Live data from Hacker News

SpaceX SN9 Explodes on Landing

twitter.com

311–317 of 317 posts

Re: SpaceX SN9 Explodes on Landing

#311

Earlier quoted context omitted.

It’s really a throwback to the old days of aerospace. From the 1930s to the early 1960s, the standard method was to iterate rapidly with relatively cheap hardware, to learn and fix problems as quickly as possible. The von Braun and Korolev teams operated this way, among others. They all blew up a ton of rockets. What changed was the necessity of completing Saturn V and landing on the Moon by the end of the 1960s. Apo…

I’m not sure 3200 full scale tests of Saturn V’s F-1 engine, 2000 in an iterative trial-and-error scramble to suppress combustion instabilities is what I would call “overengineered to cut out iteration” during Apollo http://www.yang.gatech.edu/publications/Journal/JPP%20(1993,...

There was of course a ton of testing at the component level, and iteration when necessary. This worked for Saturn V because it could be done for each component in parallel, due to the huge mid-sixties spike in funding. But at the level of the integrated system, most of the testing—and nearly all of the iteration—was cut out, since it would have to be done in series for the entire rocket (or its stages). Thus the design had to be set in stone before the vehicle ever flew. The first and second stages of Saturn V flew just twice before crewed flight began. This was the right process for Apollo’s unique set of requirements and resources, but it is a bad idea when you A) don’t have a hard deadline forcing you to forego system-level iteration and B) don’t have a spike in funding to accelerate the up-front development, which otherwise takes forever. Hence SLS.

Re: SpaceX SN9 Explodes on Landing

#312

Earlier quoted context omitted.

I loved the explosion. These guys get stuff done. Move fast and break things

It should not have been an experiment leading to explosion at this stage. You are not seriously willing to justify the explosion, are you? I hope that you are being sarcastic. The experimental flying of rockets of this size are the 1960s thing. They should have acquired proper specs by now.

It’s been a few days and other people above have already put you through the ringer on this, but funny enough the 1960’s work style, of the soviets specifically, is ideal for rapidly advancing rocket tech. Or any tech, for that matter! They iterated and flight tested early and often. The soviets only lost the space race because they ran out of resources, as this is an expensive approach, but SpaceX is back-stopped by Elon + the US gov via contracts + they already have production flight revenue and wildly successful products.

I won’t be able to do the explanation much justice in a paragraph here but Google around about how the Soviet approach to rocketry was far superior than that of the US and you’ll uncover plenty on the topic. SpaceX is executing that same style of engineering development, marrying the ‘move fast and break things’ tech company ethos with aerospace engineering.

That’s why they’re so revolutionary: aero is typically riddled with red tape and risk aversion... they take the Silicon Valley approach of moving fast and breaking things, along with keeping as much engineering in-house as possible to cut down on expenditure, lead time, quality control etc. etc.

Source: used to work on SpaceX’s only commercial crew capsule competitor, Boeing’s Starliner, down at the Kennedy Space Center.

Re: SpaceX SN9 Explodes on Landing

#313

Earlier quoted context omitted.

I’m not sure 3200 full scale tests of Saturn V’s F-1 engine, 2000 in an iterative trial-and-error scramble to suppress combustion instabilities is what I would call “overengineered to cut out iteration” during Apollo http://www.yang.gatech.edu/publications/Journal/JPP%20(1993,...

There was of course a ton of testing at the component level, and iteration when necessary. This worked for Saturn V because it could be done for each component in parallel, due to the huge mid-sixties spike in funding. But at the level of the integrated system, most of the testing—and nearly all of the iteration—was cut out, since it would have to be done in series for the entire rocket (or its stages). Thus the desi…

Granted, I am biased towards propulsion, but we are not talking about some bolt or bearing as a 'single component'. The propulsion system is a complex thermodynamic cycle, with tanks, turbopumps, preburner, regenerative cooling, injection, engine, nozzle, etc. Seems to be a rather involved 'component'.

Re: SpaceX SN9 Explodes on Landing

#314

Earlier quoted context omitted.

It's not moving to goalposts to acknowledge that the USSR beat us to space and that a large part of their collapse was due directly to the influence of the US.

On the contrary: It was Western technology and capital that propped up the USSR despite its repeated failures and inefficiencies. https://capx.co/soviet-communism-was-dependent-on-western-te...

Lol, who beat Nazi Germany? Western technology or Soviet tech?

Re: SpaceX SN9 Explodes on Landing

#315
post #293

Earlier quoted context omitted.

It's not moving to goalposts to acknowledge that the USSR beat us to space and that a large part of their collapse was due directly to the influence of the US.

Upthread there was a claim by evgen that the way the US vs Soviet approach to the space race had been characterised by mempko was incorrect, and that the current safety of the Soyuz was (at least in part) paid for with the lives of cosmonauts. You go on to state that Russia beat the US into space (which is a non-sequitur), and later expand that "The USSR, had it not had to fight a cold war against the US, could very…

Part you aren't answering the question directly. Did the US not persecute communists? Has the US not directly been involved in wars in communist countries that have led to millions of deaths, both military and civilians? You say the USSR killed its people, yet you won't admit those people were leaving because they wanted apparently to go to capitalist societies. What happens if capitalist societies don't exist? Where are those people going to? Or was the USSR killing people just to kill people as you claim?

Re: SpaceX SN9 Explodes on Landing

#316
post #293

Earlier quoted context omitted.

Upthread there was a claim by evgen that the way the US vs Soviet approach to the space race had been characterised by mempko was incorrect, and that the current safety of the Soyuz was (at least in part) paid for with the lives of cosmonauts. You go on to state that Russia beat the US into space (which is a non-sequitur), and later expand that "The USSR, had it not had to fight a cold war against the US, could very…

Part you aren't answering the question directly. Did the US not persecute communists? Has the US not directly been involved in wars in communist countries that have led to millions of deaths, both military and civilians? You say the USSR killed its people, yet you won't admit those people were leaving because they wanted apparently to go to capitalist societies. What happens if capitalist societies don't exist? Where…

Of course you're right. USA has been continually at war, grinding the lives of brown people into profits for rich bastards, since before independence from Britain. Lots of Americans moved to USSR, especially non-whites. Truman had four years in which Stalin would have been happy to sign away nuclear weapons forever, but instead he was led by the nose by the armaments manufacturers and kept creating ever-more-deadly nukes. USSR continually tried to rein in communists in other nations in order to try to preserve peace, but was painted as a great instigator by the airtight propaganda that we Americans choke in from our births.

Still, it would have been better not to restrict emigration. That was not humane, and betrayed an antiquated view of how the world works.

Re: SpaceX SN9 Explodes on Landing

#317

Earlier quoted context omitted.

On the contrary: It was Western technology and capital that propped up the USSR despite its repeated failures and inefficiencies. https://capx.co/soviet-communism-was-dependent-on-western-te...

Lol, who beat Nazi Germany? Western technology or Soviet tech?

FDR supplied the Soviet Union with lots of Western tech, including aircraft.
Post reply on HN