While I do these little summary stories once a week or so, it's rarely more than once a week, maybe it's time for a number in the title? I wonder.
From the "I can't say I'm surprised" file:
SpaceX matches the rest of the world in tonnage to space. In its Q4 2022 briefing, BryceTech reported that SpaceX lofted 142,330 kg into orbit during the fourth quarter of last year. China's space program was in second place, with less that half of that mass: 69,900 kg. China, in turn was followed distantly by NASA, Roscosmos, and Arianespace. SpaceX's cumulative total, mainly Starlink satellites, nearly matched the cumulative total of all other space agencies and companies in the world.
In response to news about this, SpaceX founder Elon Musk replied that SpaceX intends to nearly triple its mass to orbit this year. "This year should average around 400 tons (400,000 kg) of useful mass to orbit per quarter," he said. Presumably this means not just an increase in the cadence of Falcon 9 launches, but also some operational Starship missions toward the end of '23 that begin to carry Starlink satellites.
Virgin Orbit updated the failure analysis of their UK mission that didn't make orbit. This Tuesday, Virgin Orbit updated the status of their failure analysis on the mission they launched from the UK that didn't achieve orbit. The last time I had any information on this was January 18, so a month to the day ago.
The investigation team is utilizing a comprehensive fault tree, a very detailed timeline, and several other products to conduct the investigation in a rigorous manner. Key observations at this point in the investigation:
- The data is indicating that from the beginning of the second stage first burn, a fuel filter within the fuel feedline had been dislodged from its normal position.
- Additional data shows that the fuel pump that is downstream of the filter operated at a degraded efficiency level, resulting in the Newton 4 engine being starved for fuel. Performing in this anomalous manner resulted in the engine operating at a significantly higher than rated engine temperature.
- Components downstream and in the vicinity of the abnormally hot engine eventually malfunctioned, causing the second stage thrust to terminate prematurely.
- The early thrust termination ended the mission, and the second stage and its payloads fell back to Earth, landing in the approved safety corridor in the Atlantic Ocean.
A fuel filter. I'd say it's the kind of part that just doesn't attract
attention; ordinarily they just do what they do and nobody ever notices
them. Until they don't.
Virgin Orbit's Boeing 747 Cosmic Girl, used to carry their Launchers' upper stages beyond the densest part of the atmosphere. Virgin Orbit photo.
The first launch of Japan's H3 heavier lift rocket was aborted (video) early on February 17th (1:37 UTC or 10:37 AM local time) shortly after main engine ignition but before liftoff. The liquid-fueled main engines ignited but the strap-on solid rocket boosters did not. At just over 25 hours since the malfunction, there are no more updates.
Like its predecessor from 2001, the H2-A and the H2 before that, the H3 is built by Japan's Mitsubishi Heavy Industries, a private sector contractor. For more background on the vehicle and its long trip through development see this Ars Technica article.
Now the question is why did the designers include a fuel filter at all? I would have expected the fuel in the 2nd stage to have been processed and filtered clean before loading. If they have contamination issues AFTER loading then the tank and its lining should have been redesigned. It looks a lot like management decided to address the symptom instead of the problem.
ReplyDeleteMan, I'd like to see what a fuel filter would look like for the Starship booster!
DeleteI suspect that the reason for adding a fuel filter is out of an abundance of caution. Fuel filters don't usually cost that much, don't take up too much space or added weight, and if for some reason there is a problem with the fuel, the filter should mitigate it to allow a successful mission.
DeleteMost of us that have worked as designers are pretty familiar with Murphy's Law, and we strive to give his minions as few opportunities to wreak havoc as we can.
I have to say I was a bit surprised when I first ran into mention of a filter in a rocket fuel system, thinking basically what Rick T started the comment thread with. I eventually thought it must have been something they found they needed, and probably found the really hard and expensive way. The old, "better to have one and not need it than need it and not have it" idea.
Delete