Falcon Heavy to be officially launched?

On Fri, 08 Apr 2011 20:55:44 +1000, Alan Erskine
wrote:


Payloads match launcher capacity, not the other way around. Bigger LV's
mean bigger payloads.

Yes, but so far we've always had more than one launch vehicle
available. Ariane 4 always had Atlas-Centaur capable of launching the
same satellite, which gave industry a fallback position and
negotiating power. Ariane 5 always had Atlas 2 and then Atlas 3 and
Proton from ILS, and later SeaLaunch Zenit. Industry is not going to
design and build a satellite that has only one launch vehicle
available, which will be the case with Falcon Heavy.

No, they won't. None of the satellite companies will want to be
trapped doing business with the one and only company offering launch
services for somethiing that large.

They alread are - most GeoSats are launched by Ariane 5; Atlas is used
mostly by NASA and Delta IV Heavy is used mostly by NRO.

False. There are no commercial satellites launched by Ariane 5 that
cannot also be launched by SeaLaunch, Proton or Atlas 5. But if
industry builds a 10 ton GEO satellite, the only vehicle capable of
launching it will be Falcon Heavy. Whatever market Mr. Musk has in
mind, it isn't GEO Super Satellites.

If they can get it launched at much less than half the price? If they
can have it built with the same organisation as the launch vehicle
(which would mean half the price for the modules, by reasonable logic)?

Nope. There is still no particularly strong justification for a Space
Station. What little there is will hopefully be satisfied by ISS-1.
That doesn't go away because launch costs drop. Systems design and
integration is still time consuming and expensive. ISS-2 could be half
the price of ISS-1, but that is still tens of billions of dollars, and
the answer to "what do you need this for?" still begins with "Uh..."

As for Bigelow's BA 330, it only weighs that much (up to 23 tonnes)
because of the launch vehicle capabilities that existed when that
concept was first 'aired'. Why not twice as big with less cost?

Because they are then at the mercy of whatever the one and only launch
provider decides in terms of cost and schedule. No ability to say,
"Sorry, I can't pay you that much or wait that long, so I'm going to
Atlas..." No customers will deliberately put themselves in that
position.

You seem willing to talk about a Lunar program that doesn't exist, but
completely disregard the possibility of an ISS replacement?

Yes. Because the President and Congress for the past seven years have
supported BEO in one form or another (lunar, asteroid, Mars.) Congress
is even forcing NASA to build a mega rocket for it. It took serious
negotiation to get Congress to agree to extending ISS to 2020. Again,
there is absolutely no appetite on Capitol Hill for ISS-2. None
whatsoever. The next space station will be private/commercial (with
the possible exception of prop depot), and will be sized such that it
will not be dependent on one launch system, as ISS was on the Space
Shuttle.

Brian

In article , bthorn64
@suddenlink.net says...

On Wed, 6 Apr 2011 08:35:46 -0400, Jeff Findley
wrote:

Yes, but what payloads need that capacity anytime in the next decade?
Three giant GEO satellites at the same time? Good luck scheduling
that.

DOD satellites. The cost savings isn't huge (what's a billion dollars
for DOD?), but it's non-trivial.

Nope. DoD is not building satellites too large for any existing
launcher.

Agreed. However, if Falcon Heavy proves to be viable, DoD will most
definitely look at ways they can take advantage of that additional
payload capacity. If anything, they could save some money on "next
generation" satellite designs by doing things like replacing titanium
parts with cheaper, but heavier, aluminum alloys.

One of the aerospace (satellite) engineers I know say they had one
Russian guy do all of their machining of their titanium parts, because
he was the best. Buying the best of anything means higher costs. Lots
of suppliers can make precision machined parts out of aluminum alloys,
which means competition, which means lower costs.

Cheaper DoD satellites would mean they could build more of them at more
frequent intervals resulting in greater military capabilities for their
network of satellites.

Jeff
--
" Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry
Spencer 1/28/2011

On Fri, 08 Apr 2011 20:46:33 +1000, Alan Erskine
wrote:

Regardless of how economical Falcon Heavy is compared to other LV's,
SSPS is completely uneconomical compared to just bolting PV (Solar
panels to most people) onto every roof and connecting them to the Grid.

