Bahnhof Strasse
Met up with Hannah Courtoy a week next Tuesday
Probably, there's a company there that makes satellites called Surrey Satellite Technology and SpaceX is a significant shareholder.
SpaceX rockets and launches
- Thread starter rover07
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Probably, there's a company there that makes satellites called Surrey Satellite Technology and SpaceX is a significant shareholder.
editor
hiraethified
Live stream at 7.30pm tonight.
Elon Musk’s Mars colonization announcement: start time, live blog, and streaming
ferrelhadley
There is no love between us anymore.
2hats
Dust.
2hats
Dust.
SpaceX have issued a statement reporting that their investigation (note conclusion not yet approved by the FAA) has traced the cause of the accident to the failure of a composite overwrapped pressure vessel (COPV) in the second-stage liquid oxygen tank. The tank buckled, LOX pooled between the COPV liner and overwrap in a void or a buckle in the liner, and then was ignited by either breaking fibres or friction. Additionally helium loading temperatures were sufficiently low that solid oxygen may have formed in places which greatly increases the likelihood of LOX pooling and friction ignition.
They plan to address this in the short term by changing the way they load fuel, and in the long term to change the design of the pressure vessel to prevent a repeat of this event.
SpaceX due to return to launch this Sunday (8th Jan) with a Falcon 9 carrying Iridium NEXT 1-10 from Vandenberg.
(Above: the 10 Iridium NEXT satellites mounted on their dispenser and being placed inside the fairing.)
They plan to address this in the short term by changing the way they load fuel, and in the long term to change the design of the pressure vessel to prevent a repeat of this event.
SpaceX due to return to launch this Sunday (8th Jan) with a Falcon 9 carrying Iridium NEXT 1-10 from Vandenberg.
(Above: the 10 Iridium NEXT satellites mounted on their dispenser and being placed inside the fairing.)
Crispy
The following psytrance is baṉned: All
More accurately, the carbon-fiber overwrapping had a buckle in it, as is inevitable when you try and fold a flat sheet around a doubly curved surface. Such voids are usually filled by the epoxy, but this one must have persisted.
pocketscience
Well-Known Member
It's hard to imagine that the engineers at space-x are using 'flat' sheets on such applications (unless of course their budgets are so tight they've taken the risk of doing it themselves to save the costs of having the components designed and built by a company with the right knowledge & hardware).
Automated Fibre Placement (AFP) and Tape Layering (ATL) for spherical surfaces have been the (aerospace) industry standard for well over a decade now. Both methods avoid having to 'fold' the material.
Her'se an ATL example;
Here's ATL;
Obvioulsly a costly solution for short production runs so they may have compromised by trying to do it themselves (unlikely) but my guess is a one off material or manufacturing issue.
Such a part would normally go through extensive destructive testing before approval.
Be interesting what the faa has to say.
Crispy
The following psytrance is baṉned: All
pocketscience
Well-Known Member
Yep,, the robot arm/ prepreg fibre or tape variant is normally used for compex surfaces with awkward ply layups.
For cylindrical parts (such as the pressure cylinders or even aircraft fuselage sections) some companies use a revolving mandrel as a jig and apply the prepreg fibres through a kind of weavers loom.
For cylindrical parts (such as the pressure cylinders or even aircraft fuselage sections) some companies use a revolving mandrel as a jig and apply the prepreg fibres through a kind of weavers loom.
pocketscience
Well-Known Member
There sure is but I'd expect such a critical part would have been ultrasound tested for voids or any delamination hotspots.
Actually, reading 2hats' description again it seems to suggest that the voids between the composite wrap and the lining occurred after buckling of the lining, which could point towards a mechaical stress failure just as well as a manufacturing or material issues.
Actually, reading 2hats' description again it seems to suggest that the voids between the composite wrap and the lining occurred after buckling of the lining, which could point towards a mechaical stress failure just as well as a manufacturing or material issues.
2hats
Dust.
The SpaceX anomaly report isn't completely clear on the fine details.
Does their QA let vessels out of the factory with buckles in? I don't know, but more likely (I'm guessing) the liner debonded from the overwrap during cryogenic loading due to thermal stress because they are talking about loading with (relatively) warmer helium in future. (Or perhaps the bonding had been weakened during earlier pressurisation tests and in such future circumstances they don't want to aggravate it to failure).
Does their QA let vessels out of the factory with buckles in? I don't know, but more likely (I'm guessing) the liner debonded from the overwrap during cryogenic loading due to thermal stress because they are talking about loading with (relatively) warmer helium in future. (Or perhaps the bonding had been weakened during earlier pressurisation tests and in such future circumstances they don't want to aggravate it to failure).
pocketscience
Well-Known Member
Obviously a slightly more relaxed assessment by the faa for an unmanned space craft than it would have been for your average civil aviation event.
weltweit
Well-Known Member
Looks like the launch went to plan.
Did you get a good view?
I had a good view but was screwing about with my cameras too much to get really good shots. Fantastic atmosphere. There was easily 5000 people there. 2-3 miles of cars on both sides of the approach road. The noise was phenomenal given that we were four miles form the pad. There was a bit of a countdown, then a bit a pause because there was a ridge between the road and the pad. Someone shouted 'There it is!' as it crested the ridge. I was surprised how bright the exhaust flare was, then the noise hit us , a really loud vibrating roar. It passed though a layer where there was some condensation around the exhaust and then it was just a small bright dot as it carried on. I was also surprised how long I could still hear it, especially given how bad my hearing is. I saw it until MEKO, separation and second stage ignition, but others were saying that they could see the re-entry burn too.
On the way back to the car, some folks had the live stream wired to a speaker and I heard the moments up to the landing. Lots of cheering, smiles and high-fives. Fantastic atmosphere.
I'll work out how to post up a couple of shots tomorrow, a bit knackered (but very happy) at the moment!
On the way back to the car, some folks had the live stream wired to a speaker and I heard the moments up to the landing. Lots of cheering, smiles and high-fives. Fantastic atmosphere.
I'll work out how to post up a couple of shots tomorrow, a bit knackered (but very happy) at the moment!
Mumbles274
running from law and the press and the parents
+1 for photos
existentialist
Tired and unemotional
Ah. Permissions.
DotCommunist
So many particulars. So many questions.
upload direct using the 'upload a file' button next to 'post reply'
simplest way really.
