Author Topic: Starship!  (Read 58769 times)

Offline raven

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Re: Starship!
« Reply #210 on: May 07, 2021, 01:34:59 AM »
Definitely a giant leap. I am sure they will work out the kinks in the next steps.

Like the video downlink?  ;)
Yeah, that would be nice, especially when they insist on flying in fog or lowish cloud cover.

Offline jfb

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Re: Starship!
« Reply #211 on: August 09, 2021, 01:58:28 PM »
Tim Dodd, the Everyday Astronaut, scored a walkthrough of the Boca Chica site with Elon Musk as the tour guide.  The interview is over two hours long, so Dodd has broken it up into multiple segments, of which the first two have dropped:

Part 1
Part 2

Part 3 hasn't dropped yet, but that will be at the pad.

Elon talks about his engineering philosophy in Part 1, which in order is basically:

  • Make your requirements less dumb.  All requirements are dumb, make yours less dumb.  Beware of requirements given to you by a smart person, because you're less likely to question them.
  • Aggressively delete unneeded parts and process steps (the best process is no process, the best part is no part).  If you're not having to go back and add parts or steps back in later, you're not being aggressive enough in deleting anything that's really unnecessary.
  • Optimize and/or simplify.
  • Reduce cycle time.
  • Automate.

Anyway, cool interview.  A lot of stuff is still in flux and they're still changing parts of the design as they go.  Everything is still too heavy and needs trimming.  The primary goal for the orbital test flight is to not take out the launch pad (a.k.a. Stage 0).  The first few orbital ship prototypes are just meant to get to orbit, deorbit, and land - none of them will carry any payloads, so they're not worried about doors or payload bays yet. 

Offline Obviousman

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Re: Starship!
« Reply #212 on: August 09, 2021, 04:27:41 PM »
That philosphy seems good to me.

Requirements... phew! I fight a regular battle of trying to get requirements from my people. Instead, they tell me what they want and when we give it to them, they say "That is exactly what we asked for. But it is not what we want".

Offline Peter B

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Re: Starship!
« Reply #213 on: August 09, 2021, 07:19:23 PM »
That philosphy seems good to me.

Requirements... phew! I fight a regular battle of trying to get requirements from my people. Instead, they tell me what they want and when we give it to them, they say "That is exactly what we asked for. But it is not what we want".

I can see where you're coming from, but I've been at the other end of the stick. Or, more precisely, I've been an inadvertent customer for a product someone else designed for another customer, but I have to use the product without having had any say in the design. So for me it would be more like, "We didn't ask for this, and it's not what we want."

And I'd humbly suggest that's how it works in most of the world - products are rarely for a single customer, so an important part of the design process is should be working out who the customers really are and engaging all of them (to a realistic extent) in the design process.

A friend told me about a job request system which was introduced in his workplace. He was in a customer service area, so clients would use this JR system to ask for work to be done. Logically, the customers for this product would be the work area and the clients. But instead the customers were Management. They got exactly what they wanted - a cheap system with a reasonable suite of reports so they could check up on the efficiency of the work area. The clients got an unhelpful interface which made it slow to log requests. And the work area got a clumsy system which listed jobs in an order which was neither alphabetical or chronological, and so slowed down their work and annoyed clients because of the seemingly random order they completed job requests.

Offline jfb

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Re: Starship!
« Reply #214 on: August 10, 2021, 03:58:39 PM »
Yeah.  My group used to be part of a much larger organization, and we were kind of the red-headed stepchild.  Our product is an online banking platform geared towards smaller community banks and credit unions, while the mothership was a payment processor.  All the processes and forms worked well for the payment-processing world, but were overly complex and tedious for our purposes.  Change requests required a two-week lead time, had to be approved at the VP level, and all kinds of other nonsense. 

Once we were spun off into our own company, we were able to adopt a much leaner process, such that we only need a day's lead time for CRs, and it's a lot easier to keep track of tickets. 

Offline Obviousman

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Re: Starship!
« Reply #215 on: August 10, 2021, 05:18:12 PM »
Ha! So much of this resonates with me.

These days I am a Defence contractor and manage a USAF-owned software system called Patriot Excalibur, or PEX. It's an aviation resource management system. It's used by every flying unit in the USAF, as well as the majority of other USAF units. Since it has such a wide user base, it has to cater to many different types of operation (fighters, tankers, bombers, transport, etc), each with specific requirements. The system does this quite well, offering various options for each module to suit the user need.

We decided to use it in Australia since it was a good tool. Even then, we still had to make modifications to suit the Australian environment. Despite being a good tool, there are areas where the users complain and want changed. Command also uses PEX but mainly in the area of data mining, rather than flight scheduling / flying currency management.

So we have a fair few bugs / enhancements to address. We used to do this with Agile development, putting out a new release every 3 months but now we are shackled to Defence's processes, it takes us 6 months to generate the required paperwork for a release.

Still, not too bad, eh? Nope. The person in charge of the system for one of the Services stymies us. They are a very smart individual but have never been in uniform, have never been aircrew. And more often than not, we have suggestions for improvement to which the frontline workers say "Fantastic! Just what we want! When can we have it?" and this person says "They don't need that" and instead lobbies for some reporting tool, which is wanted only by a small group but is usually Command.

No wonder I am retiring!

[END RANT]

Offline Peter B

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Re: Starship!
« Reply #216 on: August 11, 2021, 03:41:40 AM »
Ha! So much of this resonates with me.

