The renamed Mr. Steven gigantic net fairing catcher ship for the first time ever caught a fairing in the air, operating under her new name of GO Ms. Tree. I confess I'm surprised--it appeared to me that they were not particularly close to grinding down the error budget enough to get this even occasionally, let alone routinely. I'm still a bit sceptical, but imagine they will keep trying unless they get really, really happy with the refurb after a swim option. We'll know they are getting serious if they outfit a second catcher ship or demonstrate a way to catch both fairing halves with the one ship.
Over on NASASpaceFlight.com, people have chewed over the failing center core barge landing video a lot. Until/unless Elon tweets, we don't know much of why, but many people think it looks like things were nearly or completely normal until very near the end. Many suspect that a sudden throttle up and extreme gimbal at that point was not itself the failure, but instead a software-commanded "save the droneship" abort after a condition was detected inconsistent with successful landing.
While I can't give any personal assessment it clearly got very close--the landing legs deployed and the exhaust lit up the deck of the barge. So maybe the "got toasted too much by a hot re-entry to work properly" notion is wrong. Or maybe it is correct and almost everything worked properly but the toasting ruined something.
So far three times out of three the side boosters on a Heavy have landed, and the center has been lost. I wonder if someone is suggesting they just plan on expending the center? That would raise mission performance and save on recovery fleet operational costs. But I doubt it. Re-use wherever possible is close to a religion at SpaceX.
I slept through the whole thing. I guessed that the amount of delay meant eventually they'd go to a postponement.
Somebody snipped forty seconds out of the SpaceX webcast for the STP-2 mission that show the "caught" fairing still up in the net carried by recovery ship GO Ms. Tree. If you were still watching the webcast at T+1:14:00 this will not be new to you.
OK. That's a pretty convincing reason. Seems that implies that thrust vectoring is the main player near landing, fins being useless at low speed, and probably vice-versa high up. The wee body mounted nitrogen thrusters insufficiently helpful here. Aside : having a bigger drone ship doesn't solve this aspect.
It's nice to know that it nearly did it and was waved off, but unlike a bad aircraft carrier approach you can't go around again. But that's the deal with this hover-slam business, it is like one-shot-only at a carrier deck ( in order of preference ): land it on deck, land it in water or splat it on deck. SpaceX has good experience with all three.
So here's the business/technical intersection. You always have to deliver the goods to orbit on spec. Always. Good recoveries is a profit bonus via re-use. Landing is only useful if it leads to not having to make another core. But a long throw implies high re-entry speed. How much does one spend to research/enact a centre core toughening to stop this again ?
{ Lengthening the barrel to stuff more fuel in has exponential written all over it }
I wonder if SpaceX has broken even yet? Or are they still loss-leading their way into the market ? I can't see anyone following SpaceX's path yet, what with all the hard won knowledge/nuances of their technical wizardry.
Cheers, Mike.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
But a long throw implies high re-entry speed. How much does one spend to research/enact a centre core toughening to stop this again ?
One possibility is just not offering quite this much launch performance again not sold as center core expended. You want this much (or somewhat more) performance, we charge you for an expended center core, and bank the savings on not sending out the recovery fleet. You can get by with just a little less launch performance and we use the resulting center core fuel residual increase to get the re-entry speed down enough lower that we expect not to see this failure.
Unlike Geo-synchronous comsat and big recon sat launches, there was nothing that set the performance requirement for this launch in stone. Just leave a few of the extra credit birds behind, or have a little less energetic boost to a heavy important one, and you'd be "in the zone" for known ASDS recovery success.
On the other hand, if you have a good idea what burned through and it is a cheap fix, go ahead and do it (unless NASA, Air Force, or other customer impediments mean you'd now need a bunch of additional launches to "certify" the changes.)
Quote:
I can't see anyone following SpaceX's path yet, what with all the hard won knowledge/nuances of their technical wizardry.
