The planned launch of a 233-foot-tall, 1.6-million-pound United Launch Alliance Delta IV rocket on Friday was delayed about three hours before it was set to blast off from Vandenberg Air Force Base with a top secret satellite, authorities said.

National Reconnaissance Office Launch 71, or NROL 71, was scheduled to lift off at 8:19 p.m., ULA said in a written statement.

But the company “scrubbed” the launch in favor of trying again 24 hours later, ULA said via Twitter.

The launch will be the private space launch company’s 132nd mission, and its second Delta IV Heavy launch in under four months. The mission is being flown in conjunction with the Air Force’s 30th Space Wing.

ULA plans to live stream the launch beginning 20 minutes before liftoff. </s> The countdown stopped 7 seconds before liftoff Saturday as a Delta IV Heavy rocket sat poised on its launch pad at Vandenberg Air Force Base for a second attempt to launch a spy satellite into orbit on behalf of the National Reconnaissance Office.

United Launch Alliance scrubbed a planned launch in the final seconds after detecting a problem, ULA said via Twitter. A previous attempt to launch the 233-foot-tall rocket on Friday was scrubbed about three hours before launch.

Small flames could be seen igniting at the base of the engines before they quickly disappeared The rocket remained still.

With favorable weather conditions, Saturday’s launch was originally slated for 8:06 p.m., but a brief stop in the countdown to troubleshoot a problem pushed the liftoff back to 8:15 p.m., the company said.

All systems were “go” until the countdown was halted just seven seconds before liftoff after a problem was detected, ULA said. The attempt was cancelled for the night, but it was not clear when ULA will try again.

The rocket carries a secret payload. It is set to deploy a classified satellite for the National Reconnaissance Office.

ULA is working in conjunction with the Air Force’s 30th Space Wing on the launch, dubbed NROL-71. </s> The launch of the Delta IV Heavy rocket, carrying a reconnaissance satellite, was called off on Saturday evening seven seconds before liftoff, United Launch Alliance (ULA) said. According to the company, the mission was put on hold due to “an unexpected condition” in one of the computing systems. The launch was supposed to take place at Vandenberg Air Force Base in California. The satellite was originally to be launched into space on Friday but that attempt was also abruptly called off due to a technical malfunction. </s> LOMPOC, Calif. — Just seconds before the planned liftoff of a Delta IV Heavy rocket with the NROL-71 payload for the National Reconnaissance Office, an automatic abort of the launch sequence was triggered.

With only a minor issue earlier in the countdown, the Dec. 8, 2018, launch attempt of United Launch Alliance’s Delta IV Heavy rocket seemed ready to fly with the classified NROL-71 payload at 8:15 p.m. PST (11:15 p.m. EST / 04:15 GMT Dec. 9) from Space Launch Complex 6 at Vandenberg Air Force Base.

However, just as the engines were about to start and excess hydrogen gas burn off began—a hold was called, which would ultimately scrub the launch.

“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,” a ULA statement reads. “The team is currently reviewing all data and will determine the path forward.”

Within minutes, the launch team verified the rocket, launch pad and payload were in a safe configuration. Shortly thereafter, it was recommended that the 233-foot (71-meter) tall, triple-core rocket be emptied of its liquid oxygen and liquid hydrogen propellant.

This was the second attempt to get the NROL-71 mission off the ground (the first was on Dec. 7). ULA has not announced when its next launch attempt will occur. This was slated to be the company’s 38th Delta IV rocket (the 11th “Heavy” variant) since the vehicle’s debut in 2002.

Should the rocket launch before the end of the year, it will be the final flight for ULA in 2018, capping off with nine missions—five Atlas V’s, three Delta IV’s (two if NROL-71 is delayed to 2019) and the final flight of the venerable Delta II rocket.

Derek Richardson has a degree in mass media, with an emphasis in contemporary journalism, from Washburn University in Topeka, Kansas. While at Washburn, he was the managing editor of the student run newspaper, the Washburn Review. He also has a blog about the International Space Station, called Orbital Velocity. He met with members of the SpaceFlight Insider team during the flight of a United Launch Alliance Atlas V 551 rocket with the MUOS-4 satellite. Richardson joined our team shortly thereafter. His passion for space ignited when he watched Space Shuttle Discovery launch into space Oct. 29, 1998. Today, this fervor has accelerated toward orbit and shows no signs of slowing down. After dabbling in math and engineering courses in college, he soon realized his true calling was communicating to others about space. Since joining SpaceFlight Insider in 2015, Richardson has worked to increase the quality of our content, eventually becoming our managing editor. @TheSpaceWriter </s> The launch of a massive rocket carrying out a mission for the U.S. agency responsible for spy satellites was called off just seconds ahead of liftoff on Saturday.