...

So we have a fair few bugs / enhancements to address. We used to do this with Agile development, putting out a new release every 3 months but now we are shackled to Defence's processes, it takes us 6 months to generate the required paperwork for a release.

...

[END RANT]

6 months?

Sheer looxury!

My friend said his system has shortcomings which haven't been addressed in 20 years...

Offline Peter B

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Re: Starship!
« Reply #217 on: August 11, 2021, 05:35:15 AM »
Having said all that, the video of the fully stacked starship was pretty impressive. The idea that it could be being launched within a year equally so.

Offline JayUtah

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Re: Starship!
« Reply #218 on: August 11, 2021, 09:45:43 AM »
I know for a fact that the Starliner folks are looking at SpaceX with a fair amount of envy right now -- not necessarily for the technology differences, but for the differences in development posture.  Government-supervised development contracts mean a lot of overhead and oversight that SpaceX simply doesn't have to deal with for Starship.  Musk isn't saying anything that other engineers don't already know.  It's just that -- as many others of you have pointed out -- the pace at which you can do them and the decision to undertake them take so much more time when contractual strings are attached.
"Facts are stubborn things." --John Adams

Offline Ranb

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Re: Starship!
« Reply #219 on: September 25, 2021, 08:56:48 PM »
Dump question time, sorry if this was addressed before. 

How is the Starship expected to remain upright when landing on the moon?  The Apollo LEM was 23 feet tall and 31 feet wide with the legs extended.  The Starship is 394 feet tall and only 30 feet wide.  Seems rather tippy.  I think it is likely to fall over on all but the most even ground; am I missing something.

Offline Peter B

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Re: Starship!
« Reply #220 on: September 25, 2021, 10:41:01 PM »
Dump question time, sorry if this was addressed before. 

How is the Starship expected to remain upright when landing on the moon?  The Apollo LEM was 23 feet tall and 31 feet wide with the legs extended.  The Starship is 394 feet tall and only 30 feet wide.  Seems rather tippy.  I think it is likely to fall over on all but the most even ground; am I missing something.

Oh, that's easy - it's just like how They filmed Armstrong's first steps on the Moon: where one of the astronauts got out first to set up a camera. So with Starship, it'll deploy a flattened landing platform first, and then land on it. Simples!

*/Dunning-Kruger*

Seriously, good question, and I haven't seen it addressed (which is not to say it hasn't been addressed).

The first thought that comes to mind is that SpaceX seems to be able to land its Falcon 9 boosters incredibly accurately. So, once they've identified a landing place on the Moon I suspect they'll have little difficulty landing Starship within a couple of metres of their target point.

That suggests to me two alternatives. First option is that they use the highest quality images of the surface to generate 3-D maps to identify safe landing locations. Second option is that they adapt an Artemis lunar lander to place a mobile device on the surface to actively level an area into a landing site.

Having said all that, while Starship is tall, is it necessarily tippy? I mean, there will be fuel in the bottom of the tanks, and the engines themselves are fairly massy. So even if there are crew quarters and human cargo up top, won't the centre of mass still be fairly low?

Offline Ranb

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Re: Starship!
« Reply #221 on: September 25, 2021, 11:39:50 PM »
If the lunar (or Martian) surface was uniformly solid and without any dust covering a boulder or crater, I suppose it would not be a big deal to locate a flat surface during the landing sequence. 

But even the Falcon-9 has landing gear that extends out to a ten meter diameter to land on a flat stable barge in the ocean. 

With Starship it seems as comically strange as the old artist renderings of "V-2 looking" rockets landing on the moon.

Offline Glom

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Re: Starship!
« Reply #222 on: September 26, 2021, 10:58:44 AM »
Maybe the legs are adjustable? Working out the topography on the fly and adjusting how each leg deploys would be not too difficult?

Offline smartcooky

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Re: Starship!
« Reply #223 on: September 26, 2021, 10:45:36 PM »
I follow the Reddit page r/spacex which often has tweets from Elon posted. He mentioned a some time ago that both the Moon & Mars lander legs would have legs and be self levelling to cope with slopes or soft patches found on landing.

I have seen two versions of Starship HLS with legs..


As far as I can tell, the version on the right is most recent, and appears to be what SpaceX are going with... at the moment. It matches the latest graphics from NASA & SpaceX on the award of the Lunar Lander contract, which show it with Apollo-LEM style legs and footpads.

Hard data is difficult to find, but from what I have been able to find out, the C of M for Starship with very low fuel and max payload to the moon is well below the midpoint, because those six Raptor engines at the flamey end are very heavy. It seems the maximum tilt is likely to be about 10°. Now that doesn't sound like a lot, but for some perspective.. this thing...



The Leaning Tower of Pisa, which is taller (186ft v 164ft) and weighs a lot more (16,000 tons v 1,300 tons) is currently leaning at an angle of 4° 

If you're not a scientist but you think you've destroyed the foundation of a vast scientific edifice with 10 minutes of Googling, you might want to consider the possibility that you're wrong.

Offline smartcooky

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Re: Starship!
« Reply #224 on: September 27, 2021, 02:35:32 AM »
Weird. My picture of Pisa Tower disappeared

Never mind, here is another one

If you're not a scientist but you think you've destroyed the foundation of a vast scientific edifice with 10 minutes of Googling, you might want to consider the possibility that you're wrong.