Certainly the low SpaceX prices and the substantial amount of demonstrated launch success have concentrated minds at several organizations. Even the previous low-price champs in China are talking about plans to get their costs down, including some recovery/reuse thoughts. Ariane has pushed hard toward lower cost for their next generation, and clearly thinks it does not go far enough. Their re-use idea so far leans toward recovering the engines, not the entire stage. ULA has made similar noises. Then there is the whole host of guys trying to compete in the smaller payload corner of the market. Ride-share may be cheap for cubesats, but you lose control of your life in a big way and may wait for years. So an itty-bitty rocket launching from New Zealand when you want it to, or something that starts up under a White Knight or Cosmic Girl and then looks like a latter-day Pegasus is in a way part of the cost to reach a particular goal competition, even if the price per kilogram to LEO is not competitive.
But a long throw implies high re-entry speed. How much does one spend to research/enact a centre core toughening to stop this again ?
One possibility is just not offering quite this much launch performance again not sold as center core expended. You want this much (or somewhat more) performance, we charge you for an expended center core, and bank the savings on not sending out the recovery fleet. You can get by with just a little less launch performance and we use the resulting center core fuel residual increase to get the re-entry speed down enough lower that we expect not to see this failure.
Unlike Geo-synchronous comsat and big recon sat launches, there was nothing that set the performance requirement for this launch in stone. Just leave a few of the extra credit birds behind, or have a little less energetic boost to a heavy important one, and you'd be "in the zone" for known ASDS recovery success.
On the other hand, if you have a good idea what burned through and it is a cheap fix, go ahead and do it (unless NASA, Air Force, or other customer impediments mean you'd now need a bunch of additional launches to "certify" the changes.)
The hard part is the fix likely involves adding shielding and added material is added weight. You could end up fixing it and now be in no better place than not fixing it and just putting a performance limit on the tube.
Does anyone know if they pulled the center core out of the drink to get a good look at it and see if the fix might be simple of more complex?
The "water tower spaceship" matter at Boca Chica Texas (aka the SpaceX StarHopper) has idled for a little while pending arrival of a working Raptor rocket engine. Serial Number 6, which has survived multiple test runs at McGregor in recent days arrived overnight, and was unceremoniously moved under and lifted up into the "Hopper" test vehicle.
This version of a video taken by a local resident was edited to stabilize the image and lower the pixel count, but was NOT speeded up!
With the arrival of an engine believed to work more than well enough to support the first un-tethered firing, perhaps we'll finally see the Hopper hop, though I'd not be surprised if they tether the vehicle the first time or two they light the fire.
A piece of published permitting documentation limits hop height to 25 meters, so without some additional permission slip, the first free flights will be really tiny.
The launch of India's second lunar mission has been halted, less than an hour before the scheduled blast-off, to due to a technical problem, says the Indian Space Research Organisation.
If successful, India will become the fourth country to make a soft landing on the Moon's surface.
Only the US, China and the former Soviet Union have been able to do so.
The $150m mission - Chandrayaan-2 - aims to gather data on water, minerals and rock formations on the Moon.
The Indian-made satellite had been scheduled for launch at 02:51 local time on Monday (21:21 GMT Sunday) from Sriharikota space station on India's eastern coast.
But the countdown was halted 56 minutes before the launch time after a "technical snag was observed in launch vehicle system," Isro said. A new launch time will be announced later.
India is looking to take a giant technological leap with a second unmanned mission to the moon, aimed at landing a rover near the unexplored south pole.
The blast-off of Chandrayaan-2 from Satish Dhawan Space Centre in Sriharikota in the southern Indian state of Andhra Pradesh is scheduledat 2.51am local time on Monday (2121 GMT, Sunday).
A successful launch will be the first among several nail-biting steps planned ahead, which, if successful, will put India in a select group of spacefaring nations.
Chandrayaan-2 is a multistage moon mission through which the Indian Space Research Organisation (ISRO) plans to place a spacecraft in the lunar orbit 22 days after the launch.
Nearly a month after that, on September 6 or 7, a landing craft carrying a rover should separate from the orbiter and attempt a controlled descent to land on the surface at the south pole.
ISRO is attempting what is called a "soft landing", a feat achieved only by the former Soviet Union, the United States and China so far.
