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This is an outgrowth of the Falcon Heavy assembly thread, and is a logical direction for "inquiring minds wanting to know."
One of the first steps forward will be gaining certification for Air Force and NRO classified launches. The speculation on other industry related websites is up to 3 or 4 FH launches a year with classified payloads. Having this now "off the shelf" launcher available may pressure NASA into finally killing the incrementally moving SLS. At the current rate of SLS progress, it will be ready to launch just before the advancing glacier from the next ice age approaches Cape Canaveral.
http://spacenews.com/military-certifica … con-heavy/
Man rating, or Human rating, if you wish: I suspect there will be pressure for SpaceX to reconsider the statement attributed to Elon, where there will be no effort to have this vehicle certified for human flight operations. There were some rambling mumblings on the Everyday Astronaut about there being an extreme vibration problem, but I can find no evidence that is the case. I suspect that the Federal regulators are more of a problem than acoustic vibrations.
http://spacenews.com/spacex-no-longer-p … con-heavy/
Hoping that GW will chime in here with his usual insights and observations, as I never got to taking vibrations in as far as I progressed in Aerospace E.
It's my hope that at least a dozen central cores will be built before moving on to BFR, and all the Block 5 upgrades will be included therein.
I don't want to wait another 7 years to see the first BFR, but the enthusiasm of Musk overwhelms reality where timelines are concerned.
Last edited by Oldfart1939 (2018-02-09 19:10:31)
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The fact that SPACE X expected to lose the whole vehicle but in the end only lost the upper stage is incredibly impressive
of course the two boosters landing as they did was impressive
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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Long time no see Grypd its good to see you here. I thought so as well with the impression you get when seeing not 1 but 2 coming down to the landing.
As for the SLS its satelite use was only an after thought since nasa was to just use it for manned missions at first followed by some wanting to send probes to the outer planets faster....Sounds more like the new glenn might be a better fit for the military stuff but they are playing catchup....
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SpaceX has had a truly remarkable series of successes recently, and continues moving forward. Hopefully they don't overlook their advantage in heavy lift capability by pushing too many of their gifted engineers into the BFR project. There is a LOT of room for growth using the FH as it's basis; construction of a larger and more powerful second stage immediately comes to mind. In spite of Elon's recent comments about not pursuing a man rated version of the system, maybe a quick reality check will bring him to a somewhat different ultimate conclusion. The Moon in 3 years? Maybe it's possible through mods to some of the existing hardware. Certainly a lunar circumnavigation is feasible in that time frame.
As far as we know, vaporware has never completed a single mission. BFR is, at this juncture, mostly designs and (maybe?) some hardware.
Based on the 2011 start date of FH, and 2018 as first flight, we can only hope that BFR takes about the same amount of time--in spite of even more complex engineering problems. Maybe it will turn out to be only twice as hard as Musk thinks it will be and not an order of magnitude (more likely)?
Comment added in edit: SpaceX has a window of opportunity of about 2 years in which to capitalize on their advantage before the first SLS flight (if even by then!), and the first Blue Origin New Glenn launch. So--consider them to be at least 2 years ahead of the pack.
Last edited by Oldfart1939 (2018-02-11 14:11:26)
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Oldfart1939:
I've heard nothing about vibrations in the Heavy flight, although I haven't been looking for such, either. To the best of my knowledge, the worst vibration experiences are associated with the 5-segment SRB's stretched from the 4-segment shuttle design, and with the Saturn-V first stage decades ago.
The SRB oscillations are really a longitudinal-mode instability excited by bringing a barely-stable 4-segment design (some oscillation) into stronger resonance at the 5 segment length (very violent oscillation). At least, that's what it looked like to me. Shows up in both P and F traces vs time. Can significantly raise average burn rate and pressure from that expected. Very dangerous.
The old Saturn-V first stage oscillations I never heard an explanation for, that I understood. All I know is that they did "something" that quieted it down. It was never again a significant problem.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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GW-
Thanks for your observations. I suspect that one of the onlookers attributed Musk's decision to something that wasn't really the problem. They were coupled with some additional comments about acoustic effects. I watched the entire launch live from the SpaceX webcast, and subsequently an additional 4 or 5 times, but at no time did the webcasters ever make such a comment.
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If space x wanted to keep the falcon 9 going and still get to that next plateau then why not cluster 4 cores around the center to get even more payload to orbit with the current base design. This would allow for a longer second stage and more payload mass to orbit.
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SpaceNut-
That was another of the concept vehicles in the 2011 proposal, and referred to as the Falcon Super Heavy. But that would also require the ignition of 45 MerlinD-1 engines. I personally would argue for using a larger diameter central core vehicle, were that concept to be actualized.
