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Old October 29th 17, 03:30 PM posted to sci.space.policy
Jeff Findley[_6_]
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Posts: 2,307
Default Were liquid boosters on Shuttle ever realistic?

In article . com,
says...

On 2017-10-28 15:38, Jeff Findley wrote:

So what? They're doing better at turning around recovered first stages
to be re-flown faster than any of the competition


The only "re-use" competition is the Shuttle and it wasn't a commercial
endeavour.


The space shuttle isn't competition, because every single orbiter is in
a museum! SpaceX currently has zero (operational) competition when it
comes to reusing flown first stages from orbital launches.

Landing a just launched stage doesn't save any money. It costs money.


Relative to the cost of manufacturing a new first stage, there is very
little cost associated with recovering flown first stages. You're just
being daft at this point.

Launching a payload with a re-used stage 1 is what saves you money.


Yes, and customers are switching to flown first stages in order to
launch their payloads sooner. I've told you this several times now.
But here is a cite since you seem unwilling to Google this yourself:

Iridium swaps two new Falcon 9 rockets for ?flight-proven? boosters
October 20, 2017 Stephen Clark
https://spaceflightnow.com/2017/10/2...-new-falcon-9-
rockets-for-flight-proven-boosters/


The Block 5 has improvements to the design to help with reuse.


One could infer that those improvements are a sign that the current
Falcon 9 is harder to re-use as the cheer leaders say it is.


Bull****. Again, the first reuse cost them half the cost of building a
new first stage. It's a proven fact that they're saving money with
every used stage that is reflown. Yes, they're making improvements to
make reuse easier and more economical, but the fact is that it's
economical right now, even with the Block 3's that are only going to be
reflown once each.

SpaceX
will only get better at this while the competition (aside from Blue
Origin, who's still working on the BE-4 engine for New Glenn) are not
even trying to reuse anything.


The argument isn't whether SpaceX is ahead or other or not. The mere
fact that they have demonstrated they can land a stage, and have re-used
at least 1 stage means they are way ahead of anyone else.

But that doesn't mean that they have proven that they can already
quickly turn around every landed Falcon 9.


So what? They're saving money on recovered stage that is reflown.
That's what counts here. You're damning them because they're not yet to
the "gas and go" stage even though they're the only company reflying
stages and saving money doing it.

That makes zero sense. Who the hell ****ed in your Cheerios?

They've demonstrated the concept, they've demonstrated they can land
stages, they have demonstrated they can refly at least 1 stage. But
havent yet demonstrated they can have short turn around between landing
pad and launch pad such that it allows high launch rate OF RE-USED STAGES.

Just because it is very likely that they will be able to turn these
around quickly doesn't translate to them having demonstrated it.

Just because there are improvements coming that will make future refurb
even easier doesn't mean that they have demonstrated it already.


What they have now is still better than anyone else in the industry.

The crush core is more likely to be used up on high energy launches.


On a commecial aircraft, after a hard landing, the aircraft is put "off
line" for inspections. So I would assume that if a crush core gets used
up fully, the stage may require more time to be certified for reflight.

I am not questioning the huge game changing advantage SpaceX has in
having developped re-usable stages. Am not questioning that they have
proven they can land stages and re-use at least 1.

What they haven't proven yet is the ability to ramp up refurbishement to
do quick turn around from landing pad to launch pad. It's too early for
them to have demonstrated it.


This is the eventual goal. Every refurbish and reflight they make gives
them more data on how to do things better. Even if they never quite
make it there with Falcon 9 and Falcon Heavy, there is always BFR.

At least they're trying. Blue Origin is the only other company trying,
and they're still working on developing their BE-4 engine which they
need for their orbital New Glenn launch vehicle. No other launch
company (or government) on the planet is even attempting to do what
SpaceX is doing today.

I just don't get why you're ****ing on their unprecedented
accomplishments. What's your point?

Jeff
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