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#100
by
rsdavis9
on 30 Aug, 2016 19:08
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Also, don't forget the forthcoming "final" (final) [final?] thrust increase to the Fuller-Thrust version of the F9, that will likely help minimize the margin for recovery as well.
So we have the upcoming "final" thrust improvement which increases payload to orbit because of the reduction of gravity losses.
Has anybody calculated the 10 second no acceleration between meco and second stage startup. That would also seem to be a gravity loss and probably why the russians do the difficult start second stage before first stage shutdown.
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#101
by
shooter6947
on 30 Aug, 2016 19:14
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So we have the upcoming "final" thrust improvement which increases payload to orbit because of the reduction of gravity losses.
Has anybody calculated the 10 second no acceleration between meco and second stage startup. That would also seem to be a gravity loss and probably why the russians do the difficult start second stage before first stage shutdown.
Well, I mean, with no assumptions it would be 10m/s^2 * 10s = 100 m/s. Right?
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#102
by
rsdavis9
on 30 Aug, 2016 19:19
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Sounds too easy but also right.
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#103
by
John Alan
on 30 Aug, 2016 19:26
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If your not burning any fuel... how is that a gravity loss ?...
I call that...
"coasting in an upward direction... trading velocity for altitude... while clearances improve between a 210klbs thrust rocket engine... and some rather important hardware you plan to recover..."
Just my 2 cents...
On edit...
https://en.wikipedia.org/wiki/Gravity_dragTo quote from the above... my bolds added...
is a measure of the loss in the net performance of a rocket while it is thrusting in a gravitational field.
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#104
by
shooter6947
on 30 Aug, 2016 19:29
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Sounds too easy but also right.
True it is a *little* more complicated than that -- transverse orbital velocity reduces the gravity losses somewhat. But still going to be of that magnitude since the first stage isn't moving all THAT fast at MECO. So: a little less than 100m/s.
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#105
by
alang
on 30 Aug, 2016 20:03
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They may not try to recover at all as
a) the price for going first on a recovered stage and
b) reducing processing costs by not having to reapply thermal protection.
Also SpaceX may have decided they've learned all they need to prior to the next iteration which may not only be an engine upgrade but a TPS upgrade as well.
Edit: TPS not GPS.
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#106
by
mme
on 30 Aug, 2016 20:43
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They may not try to recover at all as
a) the price for going first on a recovered stage and
b) reducing processing costs by not having to reapply thermal protection.
Also SpaceX may have decided they've learned all they need to prior to the next iteration which may not only be an engine upgrade but a TPS upgrade as well.
Edit: TPS not GPS.
I'd be surprised if they did not attempt a landing. If nothing else it's more data for tuning landing and reentry burns. But add in being able to inspect a twice flown airframe and see if it can go again? Too much much valuable information to just throw away without even trying.
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#107
by
AncientU
on 30 Aug, 2016 20:53
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They may not try to recover at all as
a) the price for going first on a recovered stage and
b) reducing processing costs by not having to reapply thermal protection.
Also SpaceX may have decided they've learned all they need to prior to the next iteration which may not only be an engine upgrade but a TPS upgrade as well.
Edit: TPS not GPS.
They are not going for reuse (singular) -- they are going for many reuses, something like 10 between refurbishments and 100 overall. I suspect the unintended loss rate will remain the limiting factor of how many reflights they achieve for a significant time.
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#108
by
wannamoonbase
on 30 Aug, 2016 21:02
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They may not try to recover at all as
a) the price for going first on a recovered stage and
b) reducing processing costs by not having to reapply thermal protection.
Also SpaceX may have decided they've learned all they need to prior to the next iteration which may not only be an engine upgrade but a TPS upgrade as well.
Edit: TPS not GPS.
They are not going for reuse (singular) -- they are going for many reuses, something like 10 between refurbishments and 100 overall. I suspect the unintended loss rate will remain the limiting factor of how many reflights they achieve for a significant time.
I disagree. The size of the global market for space launch is limiting. Even at 5 flights per frame they would likely be able to serve 100% of the available market (excluding government funded launches for Russia, China, Europe and India) with 5-6 cores per year.