No landing video from today's SpaceX launch for the first stage which was expended. Perhaps this was penance for the fact that a static fire explosion destroyed the previous payload for this customer. Expending the first stage let them give a more emphatic boost to the cargo, which in turn lets it get to paying orbit sooner while using less onboard fuel--so potentially a longer useful life at both ends.
But Ms. Tree again succeeded in catching a fairing half. This time there seems to have been a videography drone flying formation with the catching net ship.
I wondered on the first successful catch whether that was just luck of the once-in-a-while, but two in a row suggests they have figured out something that has materially reduced the error dispersion from before.
It is very cute. On the other hand, Elon himself recently expressed doubt as to whether this particular effort had been worthwhile on balance. I think we'll get a clue if they provision a second catching ship so that they can catch both halves.
? centre ran out of fuel
)
? centre ran out of fuel to manoeuvre ?
Cheers, Mike.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
The renamed Mr. Steven
)
The renamed Mr. Steven gigantic net fairing catcher ship for the first time ever caught a fairing in the air, operating under her new name of GO Ms. Tree. I confess I'm surprised--it appeared to me that they were not particularly close to grinding down the error budget enough to get this even occasionally, let alone routinely. I'm still a bit sceptical, but imagine they will keep trying unless they get really, really happy with the refurb after a swim option. We'll know they are getting serious if they outfit a second catcher ship or demonstrate a way to catch both fairing halves with the one ship.
Over on NASASpaceFlight.com, people have chewed over the failing center core barge landing video a lot. Until/unless Elon tweets, we don't know much of why, but many people think it looks like things were nearly or completely normal until very near the end. Many suspect that a sudden throttle up and extreme gimbal at that point was not itself the failure, but instead a software-commanded "save the droneship" abort after a condition was detected inconsistent with successful landing.
While I can't give any personal assessment it clearly got very close--the landing legs deployed and the exhaust lit up the deck of the barge. So maybe the "got toasted too much by a hot re-entry to work properly" notion is wrong. Or maybe it is correct and almost everything worked properly but the toasting ruined something.
So far three times out of three the side boosters on a Heavy have landed, and the center has been lost. I wonder if someone is suggesting they just plan on expending the center? That would raise mission performance and save on recovery fleet operational costs. But I doubt it. Re-use wherever possible is close to a religion at SpaceX.
I slept through the whole thing. I guessed that the amount of delay meant eventually they'd go to a postponement.
Somebody snipped forty
)
Somebody snipped forty seconds out of the SpaceX webcast for the STP-2 mission that show the "caught" fairing still up in the net carried by recovery ship GO Ms. Tree. If you were still watching the webcast at T+1:14:00 this will not be new to you.
https://youtu.be/H-EVcg_48sk
Not much to see except the remarkable fact it is there--do mind that the fairing is the thing up in the air off to the left.
Regarding the center core
)
Regarding the center core landing failure, someone asked Elon:
"Elon do you know what went wrong?"
and got the direct answer:
"High entry force & heat breached engine bay & center engine TVC failed"
Then a frequently-answered questioner asked in direct sequence:
"And did the computer know that and know to divert?!?!"
to which Elon further replied:
"Most likely. It is programmed to do so."
Hummmmmm.....
OK. That's a pretty
)
OK. That's a pretty convincing reason. Seems that implies that thrust vectoring is the main player near landing, fins being useless at low speed, and probably vice-versa high up. The wee body mounted nitrogen thrusters insufficiently helpful here. Aside : having a bigger drone ship doesn't solve this aspect.
It's nice to know that it nearly did it and was waved off, but unlike a bad aircraft carrier approach you can't go around again. But that's the deal with this hover-slam business, it is like one-shot-only at a carrier deck ( in order of preference ): land it on deck, land it in water or splat it on deck. SpaceX has good experience with all three.
So here's the business/technical intersection. You always have to deliver the goods to orbit on spec. Always. Good recoveries is a profit bonus via re-use. Landing is only useful if it leads to not having to make another core. But a long throw implies high re-entry speed. How much does one spend to research/enact a centre core toughening to stop this again ?
