Spacelink? Bad luck!

GWGeorge007
GWGeorge007
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Topic 226943
archae86
archae86
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SpaceX often walks pretty

SpaceX often walks pretty close to the edge, and once in a while they lose the bet.

I can recall two first-stage landings which failed because not quite enough of a consumable fluid was placed on board.  For an early attempted landing it was fluid needed for the single-pass hydraulic system powering the grid fines.  Much later a Super Heavy center booster crashed because an engine failed to light, for want of enough lighter fluid.

This time it was a question of setting initial orbital altitude just barely high enough so that atmospheric drag would not bring the birds down before they could boost themselves up.  Low has two advantages: it requires less oomph from the booster, so at some boundary makes the difference of launching one more satellite.  The another advantage is that a low initial orbit means rapid clearing by destructive de-orbit in the case of a satellite failure.

The trouble this time is that mother nature changed the terms of the game, as the atmospheric density at the altitude of interest went up quite a bit.

I imagine in the future SpaceX will try to improve their space weather forecast quality and response.  Just maybe they'll launch one fewer satellite in a given configuration, as they may not prefer to make rapid payload configuration changes or delay launches when the space weather is bad.

 

GWGeorge007
GWGeorge007
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I wouldn't have realized the

I wouldn't have realized the he (Musk) would have been so mindless as to not be putting up a rocket with minimal fuel to weather some issues as what just happened.  It is too bad, but at the same time, I think he needs a lesson or three to make SpaceX work a little better.

George

A proud member of the O.F.A. (Old Farts Association)

mikey
mikey
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GWGeorge007 wrote: I

GWGeorge007 wrote:

I wouldn't have realized the he (Musk) would have been so mindless as to not be putting up a rocket with minimal fuel to weather some issues as what just happened.  It is too bad, but at the same time, I think he needs a lesson or three to make SpaceX work a little better. 

He's always seemed to me as a genius eccentric billionaire who needs to wear slip-on shoes because he can't remember to tie them. ie the guy who has brilliant ideas and then tells his people 'make it happen' who then have to try and figure out what the heck the guy was even talking about let alone how to implement it.

Mike Hewson
Mike Hewson
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Maybe more time playing

Maybe more time playing Kerbal Space Program will help ! ;-)

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

Gary Charpentier
Gary Charpentier
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He's paying for his own

He's paying for his own launches, so a few hundred pounds of propellant is a few $$$ out of his pocket and he is still losing money at a good burn rate.  Don't know if he bought launch insurance or just assumed the risk himself. 

mikey
mikey
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Gary Charpentier wrote: He's

Gary Charpentier wrote:

He's paying for his own launches, so a few hundred pounds of propellant is a few $$$ out of his pocket and he is still losing money at a good burn rate.  Don't know if he bought launch insurance or just assumed the risk himself. 

He's also based in the US so any business losses are tax deductible against any money he made, he said a month or so ago that he owes over 3 Billion US Dollars in taxes this year alone. Now how much of that he actually has to pay is up to his accountants of which I assume he has some pretty good ones.

Gary Charpentier
Gary Charpentier
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mikey wrote: Gary

mikey wrote:

Gary Charpentier wrote:

He's paying for his own launches, so a few hundred pounds of propellant is a few $$$ out of his pocket and he is still losing money at a good burn rate.  Don't know if he bought launch insurance or just assumed the risk himself. 

He's also based in the US so any business losses are tax deductible against any money he made, he said a month or so ago that he owes over 3 Billion US Dollars in taxes this year alone. Now how much of that he actually has to pay is up to his accountants of which I assume he has some pretty good ones.

Yes, but no.  Pay from Tesla can't offset a loss at SpaceX.  Only offset is when he sells stock, and since his basis is near zero anyway ...  To him personally.

Ian&Steve C.
Ian&Steve C.
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I doubt spaceX does any

I doubt spaceX does any in-house space weather forecasting or prediction. They likely just use the same predictions given to those of us in the space industry, it’s available freely on the web. No need to re-invent the wheel. The problem is that the space weather and atmospheric density is mostly at the whim of solar activity, which is only barely predictable on the general 11 year solar cycles. Huge spikes in solar activity come out of no where, even when the future prediction shows very low activity. 
 

Source: 12+ years working in satellite operations and collision avoidance for LEO NASA missions. Starlink causes a lot of conjunction issues for both GPM and IceSat-2. OneWeb is also troublesome for LEO. Lots of companies trying to get their slice of the satellite internet pie. 

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archae86
archae86
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The Starlink launch currently

The Starlink launch currently scheduled for this coming Sunday is planned for 46 satellites, a southern launch azimuth, and a higher initial orbital injection than was used for the problem launch.  (325 km for initial perigee)

So it appears they have taken birds off the bus in order to put themselves a bit farther from the excess drag boundary.

By way, the scale height of Earth's atmosphere is a bit under 10 km, so a little extra distance up gives quite a benefit in drag reduction.

 

 

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