Listed as an expended first stage. Still one of the small vessels is out--not the tug which tows the barge. So it seems likely they are continuing their work toward fairing recovery.
Regarding fairing recovery: there has been a recent clarification that suggests the several times mentioned "bouncy castle" is not a seaborne impact attenuation device, but instead a fairing born flotation provision meant to keep the fairing afloat pending pickup. There are also steerable parachutes, probably both to reduce final surface impact and also to get the fairing closer to a recovery asset. I've not heard what they have done to lessen reentry heating damage. The main booster needs a significant delta-V to reduce the atmospheric entry speed to something it can survive. It would seem a bit surprising if the fairing can just "take it".
I'm going to guess that the fairing has enough surface area compared to mass that it slows much easier in the upper reaches. It is also jettisoned before MECO and thus has less stored energy from velocity and altitude.
IIRC there was supposed to be a launch of paper airplanes from the ISS.
Not on the timelines I've observed or can find. Just looking around a little I see timelines with fairing jettison from 20 seconds to a minute after second stage ignition. Now mind you, the second stage acceleration is rather modest in the early going, so it is not lots faster and higher than the first stage, but it is definitely faster.
Do we know to what degree ( none ? ) they are able to control the attitude of the fairing after discard ?
Multiple reddit participants assert there have been "thrusters" on the fairing half for which recovery experimentation was tried. A minimalist approach would be to use the thrusters to attain a desired orientation as the air density built to the point of letting aerodynamics take over, then rely on fairing shaping in the Burt Rutan or Soyuz "carefree" style, or perhaps trim tabs (or maybe even fairing warping--Wright brothers style). A maximalist approach would require much bigger thrusters and much more fuel to actually control the orientation until down to parachute (or at least drogue deployment) speed. If anyone knows what they are really doing, I've not spotted it. One may suppose weight economy is a strong consideration. On the other hand, just as they forgo first stage recovery on the maximum performance missions, perhaps they may plan to save most of the fairing recovery hardware weight by not doing fairing recovery on the highest performance missions.
I believe this image is of a fairing half which bears some test recovery hardware.
As to one half vs. both, it may not be happenstance that the recovery ship brought back only one fairing half a few missions ago. Some participants believe that during the experiments so far they have only equipped one fairing half with recovery hardware.
After I typed all that, I found a place where a reddit participant stated this to be an Elon Musk quotation "So we actually have a parachute that - the fairing has it's own thruster control system and a steerable parachute. So it's its own little space craft. So the thrusters maintain its orientation as it comes in, as it reenters, and then we throw out the parachute and the parachute steers it to a particular location... so maybe what we'll have is kinda like a bouncy castle for it to land on..."
So that is where the "landing on a bouncy castle" story started. We'll see what turns up in the end. I doubt they are going to get enough accuracy out of a steerable parachute to land it on anything. So I still think water wings are more likely than bouncy castles.
Thank you for that detail. I'd heard much stuff also ( unclear ). It makes sense to test fairing only 1/2 at a time ie. case/control comparison. See what difference ( any ? ) it would make in trying to guide it.
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
Long March 5 failed in the second launch attempt. This is the new Chinese heavy lift launcher. I'm not posting a link as the stories I have seen are fragmentary. Some sources agree that trajectory anomaly was apparent within minutes, with staging much later than planned. I don't think the Chinese have shared much more than something like "not successful".
robl wrote:another launch
)
Listed as an expended first stage. Still one of the small vessels is out--not the tug which tows the barge. So it seems likely they are continuing their work toward fairing recovery.
Regarding fairing recovery: there has been a recent clarification that suggests the several times mentioned "bouncy castle" is not a seaborne impact attenuation device, but instead a fairing born flotation provision meant to keep the fairing afloat pending pickup. There are also steerable parachutes, probably both to reduce final surface impact and also to get the fairing closer to a recovery asset. I've not heard what they have done to lessen reentry heating damage. The main booster needs a significant delta-V to reduce the atmospheric entry speed to something it can survive. It would seem a bit surprising if the fairing can just "take it".
I'm going to guess that the
)
I'm going to guess that the fairing has enough surface area compared to mass that it slows much easier in the upper reaches. It is also jettisoned before MECO and thus has less stored energy from velocity and altitude.
IIRC there was supposed to be a launch of paper airplanes from the ISS.
Gary Charpentier wrote: It is
)
Not on the timelines I've observed or can find. Just looking around a little I see timelines with fairing jettison from 20 seconds to a minute after second stage ignition. Now mind you, the second stage acceleration is rather modest in the early going, so it is not lots faster and higher than the first stage, but it is definitely faster.
References:
Falcon 9 user guide (see page 28)
NROL-76 launch timeline
SES 10 launch timeline
Do we know to what degree
)
Do we know to what degree ( none ? ) they are able to control the attitude of the fairing after discard ?
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:Do we know
)
Multiple reddit participants assert there have been "thrusters" on the fairing half for which recovery experimentation was tried. A minimalist approach would be to use the thrusters to attain a desired orientation as the air density built to the point of letting aerodynamics take over, then rely on fairing shaping in the Burt Rutan or Soyuz "carefree" style, or perhaps trim tabs (or maybe even fairing warping--Wright brothers style). A maximalist approach would require much bigger thrusters and much more fuel to actually control the orientation until down to parachute (or at least drogue deployment) speed. If anyone knows what they are really doing, I've not spotted it. One may suppose weight economy is a strong consideration. On the other hand, just as they forgo first stage recovery on the maximum performance missions, perhaps they may plan to save most of the fairing recovery hardware weight by not doing fairing recovery on the highest performance missions.
I believe this image is of a fairing half which bears some test recovery hardware.
As to one half vs. both, it may not be happenstance that the recovery ship brought back only one fairing half a few missions ago. Some participants believe that during the experiments so far they have only equipped one fairing half with recovery hardware.
After I typed all that, I found a place where a reddit participant stated this to be an Elon Musk quotation "So we actually have a parachute that - the fairing has it's own thruster control system and a steerable parachute. So it's its own little space craft. So the thrusters maintain its orientation as it comes in, as it reenters, and then we throw out the parachute and the parachute steers it to a particular location... so maybe what we'll have is kinda like a bouncy castle for it to land on..."
So that is where the "landing on a bouncy castle" story started. We'll see what turns up in the end. I doubt they are going to get enough accuracy out of a steerable parachute to land it on anything. So I still think water wings are more likely than bouncy castles.
Thank you for that detail.
)
Thank you for that detail. I'd heard much stuff also ( unclear ). It makes sense to test fairing only 1/2 at a time ie. case/control comparison. See what difference ( any ? ) it would make in trying to guide it.
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
Long March 5 failed in the
)
Long March 5 failed in the second launch attempt. This is the new Chinese heavy lift launcher. I'm not posting a link as the stories I have seen are fragmentary. Some sources agree that trajectory anomaly was apparent within minutes, with staging much later than planned. I don't think the Chinese have shared much more than something like "not successful".
Just less than two hours
)
Just less than two hours http://www.spacex.com/webcast they go again from the cape. No landing, just use every drop for up.
Launch abort at minus nine
)
Launch abort at minus nine seconds .... no more for today. Awaiting on the reason, the onboard computer called it - something out of range.
"Guidance abort"
( edit ) So if it is a goer then "Next launch opportunity is on Monday, July 3 at 7:37 p.m. EDT, 23:37 UTC."
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
Another abort at T-10. This
)
Another abort at T-10. This candle just doesn't want to get lit. Maybe they can give up some fireworks on the 4th?