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#109
by
Wolfram66
on 30 Aug, 2016 21:23
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Q) will the price charged for the re-flown booster go down with each re-use? $40M for 1st reuse, $30M second reuse .... Min $25M? I know Ms Shotwell said ~$40M for reflown booster, but they've never reflown one. Will cost and time spent readying boosters for reuse go down with time.
Need to call in NASCAR, F1, IndyCar, or NHRA teams for processing strategies and brainstorming sessions.
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#110
by
whitelancer64
on 30 Aug, 2016 21:31
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Q) will the price charged for the re-flown booster go down with each re-use? $40M for 1st reuse, $30M second reuse .... Min $25M? I know Ms Shotwell said ~$40M for reflown booster, but they've never reflown one. Will cost and time spent readying boosters for reuse go down with time.
Need to call in NASCAR, F1, IndyCar, or NHRA teams for processing strategies and brainstorming sessions.
Probably not.
The overhead costs of launch - using the range, paying everyone who works there, payload integration, fuel, etc. - all stay the same. Also they are still building a new second stage every time, so there's the same overhead costs for that every time. Plus the additional costs for the first stage recovery, of shipping and testing all components, refurbishment if necessary, etc. will need to be there.
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#111
by
Dante2121
on 30 Aug, 2016 23:02
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Any word on what SpaceX is actually charging SES for this flight?
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#112
by
francesco nicoli
on 30 Aug, 2016 23:19
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They may not try to recover at all as
a) the price for going first on a recovered stage and
b) reducing processing costs by not having to reapply thermal protection.
Also SpaceX may have decided they've learned all they need to prior to the next iteration which may not only be an engine upgrade but a TPS upgrade as well.
Edit: TPS not GPS.
They are not going for reuse (singular) -- they are going for many reuses, something like 10 between refurbishments and 100 overall. I suspect the unintended loss rate will remain the limiting factor of how many reflights they achieve for a significant time.
I disagree. The size of the global market for space launch is limiting. Even at 5 flights per frame they would likely be able to serve 100% of the available market (excluding government funded launches for Russia, China, Europe and India) with 5-6 cores per year.
maybe later: I agree with you that the economics of having so many reuses doesn't look favourable for now (altough if they succeed they could switch personnel & infrastructure to other goals, such as the satellite constellation & mars).
However, I am pretty sure that they will attempt to recover this one.
On the one hand, the PR payback of being the first stage used-recovered-reused-recovered is immense.
On the other hand, data is essential too: it will be the first first stage ever flown twice, nobody knows for sure how will it fare, and you won't know unless you recover it.
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#113
by
AncientU
on 30 Aug, 2016 23:52
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They may not try to recover at all as
a) the price for going first on a recovered stage and
b) reducing processing costs by not having to reapply thermal protection.
Also SpaceX may have decided they've learned all they need to prior to the next iteration which may not only be an engine upgrade but a TPS upgrade as well.
Edit: TPS not GPS.
They are not going for reuse (singular) -- they are going for many reuses, something like 10 between refurbishments and 100 overall. I suspect the unintended loss rate will remain the limiting factor of how many reflights they achieve for a significant time.
I disagree. The size of the global market for space launch is limiting. Even at 5 flights per frame they would likely be able to serve 100% of the available market (excluding government funded launches for Russia, China, Europe and India) with 5-6 cores per year.
At the current projected-by-Spacex recovery rate of 70% on ASDS, they might not even be able to fly their own 2017 manifest to GTO with 6 cores. After the first flight, they'd be down to 4... after the third, down to 2 with only 13 flights accomplished. Those two have a 50-50 chance of surviving the next two flights. Six cores might just get them through the year... for their own scheduled flights.
Five flights per frame (on average) is not possible until the recovery rate improves.