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So how well would a new larger core with the Raptors and methane / lox wrapped with the Falcon 9 first stages work out for capabilities? Even a switched over design of a small raptor booster cores sounds interesting also with that newer central core...
Lots of possibilities....
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There have been a few Reddit posts recently that indicate SpaceX/Elon Musk seem to be considering an improved 2nd stage for FH, including a longer payload fairing and increased length of the entire vehicle. That would be the most effective means of upgrading the payload to orbit. Other comments seem to indicate the BFS passenger stage could be experimentally launched by FH.
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As you have meantioned it before changing out the engine and fuel type with this new design of the second stage would benefit Space X with its future BFR experience.
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SpaceNut-
It's one way of improving performance to LEO and correspondingly, obtaining some much needed data on performance of the new Raptor engine (vacuum version). Would certainly aid in the engine certification process.
Last edited by Oldfart1939 (2018-02-14 09:05:15)
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Wikipedia: Falcon Heavy
By 2008, SpaceX had been aiming for the first launch of Falcon 9 in 2009, while "Falcon 9 Heavy would be in a couple of years". Speaking at the 2008 Mars Society Conference, Musk also said that a hydrogen-fuelled upper stage would follow 2–3 years later (which would have been around 2013).
Everything is taking more years, but my question is "What about hydrogen"? Remember, Saturn 1 could lift 9 metric tonnes to LEO. They replaced the upper stage with the 3rd stage of Saturn V, producing Saturn 1B that could lift 20 metric tonnes to LEO. That's an incredible upgrade. Falcon rockets use a large first stage because it can be recovered, much smaller upper stage. So a hydrogen upper stage may not be as dramatic as Saturn 1B, but still. And since Elon spoke about it, what's happening with that?
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Robert-
So far I've seen nothing about a Hydrogen fueled upper stage. The Raptor is pretty well fixed with methylox propulsion, though. I'd be opposed to hydrolox on the basis of the extra tankage size involved.
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I don't know if I've asked this before. SpaceX has released pricing, with better explanation (in small print).
Capabilities & Services | SpaceX
Standard Payment Plan (2018 launch): Falcon 9: $62M (Up to 5.5 mT to GTO)
... Falcon Heavy: $90M (Up to 8.0 mT to GTO)
Performance (Performance represents max capability on fully expendable vehicle)
GTO: Falcon 9: 8,300 kg
... Falcon Heavy: 26,700 kg
This means "Standard Payment Plan" is with recovered core stages. Falcon 9 reduces capacity from 8.3 to 5.5 mT. Why does Falcon Heavy drop from 26.7 to 8.0 mT? Based on the ratio, I would expect 17.69 mT. Is this price for half capacity? That Falcon Heavy would launch 2 satellites at once?
The reason I ask is for a Moon mission. Would my Moon mission work? What is throw to TLI without fairing? My mission plan requires a Dragon capsule, converting the trunk into service module, and another stage. Difference between GTO and TLI are slight. Example: Proton K with Block D upper stage can throw 5,390 kg to TLI, or 6,300 kg to GTO.
Last edited by RobertDyck (2018-02-28 02:22:55)
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Robert-
My thoughts are the following: there are several options, and fully expendable is only one; a partially expendable version expends the central core but recovers the side boosters. Doing that conceivably allows a moon mission. Your trunk extension converted to a service module was in one of my earlier Mars mission architectures as well.
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It would be nice if they were working on this modification to the dragon as it opens up more use of it....
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Agreed!
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Just some more pipe-dreaming here: the standard payload fairing diameter is 5 meters on all these Falcon/Falcon heavy launches. SpaceX is now considering lengthening the fairing and also the overall length of the vehicles. If instead of a payload fairing and adapter, what's to stop them from enlarging and extending the Dragon trunk accordingly? An increase in second stage diameter would also be a worthy experiment. Based on the math, this would increase the volumes of said stages/vehicles by a factor of ~ 1.83, which with some extension of the trunk, and fitting it out as a service module, give a moon-capable vehicle in just a few years. The side-mounted Raptor engines on the Dragon 2 could serve as the maneuvering thrusters for entering lunar orbit. The Apollo 8 Redux is soon within the grasp of SpaceX!
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If we subsequently add in orbital assembly, we have many options for a lunar mission using Falcon Heavy. I don't have the deltaV for a lunar flyby and return available at my fingertips. An enlarged or modified cargo trunk, one converted to some basic living facilities and some propulsion capability would also work well, as Robert suggested earlier.
Last edited by Oldfart1939 (2018-03-01 19:53:00)
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