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It's pretty clear to me that SpaceX has no comprehensive model of how their craft works, or a clear testing methodology; they're just throwing stuff at the wall

It's pretty clear to me that SpaceX has no comprehensive model of how their craft works, or a clear testing methodology; they're just throwing stuff at the wall to see what sticks. They're going to be finding unfortunate surprises in the "Starship" until the day it is taken out of service. It reminds me of how the Space Shuttle was designed. Hope is not a strategy.

someperson 6y ago
SpaceX has a "test as you fly" philosophy. It's the same approach that built the Soviet Union's excellent rockets (including the Soyuz). Unlike the Soviet Union, SpaceX can afford to fund their version of the "N1" moon rocket: at around $1 million per Raptor engine (and 3 Raptors per Starship hop test) the R&D program is still relatively affordable, even with the failures. This philosophy is in stark contrast to the SLS (Space Launch System) which after decades of development has only just done a static fire. Also SpaceX's philosophy around the Starship test program is focused on building a factory that can manufacture thousands of Starships vehicles a year. But I agree on the spectrum between "analysis paralysis" and "reckless" SpaceX is arguably a bit too far towards reckless at the moment. I hope apparently wasteful R&D program yields better results soon. They need to start testing rapid reuse for Starship to be able to meet its cost goals.
- kazinator 6y ago
  https://www.npr.org/sections/krulwich/2011/05/02/134597833/cosmonaut-crashed-into-earth-crying-in-rage https://www.npr.org/sections/krulwich/2011/05/02/134597833/c...
  - avmich 6y ago
    Yeah, Komarov's story was a really bad example of rushing things. Looks like it helped to bring space industry leaders to senses. USSR was infamous for trying to make "victories" by the time of next anniversary of October Revolution, or party gathering, but spaceflights since then weren't rushed with half-baked tech and a human onboard.
lolthishuman 6y ago
You’re basing that off of what? Sounds like you’re just spreading FUD.
nuccy 6y ago
Well, obliviously they do have a comprehensive model since they are able to: 1. start the most advanced rocket engines (full-flow staged combustion cycle engines [1]) 2. ascend to 10km gradually shutting down (and throttling) engines to keep relatively constant speed while methane and oxygen are depleting 3. switch from vertical ascent to horizontal descent flight profile, and from 10km "fall" (or rather fall/glide) into the 30 meters target of the landing pad 4. reach soft landing (almost accomplished by the SN10) BTW Roughly only the first two of those items are in the "normal" checklist of any other rocket company for an orbital rocket. SpaceX is following somewhat Soviet rocket development approach with many testing, which is not a bad thing by itself. It is just different to what we are used with NASA/ULA/et al. SpaceX is also very open with their testing, you can literally see the rocket from 50 meters away, and its launch (from 8km) freely. We obviously have an observational bias here, while not knowing how many failures others have. [1] https://en.wikipedia.org/wiki/Staged_combustion_cycle#Full-flow_staged_combustion_cycle https://en.wikipedia.org/wiki/Staged_combustion_cycle#Full-f...
- HarryHirsch 6y ago
  start the most advanced rocket engines (full-flow staged combustion cycle engines [1]) Well, not. During SN9 flight, one engine could not be re-lit, so SN9 crash-landed. During SN10 flight, the two engines that were needed for landing were lit, but there was an imbalance in the fuel mixture, one engine burned noticeable more yellow than the other, and now this. You'd think they'd analyze telemetry data from flights and on-ground testing and improve their design, but visibly they don't. And they are on notice already from the FAA for routinely blowing stuff up near a populated area.
  - vardump 6y ago
    Wasn't SN11 already completed when SN10 failed? SpaceX has a production pipeline, they're working on multiple rockets in the same time. The lessons from SN9 and SN10 are probably incorporated SN20 or even later version. (Or corresponding versions of Raptor engines.)
  - PeterisP 6y ago
imglorp 6y ago
This is the same process that produced the F9, now up to some 115 flights, many reused and reflown. It's very hard to argue with success.
unethical_ban 6y ago
I disagree with this comment strongly, but I do not believe it is a deliberate troll or insult. It should not be flagged IMO.