United Launch Alliance, a contractor for the U.S. National Reconnaissance Office (NRO), was expected to launch a Delta IV Heavy rocket carrying the NROL-71 mission from Vandenberg Air Force Base in California on Saturday evening.

The launch was initially delayed, then called off about 7.5 seconds before liftoff. The company said there was “an unexpected condition during terminal count.”

READ MORE: SpaceX says top secret spy satellite disappearing not its fault

“The team is currently reviewing all data and will determine the path forward. A new launch date will be provided when available,” ULA said.

A previous launch attempt was aborted on Friday due to an issue with a communication link between the control centre and launch site.

The NRO is responsible for developing, launching and operating U.S. intelligence satellites. It described the NROL-71 as a “national security payload designed, built and operated by the NRO.” </s> If you would like to see more articles like this please support our coverage of the space program by becoming a Spaceflight Now Member . If everyone who enjoys our website helps fund it, we can expand and improve our coverage further.

A dramatic automatic abort 7.5 seconds before the planned liftoff of a United Launch Alliance Delta 4-Heavy rocket Saturday night kept the towering launcher on the pad at Vandenberg Air Force Base, California, with a top secret spy payload for the National Reconnaissance Office.

The 233-foot-tall (71-meter) rocket was counting down to launch at 8:15 p.m. PST Saturday (11:15 p.m. PST; 0415 GMT Sunday), but an automated sequencer detected a technical issue and triggered an abort.

“Hold hold hold,” a member of the ULA launch team declared on the countdown net.

A burst of flame appeared at the base of the rocket, a normal occurrence in the final seconds of a Delta 4 countdown as sparklers activate near the engines to burn off excess hydrogen gas before ignition, a measure aimed at eliminating the risk of a fireball or explosion.

It was not immediately clear whether any of the rocket’s three Aerojet Rocketdyne RS-68A main engines started their ignition sequences, but a statement later released by ULA said the computer-controlled countdown sequencer ordered an abort at T-minus 7.5 seconds.

In the statement, ULA said the abort was “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,” ULA said.

The Delta 4-Heavy is made up of three Delta 4 first stage boosters bolted together, each with an RS-68A engine burning liquid hydrogen and liquid oxygen propellants. ULA commands the three RS-68A engines to start in a staggered sequence, beginning with the starboard engine at T-minus 7 seconds, followed two seconds later by ignition of the center and port engines.

The timing of the abort at T-minus 7.5 seconds suggests the countdown stopped around a half-second before the first of the Delta 4-Heavy’s three main engines was supposed to ignite.

ULA’s launch team quickly “safed” the rocket, disarmed ordnance, and drained the Delta 4-Heavy of its supply of cryogenic propellants. The launch team did not set a new target launch date, but officials were instructed to plan for an extended turnaround after Saturday night’s scrub, and the Delta 4-Heavy flight was expected to be delayed at least a few days.

A similar cutoff in the final seconds of a Delta 4 countdown in 2010 resulted in a three-day slip to resolve the problem responsible for the abort — and replace the hydrogen burn-off sparklers on the pad — before the rocket successfully launched from Cape Canaveral with a GPS navigation satellite.

The upcoming mission from Vandenberg, located around 140 miles (225 kilometers) northwest of Los Angeles, is codenamed NROL-71 by the National Reconnaissance Office, which owns the U.S. government’s classified intelligence-gathering satellites. The NRO has not released any information about the spacecraft aboard the Delta 4-Heavy, but independent observers of NRO space launches believe the payload is heading for an unusual, high-inclination orbit, and is likely a new Keyhole-type high-resolution optical imaging satellite, with an Earth-pointing telescope capable of capturing extremely detailed imagery of sites around the world for review by government intelligence analysts.

The Delta 4-Heavy is ULA’s biggest rocket, and can loft up to 51,950 pounds (23,560 kilograms) of payload mass to a 120-mile-high (200-kilometer) low Earth orbit inclined 90 degrees to the equator.

