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SpaceX Starship missions 1

thebard3

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May 4, 2018
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Starting a dedicated thread here. After a pretty smooth flight test today, assuming no big anomalies occurred with the ground systems, it looks like SpaceX is back on track with testing and development. We should see more flights in the near future.
Both vehicles were lost before completing their full mission but a huge step forward today to see both executing the primary flight goals.

Brad Waybright

The more you know, the more you know you don't know.
 
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let's wait for a full survey of stage 0, but for now it looks like the "nay-sayers" have been "schooled".

good flight, could've been better.

Hot staging seemed to work well ... some details to be worked sure. I wonder if it'd be better to keep more engines alight and throttle them down more ?

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.
 
I saw some pictures that show damage to a couple of the vertical tanks that were also damaged by debris from the first launch. Not enough detail to suggest if it was from debris or just blast effects. I think they are not for cryogenic storage anymore, maybe just water. I don't think anyone should think that there would never be any damage of some kind to the launch pad, given the amounts of energy involved. NASA experienced significant damage to the SLS pad that was not expected as well.

Brad Waybright

The more you know, the more you know you don't know.
 
Let's wait for the investigation. I agree I expet some damage, but nothing like the previous launch. Now the water and plate solution seems to have worked really well.

Something I've asked on YT (Marcus House) ... Apollo and others ? had sparklers under the rocket, lit immediately prior to launch (to prevent fuel accumulating). but not so SpaceX ? Thoughts ?

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.
 
Those sparklers under the shuttle? IDK, other than that the fuel was hydrogen instead of methane. I believe hydrogen has an exlosive range greater than most volatile vapors, or so I heard.

Brad Waybright

The more you know, the more you know you don't know.
 
Wasn't sure about the Shuttle ... they wouldn't be under the SRBs !

Ok, the fuel could make sense ... Apollo was LH2/LOX, and I'll accept that H2 is more explosive than CH4 ... I still wouldn't want a cloud of Methane in the relatively closed environment under a rocket ...

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.
 
The first stage of the Saturn V burned RP-1, a more precisely refined form of kerosene. I don't think they used the 'sparklers' under that rocket.
Yes, I think running the sparklers under the SRB's might have had some kind of unintended consequence, like a RUD on the pad, maybe [sad]

Brad Waybright

The more you know, the more you know you don't know.
 
Launch track and disintegration debris pattern from the first stage... and the upper stage.. Flight #2. Hmmmm I wonder if the actual... farther-down-range... upper stage debris field(s) was also anticipated and built-into in the emergency planning.

Debris field model [predicted?]...
StarShip_F2_Debris_Re-Entry_Path2_eatqpo.jpg


Apparent upper-stage debris field...
StarShip_F2_Debris_Re-Entry_Path1_y00lb3.jpg


WX sat radar track of upper-stage debris...
StarShip_F2_Debris_Re-Entry_Path3_sjdwea.jpg


I had presumed that the launch track would be thru the gap between south Cuba and Cancun MX. Boy-o-boy was I off base. The F#2 launch track 'threads' the gap between the Florida Keys and the Northern coasts of Cuba, Haiti, Dom-Rep and Puerto Rico. The debris from the F2 upper-stage appears to have ended-up in the sea just north of Puerto Rico. Hope there were no close-up/in-person witnesses land/sea/air.

I suppose that on-board engineering video/images/real-time-data were being held-back by SpaceX for mishap analysis...?

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov
 
When SpaceX first discussed reusable hardware, I though it would be a real game changer. Being able to use a booster 4 or maybe 5 times would impart a huge savings per pound to orbit per launch.
I just watched a Falcon 9 booster complete it's 17th mission and the 250th recovery overall for SpaceX.

Brad Waybright

The more you know, the more you know you don't know.
 
tb3...

The Falcon 9 is a proven 'winner'... Routine LEO missions are happening with 'with monotonous regularity'.

I hope SpaceX can Scale-up and make it happen with Starship launch vehicles... Routine LEO and beyond... 'with monotonous regularity'.

