SpaceX Starship : First Flight : Starbase, TX : 20 April 2023 - DISCUSSION

[Lars-J]

Is there any chanche to see SS flip, if it makes through reentry, via a non SpaceX camera?

There won’t be any non-SpaceX cameras out in the ocean 100kM northwest of Kauai. My guess is that a Starlink antenna will be installed on the SS and the flight will be live streamed.

The SN15 test flight appears to be the first time the vehicle had a Starlink antenna in place. The stream certainly did not work very well, but the problems should be correctable.

There will likely by assets in the air (from NASA or contracted) to image the re-entry, even if it is not streamed live. Dragon 1 re-entry footage was captured from the Hawaii area.

[oldAtlas_Eguy]

OK Orbit but one that is just barely such that it will rapidly decay to the point it will reenter around Kauji. If on the way up it is off target (this is just a few 10s of m/s) then it will either splash before or after Kuaji into the Pacific somewhere.

[AC in NC]

OK Orbit but one that is just barely such that it will rapidly decay to the point it will reenter around Kauji. If on the way up it is off target (this is just a few 10s of m/s) then it will either splash before or after Kuaji into the Pacific somewhere.

I can't reconcile "achieve orbit" with rapidly decaying around T+90mins.  That just doesn't compute for me.  Achieving Orbit necessarily means a full once-around.

"until performing a powered, targeted landing" suggests to me that they would achieve a meaningful orbit insertion and then perform a deorbit burn, or perhaps even a deorbit-acceleration burn to test EDL at a higher than orbital velocity.

[2megs]

...
But there's no trajectory that can complete a full orbit (i.e. 360 degrees east from Boca to go past Boca again), and then go another 294 + 22.5 degrees east to Kauai, and still fit that timeline.... right?

So I'm assuming this can't complete a full orbit. IMO that's for the best on the first flight, no risk of stranding a Starship in a low unstable orbit, re-entering at an unpredictable place.
...

Correct.  However, they do not necessarily need to complete a full orbit to get the data they need (at least at this point).

Certainly. It's worth pointing out that even if they don't complete an orbit, they can exceed orbital speed (a scalar quantity) for atmospheric re-entry purposes, but not achieve an orbital velocity (a vector with a direction as well as a magnitude) that would take them around the earth.

[nacnud]

You can be moving at orbital speeds yet still have the perigee within the atmosphere

edit: velocity != speed, doh

[Jcc]

Is there any chanche to see SS flip, if it makes through reentry, via a non SpaceX camera?

I bet NASA would like to track it from the air, like they did the first Starship 10Km flight

[joek]

Will this Starship have a heatshield on it?

It better if they're really planning on a "soft ocean landing".

Agree.  And if anyone remembers, the specific verbiage in the FAA launch license way-back for F9 (LLS 17-096) was (emphasis added):

... Flight includes landing of the Falcon 9 first stage either on a droneship in the ocean or in the ocean. ...

[OneSpeed]

OK Orbit but one that is just barely such that it will rapidly decay to the point it will reenter around Kauji. If on the way up it is off target (this is just a few 10s of m/s) then it will either splash before or after Kuaji into the Pacific somewhere.

I can't reconcile "achieve orbit" with rapidly decaying around T+90mins.  That just doesn't compute for me.  Achieving Orbit necessarily means a full once-around.

"until performing a powered, targeted landing" suggests to me that they would achieve a meaningful orbit insertion and then perform a deorbit burn, or perhaps even a deorbit-acceleration burn to test EDL at a higher than orbital velocity.

This is not a very hi-res image, but the orbit *looks* circular.

Edit: Changed my mind. Entry appears to be at around 70km altitude if it is 100km from Kauai. It could be ballistic.

[daavery]

Who has make this plan? What is the FCC?

The FCC is the Federal Communications Commission, and SpaceX has to get permission to use their telemetry channels every time a prototype rocket is launched.  Eventually they get license to use the channels when the rocket moves from the experimental stage and becomes fully functional rocket.

actually for now commercial space needs an STC for every flight becuase commercial rocket comms are not a class of operation that is in the regs yet

[Orbiter]

This is going to be such a wild launch. Do we know how many Raptors BN3 will have? We're talking about a liftoff thrust that at minimum will rival the Saturn V.

[Lars-J]

This is going to be such a wild launch. Do we know how many Raptors BN3 will have? We're talking about a liftoff thrust that at minimum will rival the Saturn V.

Oh it should exceed it by some margin, unless they launch both Starship and SuperHeavy partially filled (allowing them to use  fewer raptors).

