-capable systems to continued operations of legacy satellites the NRO remains the premier space reconnaissance organization in the world," said Sapp.
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As the countdown gets started, the launch team will power up the rocket to conduct standard pre-flight tests and ready the vehicle for this national security satellite deployment mission.
Rollback of the mobile service tower from around the rocket is expected around 8:45 p.m. local. Once the gantry is removed, crews at the pad will make preparations to systems and equipment before the site is cleared of all personnel for fueling.
A planned 30-minute hold begins when the count reaches T-minus 120 minutes at 10 p.m. local time. With five minutes remaining in the hold, the team will be polled to verify all is in readiness to start loading propellant into the rocket for launch.
Supercold liquid oxygen begins flowing into the Centaur upper stage around 10:45 p.m. local, followed by the Atlas first stage. Liquid hydrogen fuel loading for Centaur will be completed a short time later.
A final hold is scheduled at 12:26 a.m. when clocks hit the T-minus 4 minute mark. That will give the team a chance to finish any late work and assess the status of the rocket, payload, Range and weather before proceeding into the last moments of the countdown.
Liftoff remains targeted for 12:40 a.m. local time (3:40 a.m. EDT; 0740 GMT).
The latest weather forecast is predicting even foggier conditions at launch time, with only a quarter-mile visibility, a solid marine layer at ground-level extending to 600 feet, some high cirrus clouds at 25,000 feet, northwesterly winds of 5 to 10 knots and temperatures in the low 50s F.
At this hour, photographers are out at the launch pad setting up their sound-activated cameras around the complex to capture blastoff, visibility permitting!
Managers gathered for the formal assessment of the hardware, state of pre-launch processing, support network and weather forecast before giving the consensus to enter into the countdown Wednesday afternoon.
Liftoff of the Atlas rocket from Vandenberg Air Force Base is targeted for 12:40 a.m. local (3:40 a.m. EDT; 0740 GMT).
The launch weather outlook predicts a 90 percent chance of acceptable conditions, but the marine layer and patchy fog along the coast and low-lying areas could hamper the view for spectators. The only slight concern for violating launch constraints is cumulus cloud development.
The latest prediction for launch time includes overcast conditions at 200 feet and tops at 800 feet, a few high cirrus clouds at 25,000 feet, a half-mile visibility, northwesterly winds of 5 to 10 knots and a temperature in the low 50s F.
This flight builds on the legacy of the Atlas vehicle's 401 configuration, which has flown a dozen times in the past decade with the combination of a four-meter payload fairing, no solid rocket boosters and a single-engine Centaur upper stage.
Depending on a payload's weight and desired orbit, mission planners add strap-on solid boosters to the United Launch Alliance-made rocket to incrementally increase the vehicle's performance.
But this cargo, a hush-hush cargo for the NRO known only as the NROL-36 mission, is satisfied with the lifting power of the basic Atlas 5 design.
The vehicle will fly south-southeastward away from Vandenberg, according to the notice to mariners issued today to warn the public of the impending rocket flight over the Pacific. Details about the ascent, its duration and the number of Centaur fairings are not revealed given the secretive payload, which appears to be targeting an orbital inclination tilted 63 degrees to the equator based on the flight path in the NOTAMs.
The Russian RD-180 first stage main engine will ignite at T-minus 2.7 seconds, roaring to full power while undergoing a check to ensure its vital signs are healthy.
Rising off the pad in a slow, majestic fashion, the 19-story Atlas vehicle will deliver nearly a million pounds of ground-shaking thrust for the middle-of-the-night departure.
Information about the launch will be available though the first stage of flight, initial ignition of the Centaur and jettison of the nose cone about five minutes after liftoff. At that point, the mission will go into the now-standard news blackout for NRO launches.
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Vandenberg's trademark marine layer is expected to be in place throughout the launch countdown. There is just a slight 10 percent chance for cumulus clouds from weather to the east that could violate any of the launch weather rules.
At launch time, the outlook calls for overcast stratus clouds at 200 feet with tops at 1,200 feet, some thin high cirrus clouds at 25,000 feet, only a half-mile of visibility with fog, northwesterly winds of 10 to 15 knots and a temperature in the mid 50s F.
If the launch should slip to Friday for some reason, similar weather is expected again.
The exact duration of the daily launch window hasn't been disclosed. But officials previously said the liftoff would not occur after 1:30 a.m. local.
The middle-of-the-night launch will occur some time between 12 midnight and 1:30 a.m. local (3:00-4:30 a.m. EDT; 0700-0830 GMT). The actual target liftoff time has not yet been revealed.
Read our launch preview story.