What do you do at night and on cloudy days?

Brian

In article , bthorn64
@suddenlink.net says...

On Fri, 08 Apr 2011 20:55:44 +1000, Alan Erskine
wrote:


Payloads match launcher capacity, not the other way around. Bigger LV's
mean bigger payloads.

Yes, but so far we've always had more than one launch vehicle
available. Ariane 4 always had Atlas-Centaur capable of launching the
same satellite, which gave industry a fallback position and
negotiating power.

That negotiating power was used to negotiate lower prices for launching
those satellites. Falcon Heavy is going to be priced so much cheaper
than the competition, that negotiating launch costs is moot.

Jeff
--
" Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry
Spencer 1/28/2011

In article , bthorn64
@suddenlink.net says...

On Fri, 08 Apr 2011 20:46:33 +1000, Alan Erskine
wrote:

Regardless of how economical Falcon Heavy is compared to other LV's,
SSPS is completely uneconomical compared to just bolting PV (Solar
panels to most people) onto every roof and connecting them to the Grid.

What do you do at night and on cloudy days?

Electricity is cheaper at night anyway (electric customers generally
draw more power during the day). On cloudy days, the electric companies
will fire up more generators to meet the demand.

Jeff
--
" Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry
Spencer 1/28/2011

In sci.space.shuttle message ,
Wed, 6 Apr 2011 08:35:46, Jeff Findley
posted:


Not the same thing at all. Cross-fed propellants needs three sets of
valves for the core stage engines. One between the core engines and the
core tanks, one between the core engines and the left booster, and one
between the core engines and the right booster.

The tricky bit is the transition between having the core engines fed by
the booster tanks and having the core engines fed by the core tanks.
Pressure transients in the lines could be an issue. You *really* don't
want your turbopumps to suck gas, because if they do they overspeed and
go *boom*. That's one of the most violent failure modes of a liquid
turbopump fed rocket engine.


In principle, all that is needed is the standard fuel feeds for each of
the three F9 units, plus pumps and plumbing in the outer two F9s to keep
the central F9's tanks topped up. If the transferred propellant is
piped in at the top, valves are only needed to maintain any
pressurisation in the central F9 after separation (and perhaps for
floating the outer F9s).

This should have been injected on 2011-04-07 Fri, but my ISP was ill.

--
(c) John Stockton, nr London, UK. Turnpike v6.05 MIME.
Web http://www.merlyn.demon.co.uk/ - FAQqish topics, acronyms and links;
Astro stuff via astron-1.htm, gravity0.htm ; quotings.htm, pascal.htm, etc.
No Encoding. Quotes before replies. Snip well. Write clearly. Don't Mail News.

On 8/04/2011 11:51 PM, Jeff Findley wrote:
In , bthorn64
@suddenlink.net says...

On Wed, 6 Apr 2011 08:35:46 -0400, Jeff Findley
wrote:

Yes, but what payloads need that capacity anytime in the next decade?
Three giant GEO satellites at the same time? Good luck scheduling
that.

DOD satellites. The cost savings isn't huge (what's a billion dollars
for DOD?), but it's non-trivial.

Nope. DoD is not building satellites too large for any existing
launcher.

Agreed. However, if Falcon Heavy proves to be viable, DoD will most
definitely look at ways they can take advantage of that additional
payload capacity. If anything, they could save some money on "next
generation" satellite designs by doing things like replacing titanium
parts with cheaper, but heavier, aluminum alloys.

Also, in the case of reconsats, it means longer lives - they live a
precarious existance and eventually burn up in the atmosphere after only
a couple of years.

On 8/04/2011 11:54 PM, Brian Thorn wrote:
On Fri, 08 Apr 2011 20:46:33 +1000, Alan Erskine
wrote:

Regardless of how economical Falcon Heavy is compared to other LV's,
SSPS is completely uneconomical compared to just bolting PV (Solar
panels to most people) onto every roof and connecting them to the Grid.

What do you do at night and on cloudy days?

Brian

At night, electricity consumption is much lower (I'm studying renewable
energy at the moment and will be making it my career within the next 12
months).