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov
 
WKTaylor said:
I hope SpaceX can Scale-up and make it happen with Starship launch vehicles... Routine LEO and beyond... 'with monotonous regularity'.
I'm feeling it!

Brad Waybright

The more you know, the more you know you don't know.
 
FT3 is underway. Looks like Starship made it to nominal orbit. The booster was intended for a soft water landing, and it looks like that didn't go well. I don't know if it made the correct return trajectory, but all looked good until the last few seconds and I believe all of the engines needed didn't light. Waiting a half hour or so for Starship to begin it's return maneuvers.

Brad Waybright

The more you know, the more you know you don't know.
 
Starship appears to have broken up on reentry. Live video seemed to show A LOT of tiles departing when the entry phase started. It was pretty spectacular to watch. No way to know now what was the root cause.

Brad Waybright

The more you know, the more you know you don't know.
 
FT3 Lift-Off Video...
Looks like the first stage had 'failed-relight' of the required retro engines and hit the water at high velocity. First Stage attained orbit.

Bard... any further info/links for orbital 'coast/testing' and 're-entry' and 'soft-water landing attempt'????

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov
 
Not sure what was their agenda for in flight testing. Boost phase, hot separation, and orbit insertion was apparently nominal. They mentioned that opening and closing the 'Pez' door was successful. It looked like several attitude adjustments were made and also that the re-entry profile was nominal for the first while, so the de-orbit burn worked at least in part. The test agenda also included transfer of fuel and a re-light of one of the sea level engines (in vacuum). No word yet on the status of any of that. It seemed that a lot of thermal protection tiles fell off very early during re-entry. No idea if that was a primary cause, contributor, or maybe of no consequence for the loss of the vehicle.

Brad Waybright

The more you know, the more you know you don't know.
 
Loss of signal @25724-KPH, 65-KM altitude...
Looked like attitude control seemed to falter ~1-to-2 minutes before LOS

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov
 
The camera is mounted in one of the control surfaces, winglets, or whatever they are called. It's obvious when it moves and I never really saw anything that looked like anything other than a stop to stop movement. I'd expect small gradual movements to maintain attitude if it was on a stable path. I'm sure we'll get more on it in the coming days.

Brad Waybright

The more you know, the more you know you don't know.
 
I watched it live and re-watched it all this evening.
I'm pretty sure the Starship was slowly tumbling, both end-over-end, and in roll. The wings didn't seem to help. As it passed through a brief period of "belly first" orientation, you could see the wings being moved in an attempt to get it to stabilize in that orientation. If you review the SpaceX feed at 00:45:26, that's a moment when it's in a good orientation and the wings are straightened in an attempt to get some control surface lift. However they are still 109km up, and there basically isn't any air to use. 20 seconds later the craft has rolled onto its "back". Note the debris coming off (not sure what it is but probably the tiles themselves) and the direction it blows away. Soon afterward, the shock becomes visible, but still the craft is not orienting itself aerodynamically. At the 00:47:00 mark the craft's tumble carries it over and it's pointed backwards. The swell of red/yellow the fills the camera view is plasma from the shock at the motor end washing toward the nose and of course blanketing the camera.

This Starship didn't have reaction thrusters, which would have been useful to stop the roll and pitch motions while the wings are still ineffective, and maintain its attitude until they do. You'd think that an aerodynamic velocity high enough to ionize the oxygen & nitrogen atoms impinging on the surface would be enough to generate a sizeable force, but actually it doesn't have to be. One atom hitting the surface at Mach 10 will be ionized but impart no force to the spacecraft, and it doesn't take a lot of atoms to make a glowing plasma.

The X-15 had the same problem, and almost killed Neil Armstrong for the same reason. Having seen this on video now and seeing just how useless aerodynamic surfaces can be at hypersonic velocities with too much altitude, I want to go back to re-read the NASA papers about the X-15 missions. I might have a fresh understanding of what those pilots wrote about their experiences.
 
What Went Wrong With Starship's Third Test Flight? ~48-minutes

SpaceX Starship IFT3 Aftermath: New Insights Paint Different Picture! This fellow is very enthusiastic about SpaceX...

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov
 
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