The heavy-lift variant of the Delta 4 rocket has launched 10 times to date. The NROL-71 mission will be the 11th flight of a Delta 4-Heavy, and the 38th mission overall for the Delta 4 family since November 2002. It will also be ULA’s ninth and final launch of the year, following five Atlas 5 launches, a pair of Delta 4s, and the final liftoff of the company’s now-retired Delta 2 rocket.

A launch attempt for the NROL-71 mission Friday night was scrubbed after the Delta 4 team encountered a problem with a communications link between the control center and the rocket associated with the holdfire system. </s> United Launch Alliance will use a Delta IV Heavy rocket to launch the NROL-71 mission for the National Reconnaissance Office.

This will be 132nd mission for United Launch Alliance and ULA's second Delta IV Heavy launch in less than four months. It is the 382nd Delta launch since 1960, the 38th for a Delta IV rocket since 2002 and the 11th Delta IV Heavy.

This comes a day after SpaceX's successful launch on a mission to resupply the International Space Station.

Though the cargo-packed Dragon spacecraft made it safely to orbit and is scheduled to arrive at the ISS around 6 a.m. Saturday, the 156-foot-tall rocket stage did not share the same fate – instead of Landing Zone 1, it automatically targeted a wet landing in the Atlantic Ocean about two miles offshore.

USA TODAY will stream the Delta IV Heavy rocket launch live in the player above. </s> United Launch Alliance (ULA) successfully completed its first flight of 2018 on Friday, January 12, two days after high ground winds forced the scrubbing of the initial launch attempt and one day after a ground system valve forced a second scrub.

A ULA Delta IV Medium+(5,2) carrying the classified NROL-47 payload lifted off from Vandenberg Air Force Base’s Space Launch Complex 6 at 2:11 p.m. PST (5:11 p.m. EST). The mission was ULA’s 27th flight for the National Reconnaissance Office (NRO) and the 36th flight of the Delta IV rocket, which first flew in 2002. This flight marked the first of 2018 for ULA.

“As the nation’s most trustworthy launch provider, today’s launch exemplifies ULA’s ongoing commitment to 100 percent mission success,” said Will Crawford, ULA’s NRO program manager via a release. “My sincere thanks to the entire ULA team and our mission partners at the NRO and U.S. Air Force who made this, our 27th NRO launch, possible.”

The NRO is the U.S, Government agency in charge of designing, building, launching and maintaining America’s fleet of intelligence satellites. The agency was formed in 1961 and was declassified to the public in 1992. NROL-47 is NRO’s 50th launch since 1996.

Due to the mission’s classified nature, little is known about the NROL-47 payload, but it is believed to be radar reconnaissance satellite, operating from a retrograde orbit inclined 123 degrees. NROL-47 will join the Future Imagery Architecture (FIA) satellite constellation, which flies under the code name Topaz.

The NROL-47 mission marked the final flight of the Medium+ (5,2) variant of the Delta IV rocket, which has two Orbital ATK GEM-60 solid rocket motors attached the the exterior of the rocket’s Common Booster Core (CBC) and a 5-meter diameter payload fairing. The main engine of the Delta IV is the RS-68A, manufactured by Aerojet Rocketdyne. The rocket’s second stage is propelled by an RL-10 engine.

Thursday morning’s weather report from the 30th Space Wing showed an 80 percent chance of favorable conditions, a considerable improvement over the previous day’s 40 percent. However, this was not the only variable thrown at the launch team with an issue with a ground system valve forcing mission managers to call a scrub for the Thursday, Jan. 11 launch attempt(s) as well.

United Launch Alliance’s CEO and President, Tory Bruno expressed the excitement of seeing the final planned launch of a Delta IV Medium+ (5,2) soar through California’s skies when he tweeted: “Delta is ripping the sky at incredible speed.”

The Delta IV Medium+ (5,2) rocket is part of a family of launch vehicles that are described as follows by the Colorado-based launch service provider:

The Delta IV family of launch vehicles combines design simplicity, manufacturing efficiency, and streamlined mission and vehicle integration to meet customer requirements to launch high-priority U.S. Air Force (USAF), National Reconnaissance Office (NRO), NASA, and commercial payloads to orbit.

With operational launch pads on both coasts—Space Launch Complex-37 at Cape Canaveral Air Force Station, Fla., and Space Launch Complex-6 at Vandenberg Air Force Base, Calif.—every Delta IV configuration is available to service the requirements of current and future satellite programs.