Also, there are (albeit expensive) storage systems available for storing
enough for such circumstances.

There are also other sources of renewable energy available, including
biomass for powerstations (if they only need biomass for night-time
consumption, then the amount needed is much, much smaller).

On the other hand, if we have SSPS's, what do we do during eclipses?
All of a sudden, the whole grid closes down for several minutes.

On 8/04/2011 11:50 PM, Brian Thorn wrote:
On Fri, 08 Apr 2011 20:55:44 +1000, Alan Erskine
wrote:


Payloads match launcher capacity, not the other way around. Bigger LV's
mean bigger payloads.

Yes, but so far we've always had more than one launch vehicle
available. Ariane 4 always had Atlas-Centaur capable of launching the
same satellite, which gave industry a fallback position and
negotiating power. Ariane 5 always had Atlas 2 and then Atlas 3 and
Proton from ILS, and later SeaLaunch Zenit. Industry is not going to
design and build a satellite that has only one launch vehicle
available, which will be the case with Falcon Heavy.

No, they won't. None of the satellite companies will want to be
trapped doing business with the one and only company offering launch
services for somethiing that large.

They alread are - most GeoSats are launched by Ariane 5; Atlas is used
mostly by NASA and Delta IV Heavy is used mostly by NRO.

False. There are no commercial satellites launched by Ariane 5 that
cannot also be launched by SeaLaunch, Proton or Atlas 5. But if
industry builds a 10 ton GEO satellite, the only vehicle capable of
launching it will be Falcon Heavy. Whatever market Mr. Musk has in
mind, it isn't GEO Super Satellites.

Yes, but Ariane also launches two satellites at once - why not launch
four at once? The only problem with that will be reliability, and that
doesn't seem to be much of a problem with the Falcon 9 and it's derivatives.

On Sat, 09 Apr 2011 08:10:09 +1000, Alan Erskine
wrote:


False. There are no commercial satellites launched by Ariane 5 that
cannot also be launched by SeaLaunch, Proton or Atlas 5. But if
industry builds a 10 ton GEO satellite, the only vehicle capable of
launching it will be Falcon Heavy. Whatever market Mr. Musk has in
mind, it isn't GEO Super Satellites.

Yes, but Ariane also launches two satellites at once

Not always, and the forthcoming Ariane 6 will be back to one-at-a-time
launches, because it was getting too complicated finding two suitable
payloads that would be ready at the same time. Ariane 5 can't launch
two of the Big GEO satellites at once, so they have to find a Big GEO
and a Medium GEO ready at the same time (and even that has required
costly improvements). And with satellites living longer and longer,
replacement launches are much less common than they were when Ariane 5
was developed, so now Arianespace is between a rock and a hard place.

why not launch four at once?

NASA tried that (three and four at a time) with the Shuttle and
quickly ran into serious problems getting multiple payloads together
at the same time, and when schedules slipped because of it, critics
complained mercilessly about NASA failing to meet its schedules.
Ariane has to launch five or six times a year to break even (depending
on which numbers you believe), but matching payloads is making that
more and more difficult. Falcon Heavy should be able to launch two Big
GEO satellites easily, perhaps even three. But how often are such
satellites launched? How many times a year will Falcon Heavy need to
launch to break even? How will Falcon Heavy pay for itself in the long
gaps between having 2 or 3 Big GEOs ready for launch? SpaceX can't use
Falcon Heavy to spark a huge increase in the numbers of Big GEOs,
because there is a limited number of GEO slots, most already occupied.

The only problem with that will be reliability, and that
doesn't seem to be much of a problem with the Falcon 9 and it's derivatives.

Wow, high praise for a rocket with two launches under its belt
(Shuttle was perfect the first 24 times, remember.) I like Falcon 9
and Falcon Heavy, I really do (Falcon 1 is another matter) but it is
still an expendable rocket and it still has to live within the same
laws of physics as everyone else. It is unlikely to do better than 99%
reliability, and its Falcon 1 heritage suggests less than that. Even
for a cheap rocket, that's going to be an expensive failure when the
odds catch up with Falcon Heavy.

Brian