SpaceX Starship - IFT-3 - Starbase TX - Launch Thread and Post Launch Discussion

Launch Date: March 14
Launch Window: 7:00 am CDT (9:00 am EST, 13:00 UTC)
Launch site: LC-1 - Starbase, Boca Chica Beach, Texas
Core Booster Recovery: Expended in Gulf with a landing burn
Starship Recovery: A controlled reentry through the atmosphere to a terminal velocity splashdown in the Indian Ocean
Booster: Super Heavy Booster 10
Starship: Starship 28
Mass: No mass simulator mentioned
Orbit: LEO-ish
Yearly Launch Number: 26

A SpaceX Super Heavy and Starship launch vehicle will launch on its third not quite orbital integrated flight test designated IFT-3. The mission will attempt to place Starship into a nearly orbital trajectory that will attempt a controlled reentry through the atmosphere to a terminal velocity splashdown in the Indian Ocean . The Super Heavy booster will attempt a landing burn in the the Gulf of Mexico where it will likely be destroyed. This is a further test of Stage 0, the booster, full power ascent, Max-Q, stage separation using the new hot staging, a booster stage test of a hard turn and boostback, full burn boost of Starship to space and sub LEO, Starship will do one partial orbit, simulate a de-orbit burn, test tiles and heating from atmospheric reentry, until it has a splashdown in the Indian Ocean.

It has also been determined that for this test flight there will be a fuel transfer test done on Starship for NASA's Tipping Part contract. The Starship will also test its payload bay door in zero-G for a test of future Starlink 2.0 deployments.

 

[mongo]

Do you think they intended to relight engines at 500 meters and perform a full braking burn? That would involve almost a 10 g suicide burn.

I don't think so, it looked like they started trying to light engines earlier but they didn't spool up. At 500 meters somebody really didn't want to...

I might have believed it if it was purely roll, but it was actually a slow tumble. How does a Starship perform attitude control? With the cowbell thrusters?

Yeah, tank vent thusters. Maybe it ran out of ullage gas?

 

[Electroman]

Is this coastline Madagascar ?

 

[JB47394]

Was this the first ever external video of reentry plasma? Pretty amazing.

Probably. The Shuttle would have been a prime candidate for that, but they couldn't see their wings out the windows. That was a contributing factor to the loss of the crew of Columbia.

Is this coastline Madagascar ?

I think it's cloud shadow. Continue forward with the video and you'll see the correlation between cloud and shadow. If you continue all the way to about 1:19:45, you get a good view of the Earth behind the ship. There might be land in there. Either Madagascar or the coast of Africa itself.

 

[mongo]

I think it's cloud shadow. Continue forward with the video and you'll see the correlation between cloud and shadow. If you continue all the way to about 1:19:45, you get a good view of the Earth behind the ship. There might be land in there. Either Madagascar or the coast of Africa itself.

Even here? Looks landish (or second cloud layer?)

 

[Pricee2]

Probably. The Shuttle would have been a prime candidate for that, but they couldn't see their wings out the windows. That was a contributing factor to the loss of the crew of Columbia.


I think it's cloud shadow. Continue forward with the video and you'll see the correlation between cloud and shadow. If you continue all the way to about 1:19:45, you get a good view of the Earth behind the ship. There might be land in there. Either Madagascar or the coast of Africa itself.

I was unclear in my question. I was meaning the camera was mounted externally so the view was from outside the spacecraft. There are views of the plasma from inside Dragon capsules.

 

[ecarfan]

Here’s something I don’t understand. At T+9:16 the graphic showing the ship orientation reverses direction in a fraction of a second. But the video stream does not show such a rotation.

 

[JB47394]

Even here? Looks landish

Definitely landish there. Now I see what @Electroman was referring to; it's tucked in under the clouds in his image. In the video, I can easily see it as it first comes into view at 1:18:13.

 

[mongo]

Here’s something I don’t understand. At T+9:16 the graphic showing the ship orientation reverses direction in a fraction of a second. But the video stream does not show such a rotation.

View attachment 1028028View attachment 1028029

Was it traveling sideways at that point? Could be a <> +/- 90 artifact...

 

[ggr]

So the booster grid fins looked like they were really working hard before the signal was lost.

And the ship engine relight was a success, and they said the payload door did open. All good news.

If there was a pilot, I'd have called the action of the grid fins "pilot induced oscillation".

I thought they skipped the ship engine re-light.

 

[JB47394]

I was unclear in my question. I was meaning the camera was mounted externally so the view was from outside the spacecraft. There are views of the plasma from inside Dragon capsules.

The camera is mounted in the flap. The flap is part of the vehicle. By that metric, it's "internal". shrug

I thought the more interesting question was whether there has ever been a third person view of a plasma piling up on a spacecraft surface such that you can see the surface and the plasma. That's why I mentioned the Shuttle. Few other spacecraft have concavities in their outer surface.

 

[ecarfan]

I thought they skipped the ship engine re-light.

