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Comment by physicles | Hacker News Reader

The fact that Ariane 5 was chosen to launch the $10 billion must-not-fail JWST says a lot about trust in the rocket. The particular rocket that launched Webb also got some extra TLC from the engineers:

> The Ariane 5 program also selected the best components for Webb based upon pre-flight testing. For example, for the Webb-designated rocket, the program used a main engine that had been especially precise during testing. "It was one of the best Vulcain engines that we've ever built," Albat said. "It has very precise performance. It would have been criminal not to do it."

From https://arstechnica.com/science/2022/01/all-hail-the-ariane-...

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Importantly the precision means the orbit of JWST needed less fuel to correct, leaving more for future corrections and extending the lifetime.

> The launch was described by NASA as "flawless" and "perfect".[4] A NASA systems engineer said “the efficiency or the accuracy with which Ariane put us on orbit and our accuracy and effectiveness in implementing our mid-course corrections” meant that there is “quite a bit of fuel margin ... roughly speaking, it’s around 20 years of propellant.”[16][17]

From https://en.m.wikipedia.org/wiki/Ariane_flight_VA256

When you have many satellites and want it cheap, go with SpaceX. If you have one priceless irreplaceable satellite hundreds of people spent decades building, go with Ariane. There is market for both.

I doubt achieving the same with SpaceX, especially given the amount of prep that went into this launch is somehow impossible. Perhaps has more to do that the launch vehicle was chosen before Falcon 9 has made its maiden flight.

This is the correct sentiment and although I absolutely love what SpaceX has acheived, whenever there is some news about a new (or old) rocket here on hn, here comes a bunch of folks stating that everybody should just stop everything they're doing and just hire SpaceX for everything forever. Very cultish imo.

This isn't really the case. The Ariane 5 was selected because ESA agree with NASA that ESA would pay for the launch. And of course ESA would use the Ariane 5.

Had NASA paid for the launch, both the Delta 4 (Heavy) and the Atlas 5 has the necessary NASA certification.

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