Redesigning and testing part of the parachute system on the Boeing CST-100 Starliner spacecraft will delay a long-awaited crew flight test (CFT) until March 2024 at the earliest.
The problem with the parachute system was one of two issues that came to light as Boeing and NASA conducted a checkpoint review in May ahead of a planned CFT launch on July 21. The second issue is a potential flammability concern with a glass cloth tape used to protect wire harnesses throughout the capsule.
“The work that we have in front of us is relatively straightforward,” Mark Nappi, Boeing’s vice president and program manager for the Starliner program, told reporters on a conference call on Aug. 7.
The pacing item is the delivery of three modified parachutes from Boeing supplier Airborne Systems, with the last chute expected at the beginning of December, Nappi said. NASA and Boeing plan one drop test, slated for mid- to late-November, to ensure the new design meets safety requirements.
Due to a test error made early in the program, joints in the parachute system that connect the main parachute lines on the capsule to risers do not have the required 2.0 safety factor required for critical systems. The joint, known as a soft link, has been redesigned and is currently undergoing testing, Nappi said.
The company is also making progress removing, replacing and mitigating potential flammability issues stemming from widespread use of P-213 tape that covers wire harnesses throughout the Starliner capsule.
“This tape is widely used across the aerospace industry for many applications for protecting wires from abrasion,” NASA’s Commercial Crew Program Manager Steve Stich said. “The entries in the NASA database were a bit inconsistent relative to the flammability of that tape at various levels of oxygen concentration. And so it was a bit confusing as to when it could be used and when it couldn’t.”
Boeing’s remediation plan is to divide the spacecraft into 12 zones and tailor solutions for each area. “We expect to have all those zones addressed and the vehicle into some level of regression testing by the end of September,” Nappi said.
“The chutes will drive the readiness for potential launch dates,” he added. “Based on the current plans, we’re anticipating that we’re going to be ready with the spacecraft in early March.”
NASA awarded contracts to Boeing and SpaceX in 2014 to develop space transportation systems to fly crews to the International Space Station (ISS). SpaceX is preparing to launch its seventh crew-rotation mission for NASA on Aug. 25. The company has also flown three private Crew Dragon charters, with a fourth targeted to launch in late 2023.
Boeing’s Commercial Crew Transportation Capabilities contract with NASA, which covers an uncrewed and crewed flight test and six ISS crew-rotation missions, is valued at $4.4 billion as of April 30. Boeing conducted a successful uncrewed Starliner flight test to the ISS in May 2022. Its first attempt to reach the station in December 2019 failed due to software and communications problems.
Under terms of the firm, fixed-priced contract with NASA, Boeing bears the costs for Starliner repairs and modifications, which so far total more than $1.1 billion. “We are still committed, like we have been in the past,” Nappi said. “We will continue on.”
