ULA successfully launched and deployed the OA-6 Cygnus spacecraft to its desired orbit on Tuesday, March 22. During the launch, the system experienced a premature first stage shutdown. The first stage cut-off occurred approximately 6 seconds early; however the Centaur automatically compensated by burning longer.

The robustness of the system achieved mission success, delivering Cygnus to a precise orbit as planned. The ULA engineering team is continuing to review the data and has developed initial fault trees with our industry partners.

The team has been successful in isolating the anomaly to the first stage fuel system and its associated components. Per standard processes when a flight anomaly such as this has been identified, ULA and our partners have formed a robust review team with full collaboration with major customers.

The review will thoroughly assess all flight and operational data to determine root cause and identify appropriate corrective actions prior to future flights.

earlier report
United Launch Alliance Successfully Launches 7,745 Pounds of Cargo to International Space Station
Cape Canaveral Air Force Station FL (SPX) Apr 05, 2016 A United Launch Alliance (ULA) Atlas V rocket carrying the OA-6 Cygnus resupply craft to the International Space Station (ISS) lifted off from Space Launch Complex-41 on March 22 at 11:05 p.m. EDT.

Approximately 21 minutes later, the spacecraft successfully separated from the Centaur upper stage at its initial orbit, where it will rendezvous with the ISS. The mission was flown for Orbital ATK under NASA's Commercial Resupply Services contract, and, with a payload of more than 16,000 pounds, was the heaviest payload to launch on an Atlas V to date.

"ULA is honored to be a part of the team that delivered more than 7,700 pounds of cargo to the astronauts aboard the ISS and CubeSats to be deployed after Cygnus separates from the ISS," said Gary Wentz, ULA vice president, Human Launch Services. "Congratulations to our mission partners at Orbital ATK and NASA on another successful launch that will help advance our scientific knowledge on Earth and in space, and inspire the next generation of space explorers."

This mission was launched aboard an Atlas V Evolved Expendable Launch Vehicle (EELV) 401 configuration vehicle, which includes a 4-meter-diameter extra extended payload fairing. The Atlas booster for this mission was powered by the RD AMROSS RD-180 engine and the Centaur upper stage was powered by the Aerojet Rocketdyne RL10C-1 engine. It was the ULA's third launch in 2016 and the 106th launch since the company formed in 2006.

"I am also extremely proud of our engineering and mission integration teams as this vehicle flew the first flight of the upgraded boattail," Wentz said. "With every launch, we build upon our years of experience and continue to find new and better ways to launch our customers' payloads to orbit in an efficient and cost-effective manner."

Cygnus is a low-risk design incorporating elements drawn from Orbital ATK and its partners' existing, flight-proven spacecraft technologies. Cygnus consists of a common Service Module (SM) and a Pressurized Cargo Module (PCM). The SM is assembled and tested at Orbital ATK's Dulles, Virginia, satellite manufacturing facility and incorporates systems from Orbital ATK's flight-proven LEOStar and GEOStar satellite product lines. The PCM is based on the Multi-Purpose Logistics Module (MPLM), developed and built by Thales Alenia Space of Italy.

ULA's next launch is the MUOS-5 satellite for the U.S. Navy, scheduled for May 5 from Space Launch Complex-41 from Cape Canaveral Air Force Station, Florida.