More problems uncovered during testing of the James Webb Space Telescope
During ground tests of the James Webb Space Telescope engineers have discovered an additional quite astonishing problem that will certainly delay the project again.
In a presentation at a meeting of the National Academies’ Space Studies Board here May 3, Greg Robinson, the JWST program director at NASA Headquarters, said some “screws and washers” appear to have come off the spacecraft during recent environmental testing at a Northrop Grumman facility in Southern California.
Technicians found the items after the spacecraft element of JWST, which includes the bus and sunshield but not its optics and instruments, was moved last weekend from one chamber for acoustics tests to another to prepare for vibration testing.
“Right now we believe that all of this hardware — we’re talking screws and washers here — come from the sunshield cover,” he said. “We’re looking at what this really means and what is the recovery plan.” The problem, he said, was only a couple of days old, and he had few additional details about the problem. “It’s not terrible news, but it’s not good news, either,” he said. [emphasis mine]
The absurd spin expressed by the program director above is garbage. This is unbelievable and entirely unacceptable. On spacecraft, especially those that are not planned for in-space maintenance like Webb, screws are routinely sealed with some form of glue so that they will not unscrew themselves during the vibrations of launch. This is standard space engineering and has been for more than a half century.
That some screws came off Webb during testing suggests a quality control problem at Northrop Grumman that is beyond comprehension.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
During ground tests of the James Webb Space Telescope engineers have discovered an additional quite astonishing problem that will certainly delay the project again.
In a presentation at a meeting of the National Academies’ Space Studies Board here May 3, Greg Robinson, the JWST program director at NASA Headquarters, said some “screws and washers” appear to have come off the spacecraft during recent environmental testing at a Northrop Grumman facility in Southern California.
Technicians found the items after the spacecraft element of JWST, which includes the bus and sunshield but not its optics and instruments, was moved last weekend from one chamber for acoustics tests to another to prepare for vibration testing.
“Right now we believe that all of this hardware — we’re talking screws and washers here — come from the sunshield cover,” he said. “We’re looking at what this really means and what is the recovery plan.” The problem, he said, was only a couple of days old, and he had few additional details about the problem. “It’s not terrible news, but it’s not good news, either,” he said. [emphasis mine]
The absurd spin expressed by the program director above is garbage. This is unbelievable and entirely unacceptable. On spacecraft, especially those that are not planned for in-space maintenance like Webb, screws are routinely sealed with some form of glue so that they will not unscrew themselves during the vibrations of launch. This is standard space engineering and has been for more than a half century.
That some screws came off Webb during testing suggests a quality control problem at Northrop Grumman that is beyond comprehension.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
A Northrop Grumman rocket scientist as the JWST spacecraft is being removed from the acoustic chamber:
“- Ehum, do those screws and washers on the floor come from the scope thing?”
https://www.youtube.com/watch?v=NeOnLwi9CtQ
Well the crew at NG have not reached the level of the NOAA-19 debacle where the guys at LockMart forgot to tell everyone that they pulled the bolts holding the satellite to the transport cart.
https://en.wikipedia.org/wiki/NOAA-19#/media/File:NOAA-N%27_accident.jpg
I have anyways wanted to a video of they’re reaction when it fell over. That and the reactions on phone to the bosses. “You did WHAT to it?!?”
Aren’t there always a few screws left over when you put something together?
NOAA-19 barely missed the guy sitting on the blue chair at the table to the right. It came crashing down before even reaching the launch pad. Did not enter orbit, the self-gravity drive generated a too short ballistic trajectory. Lockheed Martin.
If the screws and washer really did come off the spacecraft, then this is a quality control matter. It means that they were not properly torqued, so the staking of the screws would (or should) not have been performed, nor would anyone have put on torque striping. (Robert described staking with his comment about sealing the screws. Torque stripe does not seal the screw but is a little paint, or whatever, that indicates that the screw has been torqued.)
Missing poor workmanship is poor quality control. You really, really don’t want to be finding loose screws during test. It makes everyone wonder how much more poor workmanship that there is.
I worked at a place that had screws come out during an acoustic test (vibration from sound, not shake-table vibration — it gets loud inside a fairing). It was due to the screws having been installed but not torqued. A miscommunication left the screws untorqued. After the investigation and corrective actions were over, I wound up being the engineer in charge when new screws were reinstalled, and the technician missed one screw when he was torquing. I pointed it out to him, but how bad would it be for the same error to show up twice in a row? That company now requires a quality assurance person, in addition to the engineer, to witness all torque operations on flight and ground support hardware.
As for NOAA-19, I went to work for Lockheed Martin a few years after the incident, after having worked for them shortly before the incident. They had a complete change in attitude. “Zero Defects” went from being an old slogan to a continual training program. I worked for the manager who had had to explain to the government customer how their satellite got dropped (he had not been there when it fell). It was quite a story of miscommunication (root cause). I believe that corporate culture also was a factor.
Before NOAA-19 fell, I went to work for another company that had just dropped a satellite in a surprisingly similar manner. They asked me, as fresh eyes, whether I thought it could happen again, and I said yes for four reasons. The top of the list was the attitude that everyone had, thinking that it could not happen again, because people would protect against making such an error. Such an attitude reduces, not increases, vigilance against such an occurrence, and it did not teach anyone how to prevent such errors from happening again.