Posted on 09/24/2021 4:47:02 AM PDT by BenLurkin
...two months after it first discovered an issue with some of the valves in the spacecraft’s service module, the company still doesn’t know with 100 percent certainty what caused 13 of those valves to remain shut when they should have been open...
...the company might even have to swap out the spacecraft’s service module for a new one...
“We got very close to launch without having identified the valve problem,” said George Nield, a panel member who previously oversaw the Federal Aviation Administration’s office of commercial space transportation. “Are there any changes to hardware inspection, testing, vehicle processing or checkout that would minimize the chances of that happening in the future?”
He also said there “were some rather significant differences in how several safety issues were assessed between NASA and Boeing” during the flight readiness reviews.
Boeing’s first flight attempt, in December 2019, suffered a series of problems due to software and communications issues that prevented the spacecraft from docking with the station and forcing controllers to shoot software fixes to the capsule in midflight
(Excerpt) Read more at washingtonpost.com ...
Meanwhile, SpaceX and Blue Origin are launching tourists in their capsules.
doesn’t know with 100 percent certainty what caused 13 of those valves to remain shut when they should have been open...
Software. Even in autos it’s getting too complex to predict.
Time to just cancel their contract. And while they’re at it they could cancel SLS, Artemis, and Orion.
Blue origin launches. Wow. Straight up then Down. Impressive. Not.
Soon as Starship orbits the earth with reusable rockets the entire situation in space is changed forever.
Problem Identified
MADE IN CHINA
I admit, Blue Origin is an also-ran compared to SpaceX, but at least their capsule got off the ground, unlike Boeing’s.
Blue origin dipped their toe at the edge of space and came down.
SpaceX went up past Hubble and stayed for three days.
Boeing ain’t going.
It's better to have Soviet-style fake competition than to spend less money getting the work done by people who have demonstrated that they know what they're doing. /s
Boeing has been tethered to fedgov for so long it’s become as efficient as fedgov. Overweight sloth.
Yes, SpaceX has been much more impressive than Blue Origin. But at least Blue Origin’s capsule has gone further than Boeing’s.
Boeing started to go downhill once they moved the HQ from Seattle to Chicago.
In the mean time all the true private spacecraft manufacturers are moving ahead with success after success. Maybe there’s a lesson in this for NASA?
Software. Even in autos it’s getting too complex to predict.
Should be fairly easy to diagnose. If they can pull the valves, or even most of them, and cycle them - do they open/close when signaled to open close? You can find design/manufacturing problems that way, or rule out a hardware failure.
If the valves work, check the drive circuitry and wiring. When commanded, does the signal get there at the proper voltage and with enough current to actuate the valve?
If all that is working then it is a software problem - for some reason the system did not command the right state.
If it were me, (and yes I've designed/coded software for embedded systems) for every bit of external hardware outside the control system - both sensors and actuators - I'd have a very, very simple module that interfaced to them. As in dirt simple, too simple to screw up. Said module would always log any change of state.
That way you'd always be able to go back and figure out if a command was given to the hardware (or not), when, etc. Even though this is rocket science, this isn't "rocket science" - this is computers/software dealing with the outside world 101. The outside world is messy, you have to defend yourself against it at every touchpoint.
If you're not getting the commanded state when you expect, it is your control system. This should be fairly well partitioned into higher level functions and low level functions. "Hey, we're ready for engine startup sequence." - high level. "Engine startup? That means open valves x, y, z, shut vents p, d, q..." - low level response to change of state. In general this logic should be expressed simply and clearly.
If they haven't traced through these kinds of things by now, and don't have a "smoking gun" culprit for the failure, then they have serious problems. It says their software architecture and development standards/practices don't support this kind of analysis. They're probably dealing with a mess of their own making.
13? Lucky number.
Maybe now they’ll try doing an integrated test, rather than looking at a bunch of specifications and figuring that it ‘should’ all work together.
There are today Chinese made parts in Boeing’s most recent aircraft models. Sabotage, via malware in some Chinese-made circuit board???
Well, there’s that.
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