KENNEDY SPACE CENTER, Fla. — The parachute failed to fully inflate on Blue Origin New Shepard’s final suborbital flight because a line controlling its expansion did not cut as planned.
One of the three parachutes on the New Shepard crew capsule did not fully inflate during the capsule’s descent on the NS-25 mission on May 19. The other two parachutes operated normally and the capsule landed without incident.
During a May 31 briefing on the upcoming manned test flight of the Boeing CST-100 Starliner, NASA officials said they were informed by Blue Origin of the parachute issue because parachutes on other vehicles, such as the Starliner, use similar components.
Steve Stich, NASA’s commercial crew program manager, said the parachutes are designed to open in stages called reefing to limit the load on the parachutes. “In this case, one of the parachutes was stuck in what I would call the first stage” of the reefing process, he said, limiting the opening of the parachute.
This is controlled by a strap or rope in the throat of the parachute. “What was seen was that the knives for some reason didn’t cut that line,” he said. The Starliner parachutes use a similar blade, but Stich said tests showed no evidence of problems with those used on the Starliner. This provided the “flight justification” for the launch of the Starliner.
He praised Blue Origin for sharing information about the parachute issue. “It’s a small group of people who work on these parachutes,” he said, including people from Blue Origin, Boeing, NASA and SpaceX. “They are great about sharing data with us. They don’t really have any root cause yet, and we’re continuing to follow them.”
However, Blue Origin has provided little information to the public about the parachute issue and the investigation, not mentioning it in its mission announcement.
“Our New Shepard system uses three parachutes and is designed to land safely with only one deployed,” a company spokesperson told SpaceNews on May 31. “We perform extensive post-flight reviews of every flight system and this analysis is ongoing. We continue to share data and analysis of our parachute deployments with our chute provider, NASA, and launch providers.”
The parachutes have caused problems for several manned vehicles that use them. Starliner’s crewed test flight has been delayed since last year in part to replace parachute components called “soft links” that do not meet adequate safety margins. SpaceX has faced its own challenges in developing parachutes for the Crew Dragon spacecraft, and recently noticed that one of the four parachutes opened more slowly than the others during deployment, but inflated fully.
The problems with the parachutes illustrate the challenges inherent in their design, despite decades of experience in their use in spaceflight. “It’s the only system you want to assemble itself in flight,” Jim McMichael, senior manager of technical integration at NASA’s Commercial Crew Program, said in an interview before an earlier Starliner launch attempt.
Parachute deployment takes place in a “chaotic environment” influenced by factors such as the wake the spacecraft creates behind it in the atmosphere as it descends. “Even today, with all the technology we have and everything else, as far as we’ve come with parachutes, we still can’t model parachute inflation,” he said. Once it starts to inflate, however, the models can accurately predict the loads on the system.
“Looks like it should be easy,” he concluded. “It’s still a bit difficult.”
