Boeing's Starliner set for extended stay at the ISS as engineers on Earth try to recreate thruster issues Boeing's Starliner spacecraft is set to spend a little longer attached to the International Space Station (ISS) as engineers on the ground work to recreate the oddities seen in orbit. During a briefing on July 10, mission managers admitted that engineers had not been able to recreate the conditions that caused problems for the …
The thrusters that failed are also used for the undocking and re-entry maneuvers.
As with docking, there is redundancy, but if they cannot identify why they failed they cannot rule out losing the backups too.
Fortunately undocking requires far less precision, they just need to get away. Leaving slower than intended is also ok.
Re-entry requires a precise amount of delta-v, but the capsule will passively stabilise orientation as long as it's not too far away from the right angle.
They're also aiming for the sea, which is pretty big.
In short, they've got big margins for error. Though it might be a rough ride.
"I can't find anything on any NASA publication that considers there is any risk that deorbit wouldn't be possible."
It's in LEO. It *will* deorbit, eventually. The big question is whether we are still able to control when and where?
On the first flight, the software was fucked up and fired the thrusters to the point they were going to run out of fuel - until NASA mission control noticed and stopped it.
If I remember correctly they had problems with the fuel valves on the second mission. They got damp, and corroded. Nobody expects it to be humid on the pad in Florida right? They launched anyway but I don't think the mission was without its problems.
We're told that 5 of the 8 thrusters failed at some point, but that it was a software issue. Which was rectified. However the astronauts in this article said that they had degraded performance during docking, that they could feel. Which suggests that it wasn't fully fixed. Thrusters that might stop, and require a system reboot to get started again is one thing. Bad - but relatively predictable, maybe even relatively safe. Thrusters that fail due to software and then come back with reduced performance are even less safe and predictable.
I'm a bit suspicious. They have to say it's ready for an emergency return. Because the only alternative to that would be to send a crew Dragon up to rescue them (or at least be on standby as a lifeboat). Unless there's spare seats in the one that's already up there? It's obviously safer to leave them up there and learn more about the problem than to return to Earth immediately. There's a Dragon supply capsule going up in August, so presumably they could bung in flightsuits for them - if the Boeing ones aren't compatible?
Are Boeing going to have to do another test flight repeat - at their own expense?
Surprisingly (not surpisingly?) yes they did.
For some reason they couldn't find 45 days to ground test the thrusters either time in an effort to sort that out.
For some reason they have now managed to find 45 days to ground test them looking for a solution, while two astronauts wait in space testing as well.
During the first test, the Mission Elapsed Time clock failed, causing thrusters to burn too long and fail - they had data on that.
Correct the clock failure, don't bother about the thrusters - if the clock doesn't fail again, the thrusters won't burn too long and won't fail...probably.
For the second test, a couple of the thrusters fail to fire, but there is redundancy, and the other thrusters pick up the slack - they also have data on this.
(there were also many 'stuck' valve issues prior to that test flight, but it eventually did go up and down nominally)
The unkind would say that 2+2 was not considered, or if considered discarded. Firing too much causes an issue + Individual thrusters can fail to fire = when thrusters fail to fire, even with redundancy, the remaining thrusters burn longer to compensate.
So how many thrusters can overheat and fail before the remainder also begin overburning? Well I think they just found that out, on a crewed flight.
This time it appears that it wasn't the 'clock' which caused an 'overburn', and it wasn't thrusters failing to fire, but software allowing individual thrusters and/or thrusters too close to one another, to fire too many times - many corrections = overburn.
What was different from this mission compared to nominal test flight #2 I do not know. Why were the thrusters correcting/ firing so much this time and not last time?Maybe they were correcting just as much last time, but just in a different sequence which also happened to be just enough not to cause overheating and shutdown - only NASA, Boeing, and Aerodyne know.
It's possible they could spread the corrective burns around the pods of thrusters to keep overburn/ overheating down with a software re-configuration.. or maybe they could have done that in the first place...
It should be acknowledged, this is designated as a crewed test flight - so y'know, they're testing...
