ULA statement: “Initial indications were with a ground system and we are working to confirm the exact cause.”
WASHINGTON – The United Launch Alliance has not yet confirmed what exactly caused the dramatic interruption in the launch of the Delta 4 Heavy just three seconds before takeoff on August 29.
“We are in the middle of an in-depth investigation to determine the root cause of the NROL-44 disruption,” ULA spokeswoman Julie Arnold told SpaceNews.
The missile, carrying a classified spy satellite from the National Intelligence Service, remains on the ground in the space launch complex-37 in the Air Force on Cape Canaveral in Florida.
During the ignition sequence before the scheduled takeoff at 3:28 a.m., fire was seen at the bottom of the rocket̵
“The initial indications were with a ground system, and we are working to confirm the exact cause,” Arnold said. “The system stopped at T-minus 3 seconds because the starting conditions were not met in order to continue starting the main engine.”
After the pad breaks, which occurs less than five seconds after takeoff, the ULA needs at least seven days to replace the ground system’s spent hardware and validate the flight systems, Arnold said.
The company will need more time to complete the investigation, Arnold said before setting a new target date for the launch of the NROL-44.
“We will take the time to thoroughly review the Delta 4 Heavy to identify, repair and re-test the system. “Once that’s over, we’ll set a new launch date,” Arnold said.