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#114
by
edkyle99
on 31 Aug, 2016 00:01
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#115
by
gongora
on 31 Aug, 2016 00:10
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Can anyone explain the "R-023" in the current thread title (as of August 30, 2016)? Although the CRS-8 first stage did boost the 23rd flight, there is information in other threads that the booster itself is serial number "B1021". http://forum.nasaspaceflight.com/index.php?topic=40044.msg1572912#msg1572912
- Ed Kyle
Going with the number of the first flight is probably safest for now, unless we're sure we can actually find out and keep track of serial numbers for all of the recent and upcoming cores.
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#116
by
mvpel
on 31 Aug, 2016 04:19
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If your not burning any fuel... how is that a gravity loss ?...
I call that...
"coasting in an upward direction... trading velocity for altitude... while clearances improve between a 210klbs thrust rocket engine... and some rather important hardware you plan to recover..."
Compare CRS-8 at T+2:40 and Thaicom-8 Technical at T+2:43, and you'll note a very significant difference from stage separation to ignition. In the latter, the upper stage shifts the aim-point of the engine (remember the Kzinti Lesson, everyone?) well away from the booster and down towards the Earth as shown in the screenshots - an angle that is able to provide additional altitude, which it needs anyway, at the momentary expense of lateral velocity while the engine starts up and the booster gains more distance, and then it trims out and keeps on going.
I have little doubt that this maneuver was designed to substantially reduce damage to the interstage without having to spend very much time coasting:
http://forum.nasaspaceflight.com/index.php?topic=40256.msg1540860#msg1540860
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#117
by
Brovane
on 31 Aug, 2016 05:36
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Q) will the price charged for the re-flown booster go down with each re-use? $40M for 1st reuse, $30M second reuse .... Min $25M? I know Ms Shotwell said ~$40M for reflown booster, but they've never reflown one. Will cost and time spent readying boosters for reuse go down with time.
Need to call in NASCAR, F1, IndyCar, or NHRA teams for processing strategies and brainstorming sessions.
Probably not.
The overhead costs of launch - using the range, paying everyone who works there, payload integration, fuel, etc. - all stay the same. Also they are still building a new second stage every time, so there's the same overhead costs for that every time. Plus the additional costs for the first stage recovery, of shipping and testing all components, refurbishment if necessary, etc. will need to be there.
Obviously your will always have your OpeX costs, refurbishment costs and range costs for each launch along with the 2nd stage costs. However the more launches you can get out of a 1st stage, the more launches you can amortize the costs of the initial build of the 1st stage.
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#118
by
guckyfan
on 31 Aug, 2016 07:33
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IMO most importantly the value of flight 5 is not lower than flight 2. Cores will not launch if their safe operation is not ensured. So prices will not vary. Prices for first launches will be higher only as long as there are customers who insist on new cores and are willing to pay a higher price. Good for business when NASA for astronauts and DOD want new cores. It will give a constant supply of basically free cores for commercial flights.
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#119
by
AncientU
on 31 Aug, 2016 12:00
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Q) will the price charged for the re-flown booster go down with each re-use? $40M for 1st reuse, $30M second reuse .... Min $25M? I know Ms Shotwell said ~$40M for reflown booster, but they've never reflown one. Will cost and time spent readying boosters for reuse go down with time.
Need to call in NASCAR, F1, IndyCar, or NHRA teams for processing strategies and brainstorming sessions.
Probably not.
The overhead costs of launch - using the range, paying everyone who works there, payload integration, fuel, etc. - all stay the same. Also they are still building a new second stage every time, so there's the same overhead costs for that every time. Plus the additional costs for the first stage recovery, of shipping and testing all components, refurbishment if necessary, etc. will need to be there.
Obviously your will always have your OpeX costs, refurbishment costs and range costs for each launch along with the 2nd stage costs. However the more launches you can get out of a 1st stage, the more launches you can amortize the costs of the initial build of the 1st stage.
No need to amortize. First customer paid for the stage capital expense...
If we assume the boosters cost $25M each to manufacture, then the recovery/refurb cost is of order 10%... cost of one booster or so for each ten in the barn -- the situation which could exist at the end of 2016 (20 weeks from now).
Therefore, only 8-9 are officially free.
http://forum.nasaspaceflight.com/index.php?topic=40373.msg1569114#msg1569114