Probably the on orbit ISS testing the astronauts are doing, is going through every permutation of firing sequences/ compensation depending on how many thrusters are available to them at any given point during de-orbit orientation (the problem thrusters will orientate, different thrusters will actually do the burn)
I suppose a vague analogy would be Ken Mattingly running the permutations on the Main Bus B Undervolt on Apollo 13 and having the crew run identical sequences.
Which is probably why Butch and Sunny say they are confident of returning in Starliner - they've spent over a month now running the numbers. They believe they'll have the minimum thrusters they'll need, and understand how to fire them accordingly in any given circumstance.
I'm no rocket surgeon, so that is an oversimplification as I understand it, and I'm sure I'll be corrected by someone.
*insert shrug
Boeing have an army of skilled cost plus accountants and first rate lobbyists. Just yesterday they got congress to include NASA research for SLS in the next draft SLS funding law. Congress want to know:
*) What would it take to increase SLS's launch rate to twice a year from the current half a launch per year. ($X billion per year extra funding in a cost plus contract.)
*) When would that capability be ready? (When voters start to complain it is years behind schedule.)
*) Who would buy the extra SLS launches? (Only those required to do so by law.)
*) What would be the cost and schedule savings from reduced transit times to deep space? (Swamped by at least $1B cost to stop SLS's strong torsional vibrations destroying the payload.)
*) What it would take to get commercial customers to launch with SLS? (A law mandating SLS use, $2B subsidy per launch and some actual SLS rockets not required for Artemis.)
Congress awards SLS more funding than NASA asks for. Boeing's lobbyists are that good.
I'd get SpaceX or Roscosmos to bring the crew back and send the Starliner back unmanned. If it breaks, it breaks.
Its already proven to be worthless. It doesn't offer anything novel, the only new thing that was said about it per the press release was that "it wasn't Russian". Its already cost a fortune, twice what was given to SpaceX for the same job, and Boeing hasn't really delivered. Continuing to develop it is a waste of resources, resources which would probably be better deployed in fixing the problems in their aircraft business.
As it's Boeing involved and NASA has $5.8B into it neither of them is going to present us with anything other than rose coloured assessments until they are forced to call it a failure.
It is trash, it is too expensive, too small, too far behind technologically, and completely unreliable.
Scrap it, call it a day and never let Boeing near another NASA project again. Better yet just end them as a company for their criminal behaviour.
Boeing are too big to be allowed to fail, they are too central to US space and defence activity, and in civil aircraft they are too important to the US economy.
So if they can't fail, what sanctions can be imposed upon them? Even if airlines impose their own slowdown in orders (as appears to be the case, with few or no recent orders for the 737 Max), Uncle Sam has to bail the company out if it gets too bad.
I suppose the Government could put them in "special measures" and appoint a team of their own bean counters and maybe some non-Boing engineers to oversee things and call stuff out they think is wrong, wasteful, bad practice etc. For example, no c-level bonuses, golden parachutes or other benefits for them until it's deemed safe to remove the "special measures". Any c-level choosing to not accept the new regime gets to leave with nothing, especially not any shares tied to their salary, if they so choose, but the prospect of some bonuses if they stay at least 2 years and maybe they get to keep any shares "earned" as part of their salary in previous years. Oh, and anyone leaving is banned from selling any Boeing shares for five years. They need something to encourage them to stay and/or at least wish Boeing a speedy recovery if they want those share to have any value when they are eventually allowed to sell them :-)
I suspect that the oversight arrangements you suggest aren't too different from the safety regulator's current plan. Whilst I'd agree with the limits on the execs payouts, many perhaps most of those responsible for putting Boeing in its current situation have already bailed out with fat payoffs, full vested options and paid out bonuses.
I'm surprised Mister Rescue Submarine is so silent. Are his handlers finally getting through to him or is he distracted by Shitter still being a Shitshow - and grabbing a $40+billion "salary" from Tesla before it too goes down the drain?
He has one shining star that is SpaceX And Starlink, that's two... Two shining stars, SpaceX and Starlink; enough people talk about sending a Dragon up - I'm just amazed that he hasn't spouted off on this topic, just like he did years ago with the kids in the cave.
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