SpaceX News

Point out news stories, on the net or in mainstream media, related to polywell fusion.

Moderators: tonybarry, MSimon

hanelyp
Posts: 2230
Joined: Fri Oct 26, 2007 8:50 pm

Re: SpaceX News

Postby hanelyp » Fri May 11, 2018 5:19 pm

If a second stage is recoverable, return to launch site about a day after liftoff isn't difficult. Just wait in orbit until the launch site again approaches the orbital ground-path. Return to launch site after a single orbit is harder, especially from high inclination orbits. Recovering a second stage in good shape so it doesn't need lots of time and expense to reuse, without a heavy heat shield eating most of the payload, that's (edit) not so easy.

(somehow my keyboard doesn't always do what I type)
Last edited by hanelyp on Fri May 11, 2018 9:50 pm, edited 1 time in total.
The daylight is uncomfortably bright for eyes so long in the dark.

Maui
Posts: 534
Joined: Wed Apr 09, 2008 12:10 am
Location: Madison, WI

Re: SpaceX News

Postby Maui » Fri May 11, 2018 5:34 pm

TDPerk wrote:Less ground crew and far less expensive fuel. Also, 100 minimum launches before refitting means the not10x R&D cost is spread over far more flights.

Fuel cost is only a little higher for far more capacity.
Ground crew cost is far lower.
R&D $$$ to be amortized per flight is far lower.

Total cost to fly is lower.


Why less ground crew? I would think it would be easier to get an F9 block 6 to 100x than BFR if that was your main goal. As it stands, they probably have to learn a lot of lessons with BFR first that they've already learned with F9. And I would think scale only makes that more difficult.

It only makes sense to start flying BFR a ton once it costs less than F9. But will that happen if they are not flying BFR a ton?

paperburn1
Posts: 2343
Joined: Fri Jun 19, 2009 5:53 am
Location: Third rock from the sun.

Re: SpaceX News

Postby paperburn1 » Tue May 22, 2018 7:57 am

Saw the Orbital ATK Antares rocket over Virginia last morning, very cool cloud formation because of the rockets passage and today at 3:30 ish spacex will "yawn" launch again. on of the last few block 4 experienced stages.
prepare to be bored.
I am not a nuclear physicist, but play one on the internet.

TDPerk
Posts: 949
Joined: Mon Jul 30, 2007 12:55 pm
Location: Northern Shen. Valley, VA
Contact:

Re: SpaceX News

Postby TDPerk » Tue May 22, 2018 1:29 pm

Maui wrote:
TDPerk wrote:Less ground crew and far less expensive fuel. Also, 100 minimum launches before refitting means the not10x R&D cost is spread over far more flights.

Fuel cost is only a little higher for far more capacity.
Ground crew cost is far lower.
R&D $$$ to be amortized per flight is far lower.

Total cost to fly is lower.


Why less ground crew? I would think it would be easier to get an F9 block 6 to 100x than BFR if that was your main goal. As it stands, they probably have to learn a lot of lessons with BFR first that they've already learned with F9. And I would think scale only makes that more difficult.

It only makes sense to start flying BFR a ton once it costs less than F9. But will that happen if they are not flying BFR a ton?


Because it will cost less when flown as often as the F9 and FH together, they will fly it at that rate and have lower costs.
molon labe
montani semper liberi
para fides paternae patria

Maui
Posts: 534
Joined: Wed Apr 09, 2008 12:10 am
Location: Madison, WI

Re: SpaceX News

Postby Maui » Tue May 22, 2018 7:25 pm

You missed my point:

Given:
Keys to BFR being cheaper than F9 =
1) Full re-usability
2) High volume of launches
3) Re-usability without refurb across 100x launches

...and given:
Stated goals of block 5 =
1) Full re-usability
2) High volume of launches
3) Re-usability without refurb across 10x launches

F9 is therefore planned to acquire 2.5 of the 3 key features that was to make BFR cheaper than F9. It stands to reason that if both systems achieved all 3, F9 will be cheaper as a matter of scale, but also by virtue of the fact that F9 will have such a big headstart on achieving the 3 keys to being cheapest.

If by the time BFR is ready for full scale usage, F9 has achieved the above goals does it really make sense to start spending a lot more per launch over a period of years to get to the point where the cost of BFR is < F9? Factor in it stands to reason that the costs needed to go from block 5 to a block 6 that accomplishes all 3 would certainly pale in comparison to BFR development.

