Thunderf00t does another videos, looking at the audio from the explosion.
He makes a good point about that popping sound. Especially in light of this:
At this stage of the investigation, preliminary review of the data and debris suggests that a large breach in the cryogenic helium system of the second stage liquid oxygen tank took place. [Updated 09/24: At this time, the cause of the potential breach remains unknown.] All plausible causes are being tracked in an extensive fault tree and carefully investigated. Through the fault tree and data review process, we have exonerated any connection with last year’s CRS-7 mishap.
The popping sound is telling. That is a pressure vessel breach. Likely what happened is that the liquid Helium wanted for some reason to become gas. When this happens, the liquid HE wants to become the 1000 times less dense gas. This happens very fast and there are no rupture systems that are fast enough. The 6000 PSI mentioned was the normal operating pressure. There’s a good chance that the pressure at rupture was ten times that, and the event was not going to be over until all the gas vaporized. Which it did, taking the liquid O2 with it. There is no exact science to pressure vessels and even thought the technology is very mature, they still fail for unexplained reasons. A mild thermal stress between the 4k liquid HE and the approx. 100k LO2 might have been enough. Or there was a void in the composite tank. Or even a broken fiber. At this point there’s no easy way to tell. Well nobody was hurt and the satellite was insured, so the best thing to do is go on. Learn what you can from the wreckage, but understanding that there are never any perfect engineering answers.
In these days of GPS and jet aircraft it’s hard to believe how short a time it was that an around the world journey was an adventure rather than a matter of connecting flights, yet in 1929, that’s exactly what it was. Here’s a great documentary about the around the world trip.
He has a rather snarky take on the anomaly and frankly I think he went a little overboard. He’s right that NASA hasn’t had a ground based failure since the old Atlas days. So far until this happened SpaceX hadn’t had any fueling issues either. So I don’t think that SpaceX is as incompetent as Thunderf00t seems to think that they are.
When the space program was started back in the beginning of the 1960’s how to guide the spacecraft in space was a complete unknown. The problem of calculating burns and orbital insertions was a nontrivial one. At the time all flight control had been analog and in 1960, the computers filled up buildings. When the call came to go to the moon, one thing was clear though. A computer small enough to fit on the spacecraft was going to be essential. That computer would be the Apollo Guidance Computer(AGC).
When people first started to fly, an important question emerged. The question was “which way was up?” That seems like and easy question to answer, but when you are flying around in an airplane in a fog, it becomes more complicated. Here’s what aircraft in the early days of flight looked like.
These shows are where airplane geeks get to see all the latest things that fly and where engineers can get together and see the latest stuff. The size of the combined deals every year rivals the GDP of a fairly large country. So these shows are a big deal for the aircraft, parts and supplies manufacturers. When I was in the industry I just missed the Shows by not being in the right job at the time.
It’s also where there have been more than normal amount of very expensive accidents as the companies try to show what there stuff can REALLY do.
The aerospike engine was to be used first on the x33 Venture Star, an attempt to gather information leading to a true reusable Single Stage To Orbit(SSTO) vehicle. Unfortunately the X33 died because of mission creep and cost overruns. Essentially the mission planner forgot what the X projects were for and tried for a fully flight ready vehicle when what was needed was an engine test bed. They truly forgot the KISS principle in design and development.
Turning and turning in the widening gyre | The falcon cannot hear the falconer | Things fall apart; the centre cannot hold | Mere anarchy is loosed upon the world | The blood-dimmed tide is loosed, and everywhere | The ceremony of innocence is drowned | The best lack all conviction, while the worst | Are full of passionate intensity. -- W.B. Yeats, The Second Coming