{ Lengthening the barrel to stuff more fuel in has exponential written all over it }
I wonder if SpaceX has broken even yet? Or are they still loss-leading their way into the market ? I can't see anyone following SpaceX's path yet, what with all the hard won knowledge/nuances of their technical wizardry.
Cheers, Mike.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
Mike Hewson wrote:But a long
)
One possibility is just not offering quite this much launch performance again not sold as center core expended. You want this much (or somewhat more) performance, we charge you for an expended center core, and bank the savings on not sending out the recovery fleet. You can get by with just a little less launch performance and we use the resulting center core fuel residual increase to get the re-entry speed down enough lower that we expect not to see this failure.
Unlike Geo-synchronous comsat and big recon sat launches, there was nothing that set the performance requirement for this launch in stone. Just leave a few of the extra credit birds behind, or have a little less energetic boost to a heavy important one, and you'd be "in the zone" for known ASDS recovery success.
On the other hand, if you have a good idea what burned through and it is a cheap fix, go ahead and do it (unless NASA, Air Force, or other customer impediments mean you'd now need a bunch of additional launches to "certify" the changes.)
Certainly the low SpaceX prices and the substantial amount of demonstrated launch success have concentrated minds at several organizations. Even the previous low-price champs in China are talking about plans to get their costs down, including some recovery/reuse thoughts. Ariane has pushed hard toward lower cost for their next generation, and clearly thinks it does not go far enough. Their re-use idea so far leans toward recovering the engines, not the entire stage. ULA has made similar noises. Then there is the whole host of guys trying to compete in the smaller payload corner of the market. Ride-share may be cheap for cubesats, but you lose control of your life in a big way and may wait for years. So an itty-bitty rocket launching from New Zealand when you want it to, or something that starts up under a White Knight or Cosmic Girl and then looks like a latter-day Pegasus is in a way part of the cost to reach a particular goal competition, even if the price per kilogram to LEO is not competitive.
archae86 wrote:Mike Hewson
)
The hard part is the fix likely involves adding shielding and added material is added weight. You could end up fixing it and now be in no better place than not fixing it and just putting a performance limit on the tube.
Does anyone know if they pulled the center core out of the drink to get a good look at it and see if the fix might be simple of more complex?
The "water tower spaceship"
)
The "water tower spaceship" matter at Boca Chica Texas (aka the SpaceX StarHopper) has idled for a little while pending arrival of a working Raptor rocket engine. Serial Number 6, which has survived multiple test runs at McGregor in recent days arrived overnight, and was unceremoniously moved under and lifted up into the "Hopper" test vehicle.
This version of a video taken by a local resident was edited to stabilize the image and lower the pixel count, but was NOT speeded up!
https://www.youtube.com/watch?v=tcJCnJP9cjQ
With the arrival of an engine believed to work more than well enough to support the first un-tethered firing, perhaps we'll finally see the Hopper hop, though I'd not be surprised if they tether the vehicle the first time or two they light the fire.
A piece of published permitting documentation limits hop height to 25 meters, so without some additional permission slip, the first free flights will be really tiny.
https://www.aljazeera.com/new
)
edit delay https://www.bbc.com/news/world-asia-india-48905147
https://www.aljazeera.com/news/2019/07/india-prepares-land-rover-moon-unmanned-mission-190714120432937.html
No landing video from today's
)
No landing video from today's SpaceX launch for the first stage which was expended. Perhaps this was penance for the fact that a static fire explosion destroyed the previous payload for this customer. Expending the first stage let them give a more emphatic boost to the cargo, which in turn lets it get to paying orbit sooner while using less onboard fuel--so potentially a longer useful life at both ends.
But Ms. Tree again succeeded in catching a fairing half. This time there seems to have been a videography drone flying formation with the catching net ship.
https://www.youtube.com/watch?v=kesCAxPSWcY
I wondered on the first successful catch whether that was just luck of the once-in-a-while, but two in a row suggests they have figured out something that has materially reduced the error dispersion from before.
It is very cute. On the other hand, Elon himself recently expressed doubt as to whether this particular effort had been worthwhile on balance. I think we'll get a clue if they provision a second catching ship so that they can catch both halves.