someone [comrade/them, they/them]

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Joined 6 months ago
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Cake day: January 11th, 2024

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  • That is a really bizarre structural failure of the test rig. I’m been a space nerd for my entire life and I’ve never seen footage like this. For this rocket to lift off vertically, all the mechanisms holding it down had to have failed simultaneously. If they failed at different times it should have gone wildly off-course from the start. That simultaneous failure is statistically unlikely to say the least. I’m wondering if it wasn’t mechanical failure, but a failure of the control system managing the hold-down mechanisms.

    For comparison, here’s what a Falcon 9 static fire looks like. They don’t just use the normal launch clamps at the base of the rocket, they also have a heavy cap on top (the orange part) with a cable rig system anchoring it down to make damn sure it doesn’t go anywhere. They run all systems of a production rocket at the full thrust and full duration of an actual launch to test everything as a unit.






  • In fairness this could have been a purely technical decision and not a political one. The Falcon 9 does have an excellent track record in performance and safety. Falcon 9’s only launch failure was in 2015, using a long-obsolete variant. It’s had over 330 successful launches since then, most of which were the current final variant. Ariane 6 has never yet launched, and new-design Ariane rockets have historically had teething issues. For example, the Ariane 5’s first launch failed because it was using guidance software that was almost unchanged from the prior Ariane 4, despite being aerodynamically a very different vehicle. I’m wondering if Eumetsat’s engineers don’t like what they’re seeing in the Ariane 6, which is due to fly for the first time in two weeks and is many years late in development.

    It’s an interesting time in spaceflight. Several new unproven rockets becoming available (Vulcan-Centaur, Ariane 6, New Glenn). Several proven rockets no longer available as they’re being retired or are already retired (Delta IV, Atlas V, Ariane 5). European agencies looking to launch heavy satellites just don’t have many options if they’re legally constrained from launching on Chinese or Russian vehicles. Falcon 9 may have literally been the only alternative that met Eumetsat’s legal and engineering requirements.

    A side rant, because where else am I going to rant about Ariane 6’s design? I’ve always been disappointed by ArianeGroup’s choice of using solid-fuel boosters in the Ariane 6 instead of going with kerosene or methane fueled engines that are powerful enough to not require booster rockets. Hydrogen engines are typically very fuel efficient, and they burn clean. The only exhaust is water, there’s no carbon chains that can clog engines. This translates to reliability for multiple engine ignitions while in space. That fuel efficiency and re-ignition reliability are both very useful traits in upper-stage engines where pure power isn’t needed. But hydrogen fueled engines are usually not very powerful and often need boosters just to get off the ground. That’s why the space shuttle had to augment its three hydrogen fueled main engines with two big solid-fuel boosters. It’s unfortunately unsurprising, as it’s also France’s way of quietly subsidizing development of their submarine-launched nuclear missiles through ESA funds. Those missiles are heavily based on P80/P120/Vega solid-fuel rocket technology. The US isn’t the only country out there that’s shackled its space exploration efforts to its for-profit defence contractors.