Apologies, you are correct. Not sure why I got that so wrong…

 

[unk45]

Hello from a denizen from other TMC forums, such as the TSLA Investors Discussion thread,
and occasionally subthreads of "AI, Autopilot, & Autonomous/FSD". I was quite impressed
by the launch today, and now see noted that Pi Day marks the founding of SpaceX. This is
clearly the place which has the most Pi Day related posts, so please accept my humble but
geeky contribution.
______

I've been thinking about Tesla's "march of nines" highlighted in earnings calls and other presentations
since 2020, largely applicable to autonomous driving,

https://www.carswithcords.net/2020/07/tesla-and-long-march-of-nines-to-full.html

At first glance the reference seems fanciful, since in much engineering work we’re
happy with an improvement of 10%, let alone a bigger breakthru of 90%, or one “nine”.

The term is squishy, but it’s been referenced in other fields. E.g. in well-controlled
clinical drug trials, having a “p-value” of < 0.01 augurs good statistical significance —
that is “two nines”. In physics there is an “n-sigma” event. For the discovery of the
Higgs boson, a 5-sigma experiment corresponds to a p-value of 3 x 10 to the minus 7,
or about 1 in 3.5 million, or in between six and seven nines.

https://www.scientificamerican.com/blog/observations/five-sigmawhats-that/

Relevant to FSD, there’s an injury collision about once every million driving miles,
and a fatality about once per 100M miles, so six to eight nines. But if you are
talking about the percentage of Tesla drive time one might actually use FSD,
it’s lower. I’m somewhere between one and two nines right now.
_______

OK, so now an anecdote about the great physicist Richard Feynman, who
used the notion of six nines, 999999, in a humorous way. This has to do
with the number pi, so happy pi day, today, March 14 …

Because pi appears random (every digit statistically seems to occur equally
often, and further testing on multi-digit sequences hints at “normality”),
Feynman was struck by the fact that 999999 occurs at position 762 of pi’s
decimal expansion. Known as the “Feyman point”, joker Feynman wanted
to memorize pi to that point, reciting the digits in a lecture and then after 762
say, “… nine, nine, nine, nine, nine, nine, and so on…” implying that it would
repeat nines forever, implying that pi is a rational number, ha!

Over at X née Twitter, the anecdote is here, with a reply thread:

https://twitter.com/x/status/1742176058013622511

A natural question is “what about seven 9’s or eight 9’s , or …?"
Some wag replied that he used Mathematica to pin down positions
in pi of 7- and 8- nines. I (being “loquitur” on that forum, too) replied that
you don’t even need to program anything to find out about nine nines--
just use ‘grep’ on any old Mac.

To wit, grab a sufficiently large number of digits of pi (I chose a
billion, but 1GB is little these days) from somewhere such as:

22.4 Trillion Digits of My Pi World Record

and then run a Unix command from the terminal, like

“fold -w 1000 bigfileofpi | grep -b —colour -n 999999999”

to see the march-of-nine nines light up in red! My primitive
command is not sophisticated enough to specify exactly which
position in pi a given digit string occurs (due to the vagaries of
‘fold’ inserting newlines), but also because a given string may
overlap the end of a text line and the beginning of the next.

Such is my story of nine nines on pi day.

—loquitur

P.S. There’s also the related recreational math activity of searching
for a name in pi, perhaps by using a suitably large encoding of
pi in base 27, allowing for English letters and a space.

P.P.S. Here’s a pic of the now-defunct Pi Bar near my neighborhood
in San Francisco:

View attachment 1028031

Thank you for giving me a delightful digression from the technical challenges of my day!

 

[HVM]

...If there was a pilot, I'd have called the action of the grid fins "pilot induced oscillation"...

I think point where Grid fins lost their effectiveness there should have been thirteen Raptors firing and providing all TVC needed.

 

[JB47394]

Scott is an observant guy.

 

[ggr]

Scott is an observant guy.

Why is there soot/smoke coming out on takeoff? I thought Methane burned clean?

 

[JB47394]

Why is there soot/smoke coming out on takeoff? I thought Methane burned clean?

Methane is a carbon fuel, so if the engines are running fuel rich at all, there would be some crud being formed. One possible source of an enriched propellant could be methane film cooling. If SpaceX is at all aggressive with that cooling, they could end up with a bit of excess methane going into the exhaust and producing partially oxidized products such as methanol, formic acid, formaldehyde and higher hydrocarbons. Gunk.

 

[JB47394]

There will be a mishap investigation into the loss of both vehicles.

https://twitter.com/x/status/1768303183862927810

 

[JB47394]

Also, Manley posted something I saw briefly as well, but forgot to mention... looks like mostly tiles:

At 1:18:45 in the SpaceX video, what looks like little bits of ice start floating past the camera. Right at 1:18:53, the camera jumps, and then the dark debris floats by. I wonder if there was tile debris in the flap mechanism from earlier in the flight, and the motors eventually overpowered the debris, crushing both it and whatever it was jammed against.

It may be nothing, and the sudden camera movement was just a normal, sudden flap movement, but it looks like a whipsaw motion that would match up with a jammed, then freed, then stabilized motorized joint.

 

[ecarfan]

Scott is of the opinion that the Pez door test failed. He also noted that there appeared to be residual atmosphere inside the cargo bay that vented out when the door opened slightly.

 

[ecarfan]

There will be a mishap investigation into the loss of both vehicles.

I would think that would be mandatory given that SpaceX essentially lost control of both vehicles. Yes, they both probably impacted within their target areas, but they did not appear to be under control during final descent.