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Future of Falcon Heavy



 
 
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  #1  
Old February 10th 18, 02:16 PM posted to sci.space.policy
Jeff Findley[_6_]
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Posts: 2,307
Default Future of Falcon Heavy

In article ,
says...

On 2018-02-09 17:33, Greg (Strider) Moore wrote:

http://www.thespacereview.com/article/3423/1

I think it's relevant to your question.



OK, so Falcon Heavy is a niche market to serve DoD and a few others.

Would be interesting to ask Musk if, in hindsight, it turned out cheaper
to work on strapping 3 Falcon 9s together versus packaging Falcon9
components (engines, tanks etc) into a single core). Isn't it simpler to
strap the tanks together than to deal with booster sepatation?


No. SpaceX found that it is much harder to do parallel loading,
parallel ignition, parallel aerodynamics, and parallel staging than it
was to do a "single stick" vehicle. There are many Elon Musk quotes
which essentially says that Falcon Heavy was, in fact, much harder than
they thought it would be. So much so that they almost canceled it 3
different times according to Musk.

Look, Falcon Heavy reportedly cost $500 million to develop, has a $90
million per launch list price, and it's playing in a market where it
might get 2-3 launches per year. If everything goes according to Musk's
plans it will be replaced by BFR/BFS in maybe 5 years (possibly
optimistic). So, spread $500 million over 15 launches of Falcon Heavy
during that time and you get $33 million, which is over 1/3 of the list
price of Falcon Heavy (ouch). Add in interest over those years and it's
an even higher percentage of the list price.

How in the hell is it ever going to make back that R&D investment with
those numbers? My guess is that it simply won't. It's a technological
dead end, just like Falcon 9. BFR/BFS, a fully reusable TSTO, is
planned to eventually replace them both.

Musk had repeatedly stated that they had grossly underestimated how much
work was needed to strap the 3 stages together.


Well that answers your question above, doesn't it?

Someone mentioned that musk won't bother man-rating Falcon Heavy.
(despite mentions elswhere of "joy rides around the moon" in Dragon).

Since it shares some much commonality with Falcon 9, including common
stage 2, capsule escape system, common stage 1 engines and I assume
much commonality in software, how difficult would it be to man rate
Falcon Heavy once Falcon 9 gets its man rating certification ?


It's hard to say how much of this is hard fact and how much of this is
marketing (i.e. product differentiation). BFR/BFS needs funding and was
always intended to be "man rated" from the very beginning. It's hard to
get a few $billion from investors to finish BFR/BFS development when
Falcon Heavy is already flying and can handle the "high end" of the
existing markets. To some investors (hopefully none that actually have
money in SpaceX), now is the time to stop developing new hardware and
turn SpaceX into a cash cow ala ULA (e.g. Atlas V, Delta IV, and Delta
Heavy).

Jeff
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All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
  #2  
Old February 10th 18, 11:40 PM posted to sci.space.policy
Fred J. McCall[_3_]
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Posts: 10,018
Default Future of Falcon Heavy

JF Mezei wrote:

On 2018-02-10 08:16, Jeff Findley wrote:

No. SpaceX found that it is much harder to do parallel loading,
parallel ignition, parallel aerodynamics, and parallel staging than it
was to do a "single stick" vehicle.


Was this a necessary "growing up" step needed for SpaceX to realize this
and reset it plans, going for the single bigger stick *BFR) ?

In other words, had they not had the difficulties with Falcon Heavy,
would BFR have been conceived ?


BFR was 'conceived' long before Falcon Heavy had any difficulties. The
actual timeline answers your question.


How in the hell is it ever going to make back that R&D investment with
those numbers? My guess is that it simply won't. It's a technological
dead end, just like Falcon 9.


Didn't SpaceX develop many skills in terms of structures, load handling
etc that would have value for future projects such as BFR?


Not really, no.


And even that first flight, the data from the (attempted) landings of
the stages is bound to be of use in terms of comparing performance of
the heavy "tubes" with the 9 "tubes". (Musk mentioned that the cone atop
boosters made a big difference in terms of aerodynamic authority of
paddles, greatly increasing difficulty).


All data is of use, even if it's data that tells you something can't
work.



BFR/BFS, a fully reusable TSTO, is
planned to eventually replace them both.


I have my doubts that BFR will replace Falcon 9. I get the impression
that the 9 is the right size for vast majority of payloads and BFR is
overblown.


But when you look at costs BFR is *A LOT* cheaper.


Just as there are complaints about the shuttle being too heavy for what
it carried, I suspect BFR will be way too heavy if it only goes to ISS
to carry 3 or 4 crewmembers. Like a 747 being used to carry just a
handful of people.


So why would you even have that mission? You'd bring 3 astronauts
plus however many tons of cargo you might want to launch. Fewer
bigger resupply missions. Again, BFR is *MUCH CHEAPER* than Falcon 9
launches to do even an approximately equivalent mission. Musk thinks
BFR Spaceship can compete at the high end of high speed air transport.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn
  #3  
Old February 11th 18, 03:28 PM posted to sci.space.policy
Jeff Findley[_6_]
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Posts: 2,307
Default Future of Falcon Heavy

In article ,
says...

