Late Wednesday night, the United Launch Alliance’s large Delta IV heavy rocket landed again within seconds of taking off from its Florida launch pad. But once again, the launching scrub was done.
After the automatic ignition of the rocket in T-70 seconds, both the booster and its valuable National Reconnaissance Office fees are said to be safe. Because the abortion was started just before the rocket’s main RS-68 engine began to ignite, the delay before the next launch attempt could be less than a week.
“The terminal countdown sequencer rack engine detected an unexpected condition before the start sequence,” the company said an hour after the scrub. “The TCSR, which controlled the final 10 seconds of the countdown, was done as intended and the grip began securely in the T-7 seconds. The team is currently reviewing all the data and will determine the way forward.”
Wednesday night’s solution to the NRL-44 mission, which arrives in Florida just before midnight, is the latest setback in an attempt to remove the mission from the launch pad.
Although it is not clear if the root cause of the scrub is sitting on a rocket or with ground systems, the United Launch Alliance is having difficulties with the launch pad infrastructure in the Space Launch Complex-37, which supports the Delta IV Heavy Booster.
The launch has been scrubbed three times, leading to delays of more than a month, due to issues with different ground systems: a regulator that delivers high-pressure helium on board to the rocket; The swing arm retraction system of the launch pad, which retracts fuel lines and other attachments from the rocket before the lift lift f; And hydraulic leaks in the mobile service tower.
Ars reported Wednesday that the combination of aging infrastructure on the launch pad, which is now about 20 years old, and the relatively low flight rate of about one Delta IV mission a year could contribute to this delay.
The Colorado-based launch company has already retired the single-core Delta IV rocket and plans to fly the Delta IV heavy rocket four more times before retiring in favor of the more cost-effective Vulcan-Centurion booster after the NROL-44 mission. . Of those four flights, only two will depart from the Space Compound Complex.
In response to inquiries about these issues before Wednesday night’s scrub, Tory Bruno, head of the United Launch Alliance, told Arsen: “The reduced tempo of the Delta launch is definitely a factor. We will modify our operations readiness process for the remaining Delta IV heavy missions. To avoid the type of issues seen here. “