Boeing’s space division seems to have made yet another blunder in relation to its Starliner capsule. Even though the capsule’s first mission (the Orbital Flight Test, or OFT) was already a failure due to a timer failure, another error has been found in the capsule’s software which could have destroyed the Starliner vehicle altogether. This has brought much more serious repercussions as it, if not discovered, could have resulted in the deaths of every astronaut onboard a future Starliner.
The OFT was supposed to be one of the last steps in Boeing’s development of the CST-100 ‘Starliner’, a new capsule developed under the Commercial Crew Development (otherwise known as CCDev) contract. This contract, issued by NASA, is aimed to minimize development costs through private investment and development, and actually includes two space transportation vehicles; the first is the previously mentioned Starliner, while the other is SpaceX’s Crew Dragon. By doing this, NASA hoped to provide redundancy both in regards to development and flight operations.
SpaceX has recently achieved enormous success with both a stunningly successful orbital flight test (known as Demo-1, but essentially the same as the Starliner’s OFT) and in-flight abort test, which has proved that the vehicle is safe and able to fly. However, Crew Dragon was delayed by an explosive ground test failure, which resulted in the obliteration of the capsule used for Demo-1. Thankfully, no-one was injured, but SpaceX still had to make an official investigation into the failure and fix the underlying issue (a leaky valve).
However, Starliner has run into similar issues with little success. Its abort test, while successful, still had a parachute fail on its descent. A test of the capsule’s service module resulted in a leak of the module’s toxic fuel, delaying the OFT by months. Last, a Mission Elapsed Timer failure on the OFT itself led to a planned rendezvous with the ISS becoming impossible, thereby failing the mission. But all these mistakes and accidents were without people at serious risk, or at least could have posed little risk to the lives of astronauts. (Boeing previously claimed that astronauts could have prevented the OFT’s failure, and allowed for an ISS rendezvous.)
This latest blunder is far more serious, as is displayed by NASA Administrator Jim Bridenstine’s actions, which were to hold a media teleconference detailing some of the Starliner’s issues before NASA and Boeing’s investigative review team had finished their assessment of the flight. Bridenstine explained his actions by saying that he hosted the conference in the “interest of transparency”, thanks to the OFT having “lots of anomalies”.
However, it seems that NASA is more concerned about the culture of Boeing’s software development, as Doug Loverro, the head of NASA’s human spaceflight section, stated that the software anomalies were “likely only symptoms…we had numerous process escapes in the design, development, [and] test cycle for software…We have a more fundamental problem…” This is highly worrying, especially when considering Boeing’s disastrous software failures with the Maneuvering Characteristics Augmentation System (MCAS) system on the Boeing 737, which have claimed 346 lives on two separate flights. Clearly, this is also at the top of NASA’s mind.
The anomaly in question pertains to the Starliner’s Service Module disposal sequence, which requires that it fire several thrusters to move away from the crew module just before reentry. However, during the OFT, a software check was performed following the Starliner’s malfunction during orbital insertion. This check discovered that the service module’s code was sub-par, and could have led to it colliding with the crew module. The reason as to why the code was sub-par apparently lies in the difference of whether the crew module was attached to the service module or not. The differences would require a “different valve mapping”, however, there were no differences between the scenarios. Basically, the service module’s thruster firings would have acted as if the crew module was still there.
These improper thruster firings could have been dangerous, as said by Boeing’s Senior Vice President, Jim Chilton; “It can’t be good when two spacecraft are going to contact.” In fact, in the words of NASA’s Aerospace Safety Advisory Panel member Paul Hill, the anomaly had “the potential for catastrophic spacecraft failure”. This should be taken incredibly seriously, as such an anomaly could kill every person onboard the spacecraft through either damage to the heatshield or structural damage to the capsule.
Another problem encountered was with the space-to-ground communications. During the initial stages of the flight, communications with the capsule were spotty, which had an immediate impact on the ground control team’s ability to fix Starliner’s failure during orbital insertion. This was apparently due to a “high [radio] noise floor”, which prevented the ground from contacting NASA’s Tracking Data and Relay Satellites (TDRS), which would then contact Starliner. This ‘high noise floor’ has been attributed to nearby cell phone towers.
As a result of these extensive failures, NASA has ordered an Organizational Safety Assessment of Boeing’s work on the CCDev contract, similar to that which SpaceX went under following its CEO, Elon Musk, smoking marijuana during an interview. NASA had previously ordered a more limited review of Boeing, but they are obviously determined to avoid any future issues.
This investigation is more focused on how the numerous software issues managing to slip their way through safety checks that “should or could have uncovered the defects”. However, NASA has also shouldered some of the blame, with Loverro stating that “Our NASA oversight was insufficient. That’s obvious. We recognize that. I think that’s good learning for us.”
It is encouraging to see that NASA is clearly thinking about its role in the Starliner OFT’s failure, but this comes at the tail end of a series of failures by Boeing. Its reputation in air and space, while previously unchallenged, has fallen drastically thanks to the numerous accidents or mishaps with CCDev, the 737 Max and SLS. Boeing’s actions have resulted in widespread outrage, and other companies are rapidly exploiting the lack of trust or goodwill remaining for the brand. Boeing will have to tread carefully in the following weeks, as both they and NASA decide what to do following this latest failure.
It remains to be seen whether the next test will be crewed, or if it will just be a repeat of the failed OFT. However, SpaceX has almost certainly won the race to develop NASA’s next spaceflight system.
Featured image from Boeing
https://news.google.com/__i/rss/rd/articles/CBMiV2h0dHBzOi8vYWVyb25hdXRpY3NvbmxpbmUuY29tL2Z1cnRoZXItcHJvYmxlbXMtd2l0aC1ib2VpbmdzLXN0YXJsaW5lci1jYXBzdWxlLXJldmVhbGVkL9IBAA?oc=5
2020-02-09 17:35:30Z
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