On 2018-02-10 08:16, Jeff Findley wrote:

No. SpaceX found that it is much harder to do parallel loading,
parallel ignition, parallel aerodynamics, and parallel staging than it
was to do a "single stick" vehicle.


Was this a necessary "growing up" step needed for SpaceX to realize this
and reset it plans, going for the single bigger stick *BFR) ?


Not in my opinion. The only bits unique to Falcon Heavy have nothing to
do with BFR/BFS which will be "single stick" just like Falcon 9. Again,
Falcon Heavy is a technological dead end on the road to fully reusable
TSTO, which is the ultimate goal of SpaceX. Strap-ons add complexity
and therefore cost, which is why BFR/BFS has none.

In other words, had they not had the difficulties with Falcon Heavy,
would BFR have been conceived ?


BFR/BFS was conceived of well before the extent of the difficulties with
Falcon Heavy were fully known.

How in the hell is it ever going to make back that R&D investment with
those numbers? My guess is that it simply won't. It's a technological
dead end, just like Falcon 9.


Didn't SpaceX develop many skills in terms of structures, load handling
etc that would have value for future projects such as BFR?


Nope. They did all of that with Falcon 9 which is "single stick" like
BFR/BFS. Things that are different, just aren't the same. BFR/BFS is
fundamentally more like Falcon 9 than Falcon Heavy.

And even that first flight, the data from the (attempted) landings of
the stages is bound to be of use in terms of comparing performance of
the heavy "tubes" with the 9 "tubes". (Musk mentioned that the cone atop
boosters made a big difference in terms of aerodynamic authority of
paddles, greatly increasing difficulty).


Depends if BFR has both grid fins and a nose cone on top, doesn't it?

BFR/BFS, a fully reusable TSTO, is
planned to eventually replace them both.


I have my doubts that BFR will replace Falcon 9. I get the impression
that the 9 is the right size for vast majority of payloads and BFR is
overblown.


Who cares how big it is? The only thing that matters is if the launcher
can place the payload in the right orbit and what it will cost the
customer.

If BFR/BFS turns out to be as reusable as it is intended, the marginal
cost of launching a Falcon 9 sized payload is the cost of the
LOX/methane propellant plus a tiny cost to inspect and stack the thing
before launch. Nearly airline like operations will mean picking a
launch vehicle based on the cost, not the max payload of the vehicle.

Bonus points if BFR/BFS has intact abort modes throughout the launch.
Given the number of engines on BFR and BFS, I'd say it most likely will.
Note that a single engine failure on Falcon's upper stage ends the
mission and results in either partial failure (e.g. wrong orbit) or
complete failure (e.g. payload splashing down in the ocean). This has
the potential to turn what would have been a "launch failure" in the
past into more of a "launch delay" for the customer.

Just as there are complaints about the shuttle being too heavy for what
it carried, I suspect BFR will be way too heavy if it only goes to ISS
to carry 3 or 4 crewmembers. Like a 747 being used to carry just a
handful of people.


The primary problem with the shuttle was its high cost. Total program
cost divided by total number of flights gives $1.45 billion. That's too
damn high, so yes one way to reduce cost/lb to LEO would have been to
ditch the orbiter and go with something like Shuttle-C. But the high
costs would still have been there, so there is a hard limit to how much
you can reduce costs by shaving mass off your launch vehicle.

SpaceX reduces costs by focusing on reducing cost from the very
beginning. Even in fully expendable mode, Falcon 9 and Falcon Heavy are
far cheaper than the other alternatives offered by ULA.

BFR/BFS will necessarily be more expensive, but SpaceX is betting it
will be "truly reusable" with "gas and go" like operations. No
disposable upper stages, no disposable fairings (although SpaceX is
working on recovering them), and best of all, I'm betting we see no more
barge landings. Launching BFR/BFS from an offshore platform for use as
a high speed transport is marketing, IMHO. My bet is we'll see BFR/BFS
launch from pads on land and land again on landing pads in Florida,
California, and Texas.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
  #4  
Old February 11th 18, 03:32 PM posted to sci.space.policy
Jeff Findley[_6_]
external usenet poster
 
Posts: 2,307
Default Future of Falcon Heavy

In article ,
says...

Just as there are complaints about the shuttle being too heavy for what
it carried, I suspect BFR will be way too heavy if it only goes to ISS
to carry 3 or 4 crewmembers. Like a 747 being used to carry just a
handful of people.


So why would you even have that mission? You'd bring 3 astronauts
plus however many tons of cargo you might want to launch. Fewer
bigger resupply missions. Again, BFR is *MUCH CHEAPER* than Falcon 9
launches to do even an approximately equivalent mission. Musk thinks
BFR Spaceship can compete at the high end of high speed air transport.


And as a bonus, BFS could boost the orbit of ISS without relying on the
Russians. IMHO, BFR/BFS has the potential to allow the US to give the
Russians the middle finger when it comes to ISS. They want to leave and
take their modules with them? Good riddance! With the money that
BFR/BFS would allow NASA to save, stick a Bigelow Aerospace expandable
module in place of the tiny Russian aluminum cans.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
 




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