mfb- t1_j9x4851 wrote on February 25, 2023 at 4:42 AM

Reply to comment by DBDude in After Vulcan comes online, ULA plans to dramatically increase launch cadence by OutlandishnessOk2452

> The Raptor is doing fine

Most landing failures were linked to the engines not starting up properly. The recent static fire was done with 31/33 because two engines had issues. Compared to a landing this is less critical during a launch because of the large redundancy, but they clearly need to work on that for routine flights.

DBDude t1_j9yf6e0 wrote on February 25, 2023 at 2:06 PM

That was in testing. This thing does have a very complicated startup.

mfb- t1_j9ykv8u wrote on February 25, 2023 at 2:52 PM

The most recent test still had issues with two engines.

It's a complicated engine, but that doesn't mean issues are not issues any more.

DBDude t1_j9z1jov wrote on February 25, 2023 at 4:49 PM

My point is that the Soviets mastered this design almost 50 years ago, yet BO is having problems doing it just with a different fuel. Nobody's ever mastered full-flow staged combustion (didn't go beyond testing), yet SpaceX appears further along with that than BE-4, in about the same amount of time. My bet is that it's mostly management issues.

Edit: New news: ULA is having problems qualifying one of the engines for flight because it keeps pumping out too much oxygen. You'd think BO would at least have something like this right before they shipped, but apparently the engines had only minimal testing.

I like SpaceX, but I don't want them being the only cheap, reusable medium+ launch service out there. BO needs to get its act together.