“local structure anomaly”?
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China’s National Space Administration has figured out why its Long March Y2 launch went awry in July 2017. The “unsuccessful” launch, as Chinese authorities put it at the time, was China’s second attempt at achieving heavy lift capability with its new Long March 5 vehicle. The first launch of the rocket, which boasts a …
The fuel turbo pump lost a blade (“local structure anomaly”) that then dropped the fuel flow into the engine (“momentary decline”) causing an oxygen rich engine environment followed by rapid disassembly of the vehicle (“the loss of launch mission")
There was no recovery from the decline as the engine was now a firework.. And who said you needed black powder to do fireworks...
part of the problem may be the use of H2 rather than kerosene. The Saturn V first stage used kerosene but all other stages used liquid H2.
As I recall some of the problems with using liquid H2 in the first stage has to do with the fact that it's at an extremely low temperature, which causes material problems. Metals get brittle at cryo temperatures, and lubricants "don't". It's not so bad when you're operating in a vacuum or near vacuum, at least as I understand it, but at sea level you have moisture accumulation and the engine nozzle is somewhat of a compromise since it has to operate at atmospheric pressure as well as a near vacuum, and everyplace in between.
To get fuel into the engine at the necessary volume and pressure, you need to have a high volumetric flow turbine-powered pump. And apparently that's what broke. I think they use reaction-style turbines.
Anyway, my understanding is "it's tricksy" and Elon avoided it in the 1st stage, deliberately. And so did NASA back in the 60's. Probably for the same reasons.
I would guess the fuel tanks would be smaller as well, though the 1st stage would weigh quite a bit more when fully fueled, using kerosene rather than liquid H2.
They eventually developed them to the point where nothing physically cracked during the necessary burn time. But I do recall a Vulcain nozzle distorting and causing the changed thrust axis to push the Ariane off course and it failed to reach orbit.
When the Russians were developing the oxygen-rich turbo-pump-exhaust closed-cycle engines they had a few failures. Apparently when they went wrong the several inch thick steel turbo pump casings burned through in a few hundred milliseconds.
But it does give you about 40% more ummph than kerosene.
It's main disadvantage of LH2 is that you can't store the fueled rocket for very long so it isn't much use a missile. If your launch technology is really just an ICBM offshoot or is just a cover for missile work then kerosene is a better choice
Did NASA fake the "giant leap" event to continue funding ?
Apollo Command Module had inadequate fuel for return flight. Lander Module had inadequate fuel for landing and takeoff. NASA never had a successful robot land and return from Earth. There was no docking or air lock system on Command or Lander Modules.
CIA has a long history of film propaganda, TruthStreamMedia >
"Military Top Secret Hollywood Film Studio"
I reckon Bubba has it about right.
Also especially galling with the Indians having gotten to Lunar orbit first.
Note though that LH2 makes a lousy fuel for ICBM use, unlike hypergols, which served the US Titan 2 well for decades (and still fill the tanks of many of the Russian fleet).
I would take that as bad news. It seems that the moon mission is on hold, or at least severely set back.
Which is contradictory when China declares that the launcher's problems have been dealt with. If that is truly the case, then China should have given a new timeframe immediately, with enthusiasm.
But no. No more problems, and no moon launch timeframe. Those two things don't go together.
It doesn't look good.
I wouldn't be so hard on the Chinese. The American Space program was crap in the early years too. It also suffered big setbacks. There is even speculation that Russia may have even been the first country to lose a spaceship containing two cosmonauts back in the 1950's. In any case -- so long as the Chinese play nicely - they can visit the rabbit on the moon any time they want.
There were persistent rumours of earlier losses. Although, since stuff opened up in the 90s I'm pretty sure we'd have found out if they were actually true.
Radio 4 did a great documentary on a bunch of Italian radio hams in the 50s and 60s. They'd got an old WWII bunker and a bunch of radio kit and were having lots of fun listening into (and recording) US and Russian space comms.
But then they've got "other" recordings. For some reason they started faking stuff. There's a recording of a woman cosmonaut struggling to breathe (presumably g forces) and then dying - and another of a Russian crew whose retro burn has gone wrong and sent them on a one-way trip away from the Earth - as they chat to mission control before going out of radio range - and off to certain death.
Robert Heinlein mentions a manned launch (in the 60s I think) that was announced when he was in Moscow, on holiday. Then no further announcements were made about it, and there were rumours that it had blown up. But then he was very anti-Soviet and maybe wanted to believe that, and inconsistency and bizarre attacks of secrecy in Soviet media announcements wasn't exactly uncommon...
I've heard the "lost cosmonaut" theories, but as you point out, they're almost certainly bollocks. The USSR was surprisingly open about Komarov in Soyuz 1, and the three cosmonauts in Soyuz 11 (pretty much the only people to die in space AFAIK), so it's pretty unlikely they'd have covered up manned launches.
I think part of the stories might have come about because during test launches the Soviet engineers would test the air-ground radios by broadcasting from the test spacecraft, so radio hams might well have picked up transmissions from spacecraft that were officially unmanned.
"The American Space program was crap in the early years too. It also suffered big setbacks."
And they learned from them. One of the lessons being "don't trust contractors"
From the Earth to the Moon miniseries was pretty good at covering much of this.
One good example being the Apollo1 fire. Whilst the proximate cause of the disaster was too much velcro in a pressurised oxygen atmosphere (polyester is explosively flammable in that environment), when a capsule was torn down to see what started the fire it was found to be so shoddily built that the sparking wiring that triggered the fire was the least dangerous of the many faults which could have killed astronauts in orbit.
Quality control is important.
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