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Starship's Third Flight Test [video]

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211–220 of 413 posts

Re: Starship's Third Flight Test [video]

#211

Earlier quoted context omitted.

They can launch payloads that bring in revenue while working on that problem. There is a good chance they put a bunch of Starlinks on the next flight.

They might do one to test deployment, but it'd be a throwaway. Their relight test was skipped (not said why), so they still don't have confirmation they can control where Starship re-eneters. Until that happens, it's very unlikely they'll target actual orbital velocity. The Starlink satellites do have thrusters, but they're ion engines, so not nearly enough thrust to get that last bit into orbit before they'd re-ente…

As long as it is profitable when thrown away, the math works. Remember, until Falcon 9, they were always thrown away (except for Shuttle). Even if not profitable in the short term, the delta between cost and breakeven is an R&D expense.

Payload able to be delivered to orbit safely and insurable? Ship it. The more you do, the faster you get better.

Re: Starship's Third Flight Test [video]

#212
So FAA cleared SpaceX and then within a few days they completed their launch pretty successfully by all accounts. So does that mean SpaceX could have launched a while back with no issues and were just waiting on the FAA? Did the FAA literally just slow down progress?

Not a good look on the FAA, they should just let SpaceX do what it does at the speed they want. If they cannot add any value to this engagement, the least they can do is to not subtract value.

Re: Starship's Third Flight Test [video]

#213

Earlier quoted context omitted.

Exactly, they’ve reached feature parity with large expendable launch systems so they can piggyback paying customers with a high risk threshold (starlink) on flights they’d be doing anyways. Given their cadence this phase won’t last long, they’ll likely achieve at least one successful landing next flight.

They have also been eager to launch version 2.0 starlink satellites, but they don't fit in the falcon fairing. The first couple batches of those would be test articles as well, so I'd be surprised if the next starship launch doesn't a few on board.

They've been launching a version of the v2 sats that do fit in the Falcon 9 fairing and supposedly have all the functionality of the larger versions. The issue is that F9 can only carry ~24 of those at a time, which slows down the pace of expansion a lot.

Re: Starship's Third Flight Test [video]

#214
post #72
post #9

I was just watching Spacex official stream and at ignition they switched to Musk hawking cryptocurrency. What just happened?? edit: wild I just realized take off is 50 minutes from now... what had I been watching?? they did a countdown and there was ignition... was that a time wrap? Am I going insane? edit2: @spacex034 is not @spacex... today I learned...

this is probably exactly why x started doing video. youtube is so full of fake channels that it readily presents fake ones at the top of search results. the x stream has been great and had a far greater reach (2.5 million) than any of the youtube streams by a factor of 10x or so.

NSF had 1.5M views on their stream, Everyday Astronaut had 1.8M views.

Re: Starship's Third Flight Test [video]

#215
post #67

Earlier quoted context omitted.

I guess they didn’t want to make it too easy for some Chinese fishing vessels ;)

Chinese fishing vessels in the Gulf of Mexico?

Some species are rare. You need to look in the right places if you want to catch some fine raptors.

Re: Starship's Third Flight Test [video]

#217
post #197

Earlier quoted context omitted.

They might do one to test deployment, but it'd be a throwaway. Their relight test was skipped (not said why), so they still don't have confirmation they can control where Starship re-eneters. Until that happens, it's very unlikely they'll target actual orbital velocity. The Starlink satellites do have thrusters, but they're ion engines, so not nearly enough thrust to get that last bit into orbit before they'd re-ente…

99% chance that they lost attitude control hence couldn't point the business end towards wherever they wanted to. we know they can relight the engine on the booster and we know they can relight for landing burns. no surprise if the next launch has a couple pre-production big starlink birds.

> know they can relight the engine on the booster and we know they can relight for landing burns.

Do we know that? Booster crashed into the water at full speed; landing reignition failed.

Re: Starship's Third Flight Test [video]

#218
post #196
post #184

Earlier quoted context omitted.

One technical modification: They need engine relight in orbit to work to deliver payloads, otherwise Starship will stay in orbit and they can not test reentry.

You need a second burn just to enter orbit. You burn at the top of the sub-orbital arc (opposite side of the earth) to enter orbit.

No, that's inefficient and real spacecraft don't do that for typical low earth orbits. Works in Kerbal Space Program, though.

Normal orbital insertion is a single burn to orbit (with staging). With the correct initial roll and pitch, the spacecraft follows a perfect gravity turn and ends up in a near circular orbit at main engine cut off.

Re: Starship's Third Flight Test [video]

#219
post #197

Earlier quoted context omitted.

99% chance that they lost attitude control hence couldn't point the business end towards wherever they wanted to. we know they can relight the engine on the booster and we know they can relight for landing burns. no surprise if the next launch has a couple pre-production big starlink birds.

On the contrary, they absolutely had attitude control. Otherwise reentry would have seen the ship tumbling out of control and quickly breaking up. Instead, SpaceX was able to begin a controlled reentry in the upright position, indicating nominal orientation performance.

My bet on the re-entry failure is that they have really poor attitude control. They definitely had some, but you can also see at different points that the plasma was shifting directions. At T+46, it was doing a spin as the first plasma started to show. At T+47, it was going down on the edge of the heat shields. At T+47:40 it appears to be going down engine first.

Moreover, I'm guessing the reason they skipped the mock re-entry burn was due to not being able to settle the propellant. Though it's really hard to tell if the turning of the Starship was to rotate which side was getting heating from the sun, or if it was spinning out of (or with less than desired) control.

Tim Todd noticed that the gas thrusters were icing over and then releasing the ice. So it's a reasonable guess that this was part of the issue, but that's leaning even more into speculation territory.

Re: Starship's Third Flight Test [video]

#220

I was surprised that during the initial ascent footage from the fin-cam, you can see that the grid fins are out. Do they not fold back on ascent? Or possibly drag on one side to arc over? Just seems weird to have your “drag device” deployed during ascent.

Grid fins aren't drag devices. They are control surfaces. As long as they are oriented so the fins are aligned with the airflow, they have no effect on orientation. The benefit of not folding them in is one less part that can fail. There might be a slight reduction in drag by folding them in, but not much and apparently not worth it.

The side edge of the grid fin may have more surface area than edge on.
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