The Delta IV launch system is available in five configurations: the Delta IV Medium (Delta IV M), three variants of the Delta IV Medium-Plus (Delta IV M+), and the Delta IV Heavy (Delta IV H). Each configuration is comprised of a common booster core (CBC), a cryogenic upper stage and either a 4-m-diameter or 5-m-diameter payload fairing (PLF).

There are three variants of Delta IV M+ configuration. The Delta IV M+(4,2) uses two strap-on solid rocket motors (SRMs – GEM-60 boosters provided by Orbital ATK) to augment the first-stage CBC and a 4-m diameter PLF. The Delta IV M+(5,2) and Delta IV M+(5,4) have two and four SRMs, respectively, and 5-m-diameter PLF.

“Another successful Delta IV launch is testament to our highly engineered composite structures, unwavering commitment and exceptional teamwork to ensure dependable access to space and affordable innovation in delivering this critical asset for our nation’s security,” said Steve Earl, Vice President and General Manager of Orbital ATK’s Aerospace Structures Division via a release.

The Graphite Epoxy Motors (GEM 60) used on the Delta IV family of rockets measure some 53-feet (16 meters) in length. They burned for about 90 seconds and provided more than 560,000 pounds of thrust. These have been used on the Delta IV since its initial flight in 2002.

The GEM 60s provided additional thrust to the lone Aerojet Rocketdyne RS-68A engine located in the Delta IV’s first stage. The RS-68A engine provided an estimated 702,000 pounds of thrust during the initial phase of the flight. After staging, an Aerojet Rocketdyne RL10B-2 granted some 24,750 pounds of thrust, sending the Delta IV’s upper stage to orbit.

“The successful launch of a payload in support of our national security and that of allied forces demands the best propulsion systems available,” said Aerojet Rocketdyne CEO and President Eileen Drake in a statement issued by the company. “Aerojet Rocketdyne employees across the country work hard to ensure 100 percent mission success, and our role in yet another launch for the National Reconnaissance Office demonstrates the trust and confidence in our propulsion.”

ULA’s next planned flight is the launch of an Atlas V 411 rocket with the Space Based Infrared System (SBIRS) GEO Flight 4 spacecraft for the U.S. Air Force. At present, that mission is scheduled to get underway on Thursday, Jan. 18 from Cape Canaveral Air Force Station’s Space Launch Complex 41 located in Floridae launch is scheduled for Jan. 18 from Space Launch Complex-41 at Cape Canaveral Air Force Station, Fla. </s> A Delta IV rocket, carrying the Parker Solar Probe, lifts off from launch complex 37 at the Kennedy Space Center, Sunday, Aug. 12, 2018, in Cape Canaveral, Florida. The Parker Solar Probe will venture closer to the Sun than any other spacecraft and is protected by a first-of-its-kind heat shield and other innovative technologies that will provide unprecedented information about the Sun.

The scheduled launch of a rocket carrying a reconnaissance satellite into orbit from Vandenberg Air Force Base in Santa Barbara County that was originally scheduled for Friday and reset for Saturday was called off at T-minus 7 seconds due to a problem detected by the Terminal Countdown Sequencer Rack, according to United Launch Alliance.

The launch was not immediately rescheduled.

Prior launches from Vandenberg have created spectacular light displays over the Southern California and the southwestern United States.

The United Launch Alliance rocket was initially set to take off at 8:19 p.m. Friday, but roughly three hours before launch time, it was scrubbed due to "an issue with a redundant communication link between the control center and launch site.''

If liftoff had been successful Saturday, the launch would have been the second rocket to take off this week from Vandenberg AFB. Hawthorne-based SpaceX launched a Falcon 9 rocket from the base Monday, carrying 64 satellites into orbit.

The latest launch is being carried out by United Launch Alliance, a joint venture of Lockheed Martin and Boeing. ULA's Delta IV Heavy rocket will carry a secretive satellite for the U.S. National Reconnaissance Office.

"We are proud to launch this critical payload in support of our nation's national security mission,'' Gary Wentz, ULA vice president of government and commercial programs, said in a statement. "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.''

According to the company, the Delta IV Heavy rocket includes three Rocketdyne liquid hydrogen/liquid oxygen engines that can produce a combined 2.1 million pounds of thrust.

ULA has carried out 27 launches for the National Reconnaissance Office over the past 12 years.

Copyright City News Service
The ULA launch of a Delta IV Heavy rocket carrying the NROL-71 mission is called off 7 seconds before liftoff time.