My point is that the suggestion that from a strictly financial sense, the argument that BFR is cheaper is blown up. They can still get to BFR costing less than F9, but only after spending a lot more money than they would have had to with further dev of F9. I suppose this all goes back to the reason SpaceX will stay private until they get to Mars so investors don't simply go with the option that makes SpaceX the most money.

paperburn1
Posts: 2343
Joined: Fri Jun 19, 2009 5:53 am
Location: Third rock from the sun.

Re: SpaceX News

Postby paperburn1 » Tue May 22, 2018 9:12 pm

The falcon 9 or heavy do not fulfill the mars/ moonraker 8) roll that NASA has envisioned. I will take the support of a government to have a new colony on mars and I feel the BFR is the only way NASA will get on board with the program. Once NASA figures out they can launch probes using the BFR they will have loads of cash for exploration. And hopefully the SLS will go the way of the Dodo bird.
There is a place in the world for both BFR and falcon block five. The fact the new octaweb is bolted together speaks loads on the long term reusability plans.
I am not a nuclear physicist, but play one on the internet.

kunkmiester
Posts: 862
Joined: Thu Mar 12, 2009 3:51 pm
Contact:

Re: SpaceX News

Postby kunkmiester » Wed May 23, 2018 12:26 am

Maui wrote:You missed my point:

Given:
Keys to BFR being cheaper than F9 =
1) Full re-usability
2) High volume of launches
3) Re-usability without refurb across 100x launches

...and given:
Stated goals of block 5 =
1) Full re-usability
2) High volume of launches
3) Re-usability without refurb across 10x launches

F9 is therefore planned to acquire 2.5 of the 3 key features that was to make BFR cheaper than F9. It stands to reason that if both systems achieved all 3, F9 will be cheaper as a matter of scale, but also by virtue of the fact that F9 will have such a big headstart on achieving the 3 keys to being cheapest.

If by the time BFR is ready for full scale usage, F9 has achieved the above goals does it really make sense to start spending a lot more per launch over a period of years to get to the point where the cost of BFR is < F9? Factor in it stands to reason that the costs needed to go from block 5 to a block 6 that accomplishes all 3 would certainly pale in comparison to BFR development.

My point is that the suggestion that from a strictly financial sense, the argument that BFR is cheaper is blown up. They can still get to BFR costing less than F9, but only after spending a lot more money than they would have had to with further dev of F9. I suppose this all goes back to the reason SpaceX will stay private until they get to Mars so investors don't simply go with the option that makes SpaceX the most money.


Do you need more guys at computers in mission control for BFR versus Falcon 9? Ground crew shouldn't scale with volume either, so per ton launched, savings should scale. It's more cars on the train, and hooking on the extra locomotive doesn't necessarily mean another engineer.

I think the tree is getting lost in the forest here, a BFR will carry multiple payloads, and it's the mass cost that's important, not just the cost of the rocket.
Evil is evil, no matter how small

hanelyp
Posts: 2230
Joined: Fri Oct 26, 2007 8:50 pm

Re: SpaceX News

Postby hanelyp » Wed May 23, 2018 1:06 am

paperburn1 wrote:The falcon 9 or heavy do not fulfill the mars/ moonraker 8) roll that NASA has envisioned. I will take the support of a government to have a new colony on mars and I feel the BFR is the only way NASA will get on board with the program. Once NASA figures out they can launch probes using the BFR they will have loads of cash for exploration. And hopefully the SLS will go the way of the Dodo bird.
There is a place in the world for both BFR and falcon block five. The fact the new octaweb is bolted together speaks loads on the long term reusability plans.

My impression is that with the availability of orbital refueling a Falcon Heavy based stack could deliver towards Mars any payload it could lift into a stable Earth orbit, which is a whole lot more than you could do with SLS, which will never fly enough times for orbital refueling to be viable.
The daylight is uncomfortably bright for eyes so long in the dark.

ladajo
Posts: 6167
Joined: Thu Sep 17, 2009 11:18 pm
Location: North East Coast

Re: SpaceX News

Postby ladajo » Wed May 23, 2018 12:08 pm

BFR will carry multiple payloads, and it's the mass cost that's important, not just the cost of the rocket.


This is a key point. The true metric is in cost per lb to orbit.

The other main point is that they serve TWO DIFFERENT mission sets. While BFR can service the Falcon 9 mission set, Falcon 9 will not ever be able to service the main mission set for BFR (return travel beyond orbit). It is comparing apples and oranges for this perspective.