This could be the first flight test of Raptor-Vacuum. Unless they do a high sub-orbital attempt with SN2X - which is possible since Vacuum Raptor can be fired at sea level. But this aggressive time schedule suggests they may opt to go directly orbital. But they could also do both...

[beentheredengthat]

What a huge leap!

Booster first flight, MAX Q, MECO, separation, (vac raps?), Full suite of heat tiles, Reentry heating

I'm going to need a party thread to discuss this one.

[DistantTemple]

Is there any chanche to see SS flip, if it makes through reentry, via a non SpaceX camera?

There won’t be any non-SpaceX cameras out in the ocean 100kM northwest of Kauai. My guess is that a Starlink antenna will be installed on the SS and the flight will be live streamed.

The SN15 test flight appears to be the first time the vehicle had a Starlink antenna in place. The stream certainly did not work very well, but the problems should be correctable.

There will likely by assets in the air (from NASA or contracted) to image the re-entry, even if it is not streamed live. Dragon 1 re-entry footage was captured from the Hawaii area.

The choice of "100kM northwest of Kauai" is likely deliberate to make such observation flights easier! If SX has a flexible launch window, crews and planes can be on standby, and have a comfortable 90 mins to (finish their tea,) get airborne, travel 100km or so and climb to observation station..... adjusting for trajectory etc.... And SX personnel can also be on hand.

Also apart from Cuba South Africa (Namibia and Botswana) and Papa New Guinea (interesting?), there is no land at all on the great circle, until you overshoot and hit Mexico. So there is the lowest possible chance of dropping on anyone if below the expected trajectory.

[Framryk]

Reading Eric Berger's excellent book (https://forum.nasaspaceflight.com/index.php?topic=52010.0), I note the early history of SpaceX used Kwajalein Atoll (and specifically, Omelek Island) during the Falcon 1 days. Does this and the associated ballistic missile tracking capability on the islands aid in following the first Starship orbit? Is this on the track from a Boca Chica launch to NW Kauai splashdown? (I'd love to simulate the flight path but don't have the skill or software!)

[raivo45]

I guess that landing SH on a barge/droneship/oilrig means that it will likely have legs. 

[wannamoonbase]

What a huge leap!

Booster first flight, MAX Q, MECO, separation, (vac raps?), Full suite of heat tiles, Reentry heating

I'm going to need a party thread to discuss this one.

Yeah the full heat shield, that's going to be the interesting pucker item on teh flight.

Maybe it's wrong to assume that I expect the booster to execute it's full flight and test objectives on the first flight out.  Why not, it's only more capable than a Saturn V!

[rpapo]

Very cool. What I find interesting is that the staging is later than anticipated, MECO seems to be about 20-30 seconds later than F9. Although it is possible that once the booster does a full boost-backs to the launch pad they will end up staging earlier.

Idea: SH is stainless steel.  F9 is Al.  SH should be able to tolerate reentry heating better than F9.  Unless the engine compartment cannot handle it.

[DistantTemple]

Reading Eric Berger's excellent book (https://forum.nasaspaceflight.com/index.php?topic=52010.0), I note the early history of SpaceX used Kwajalein Atoll (and specifically, Omelek Island) during the Falcon 1 days. Does this and the associated ballistic missile tracking capability on the islands aid in following the first Starship orbit? Is this on the track from a Boca Chica launch to NW Kauai splashdown? (I'd love to simulate the flight path but don't have the skill or software!)

Yes that makes logical sense. Kwajalein Atoll seems to be about 100km from the track of the apparent SS "orbit". Perfect

[chopsticks]

"until performing a powered, targeted landing" suggests to me that they would achieve a meaningful orbit insertion and then perform a deorbit burn, or perhaps even a deorbit-acceleration burn to test EDL at a higher than orbital velocity.

While this would be cool and a proper definition of being in orbit, I'm quite doubtful that perigee will extend beyond the atmosphere for this flight. Starship would have to reorient itself retrograde and perform a deorbit burn (not a small thing to ask on its maiden flight in space) then reorient itself again prograde for re-entry. This would have to be done in a timely manner with not much room for error. I don't know, it just seems like a large risk item for the first flight, and given the global reaction of the Long March 5B re-entry, I have a hard time believing that a low orbit like this would have to be reliant on a deorbit burn for the first flight.

[DecoLV]

given the global reaction of the Long March 5B re-entry, I have a hard time believing that a low orbit like this would have to be reliant on a deorbit burn for the first flight.

Not only that, but as you inferred, the plan basically rules out entry concerns by overflight countries...including the US! The agency with the most concerns is the FAA not the FCC.  And if there is no overflight and no land landing at all by either booster or Starship,those safety and environmental concerns become pretty moot for this flight, don't they!?