someperson 6y ago

SpaceX has a "test as you fly" philosophy. It's the same approach that built the Soviet Union's excellent rockets (including the Soyuz). Unlike the Soviet Union, SpaceX can afford to fund their version of the "N1" moon rocket: at around $1 million per Raptor engine (and 3 Raptors per Starship hop test) the R&D program is still relatively affordable, even with the failures. This philosophy is in stark contrast to the SLS (Space Launch System) which after decades of development has only just done a static fire. Also SpaceX's philosophy around the Starship test program is focused on building a factory that can manufacture thousands of Starships vehicles a year. But I agree on the spectrum between "analysis paralysis" and "reckless" SpaceX is arguably a bit too far towards reckless at the moment. I hope apparently wasteful R&D program yields better results soon. They need to start testing rapid reuse for Starship to be able to meet its cost goals.

kazinator 6y ago
https://www.npr.org/sections/krulwich/2011/05/02/134597833/cosmonaut-crashed-into-earth-crying-in-rage https://www.npr.org/sections/krulwich/2011/05/02/134597833/c...
- avmich 6y ago
  Yeah, Komarov's story was a really bad example of rushing things. Looks like it helped to bring space industry leaders to senses. USSR was infamous for trying to make "victories" by the time of next anniversary of October Revolution, or party gathering, but spaceflights since then weren't rushed with half-baked tech and a human onboard.

lolthishuman 6y ago

You’re basing that off of what? Sounds like you’re just spreading FUD.

nuccy 6y ago

Well, obliviously they do have a comprehensive model since they are able to: 1. start the most advanced rocket engines (full-flow staged combustion cycle engines [1]) 2. ascend to 10km gradually shutting down (and throttling) engines to keep relatively constant speed while methane and oxygen are depleting 3. switch from vertical ascent to horizontal descent flight profile, and from 10km "fall" (or rather fall/glide) into the 30 meters target of the landing pad 4. reach soft landing (almost accomplished by the SN10) BTW Roughly only the first two of those items are in the "normal" checklist of any other rocket company for an orbital rocket. SpaceX is following somewhat Soviet rocket development approach with many testing, which is not a bad thing by itself. It is just different to what we are used with NASA/ULA/et al. SpaceX is also very open with their testing, you can literally see the rocket from 50 meters away, and its launch (from 8km) freely. We obviously have an observational bias here, while not knowing how many failures others have. [1] https://en.wikipedia.org/wiki/Staged_combustion_cycle#Full-flow_staged_combustion_cycle https://en.wikipedia.org/wiki/Staged_combustion_cycle#Full-f...

HarryHirsch 6y ago
start the most advanced rocket engines (full-flow staged combustion cycle engines [1]) Well, not. During SN9 flight, one engine could not be re-lit, so SN9 crash-landed. During SN10 flight, the two engines that were needed for landing were lit, but there was an imbalance in the fuel mixture, one engine burned noticeable more yellow than the other, and now this. You'd think they'd analyze telemetry data from flights and on-ground testing and improve their design, but visibly they don't. And they are on notice already from the FAA for routinely blowing stuff up near a populated area.
- vardump 6y ago
  Wasn't SN11 already completed when SN10 failed? SpaceX has a production pipeline, they're working on multiple rockets in the same time. The lessons from SN9 and SN10 are probably incorporated SN20 or even later version. (Or corresponding versions of Raptor engines.)
- PeterisP 6y ago

imglorp 6y ago

This is the same process that produced the F9, now up to some 115 flights, many reused and reflown. It's very hard to argue with success.

unethical_ban 6y ago

I disagree with this comment strongly, but I do not believe it is a deliberate troll or insult. It should not be flagged IMO.