Also, as a minor point, as I understand, there will be no "Block 6 Falcon 9". They have capped the program at Block 5. There may be some 5.1, or 5.1.1 stuff, however, I am pretty darn sure that they came out and said end of the design train for Falcon.
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)
What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)

Maui
Posts: 534
Joined: Wed Apr 09, 2008 12:10 am
Location: Madison, WI

Re: SpaceX News

Postby Maui » Wed May 23, 2018 4:58 pm

ladajo wrote:Also, as a minor point, as I understand, there will be no "Block 6 Falcon 9". They have capped the program at Block 5. There may be some 5.1, or 5.1.1 stuff, however, I am pretty darn sure that they came out and said end of the design train for Falcon.

Absolutely no disagreement there; block 6 was just a hypothetical to counter the idea that BFR cost < F9 cost. I absolutely think that the [total program cost from this point] / [total $ in future launch revenue] would be significantly less if they did create a block 6 capable of 100x launches without refurb.

In terms of BFR serving all launches, how practical would it be to have line up half a dozen payloads in similar orbits to be launched together and still deliver timely launches for customers? That would require an immense volume of launches that I'm not sure is feasible from orbit space requirements once one or two fleets like Starlink are up. I suppose this is where Earth-to-Earth comes into play-- the only feasible way to have enough flight frequency in the long run so that BFR make sense from a cost perspective. Outside of that, even with moon/mars missions, I have a really hard time believing BFR is the most cost effective overall solution for all launches.

ladajo
Posts: 6167
Joined: Thu Sep 17, 2009 11:18 pm
Location: North East Coast

Re: SpaceX News

Postby ladajo » Wed May 23, 2018 7:32 pm

It is an interesting question, and seems to lay on a foundation of how often will BFR push, and can it support mixed missions? Ie. LEO/HEO/GEO deliveries in addition to Moon/Lagrange/Mars/Belt servicing.

There is enough work, in my opinion, that payload stacking would be sufficient to enable less launches per calendar day. The other point here is that an entirely new orbital payload regime is opened up with BFR. This in turn will present an, until now, unseen size/capability of satellite or space station component(s). In addition, there is some argument to be made that customers will be willing to cost share on a BFR launch, and schedule accordingly. This is already happening on existing boosters.
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)

What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)

Aero
Posts: 1188
Joined: Mon Jun 30, 2008 4:36 am
Location: 92111

Re: SpaceX News

Postby Aero » Wed May 23, 2018 9:41 pm

It is also notable that BFR has the capacity to LEO to launch multiple payloads that include kick motors. Such a configuration would allow the payloads to reach high orbits and perhaps some degree of plane change maneuvers. Added payload complexity is the downside of course.
Aero

paperburn1
Posts: 2343
Joined: Fri Jun 19, 2009 5:53 am
Location: Third rock from the sun.

Re: SpaceX News

Postby paperburn1 » Mon Jun 04, 2018 12:55 pm

Yawn, so boring we are not even watching any more.
Falcon 9's first-stage engines ignited at 12:45 a.m. EDT (GMT-4), generating a torrent of fiery exhaust and thick clouds of steam before vaulting away from pad 40 at the Cape Canaveral Air Force Station.
I am not a nuclear physicist, but play one on the internet.

ladajo
Posts: 6167
Joined: Thu Sep 17, 2009 11:18 pm
Location: North East Coast

Re: SpaceX News

Postby ladajo » Mon Jun 04, 2018 2:44 pm

Well, being fair, it was a punted launch that ended up in the wee hours. I did watch the replay this morning. Very pretty night launch.
Somewhere out there are some unhappy fish from the 1st Stage disposal.

Next up is a block V I think. I believe NASA wants SpaceX to launch 10 of them prior to authorizing manned certification.

I am looking forward to the next Heavy launch in the fall (if it doesn't slip).
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)

What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)

hanelyp
Posts: 2230
Joined: Fri Oct 26, 2007 8:50 pm

Re: SpaceX News

Postby hanelyp » Tue Jun 05, 2018 3:46 am

ladajo wrote:Next up is a block V I think. I believe NASA wants SpaceX to launch 10 of them prior to authorizing manned certification.

Contrast with the SLS, "designed for manned flight", but unlikely to even have half that many launches, if it flies at all.
The daylight is uncomfortably bright for eyes so long in the dark.


Return to “News”

Who is online

Users browsing this forum: No registered users and 10 guests