Quote from: Proponent on 04/06/2011 03:05 pmQuote from: Joris on 04/06/2011 02:58 pmQuote from: Proponent on 04/06/2011 02:44 pmWhat existing ultra-heavy payloads? The only payloads I'm aware of that would require the Falcon Heavy's capabilities are Bigelow modules larger than the BA-330 -- which hasn't flown yet -- and NASA HSF payloads. None of these really qualifies as "existing." To quote from the press conference,Anything that currently flies on a rocket more than $100m is a customer.Atlas V 5xx, Proton, Ariane5 are all in the same price-class. I wouldn't have thought that payloads which can be flown on existing vehicles qualify as "ultra-heavy," although only FinalFrontier can say definitively what he meant. Falcon Heavy may attract payloads from existing vehicles and fly them without using its full capability or it might fly multiple payloads at once. That's different from lofting payloads heaver than those which existing vehicles can carry.When a rocket has lots of capacity to spare people always find a way to use it. They can just double or triple up on the number of standard sized satellites launched at once. This is nothing new- look at Ariane 5 when it came out with more than twice the standard com sat capacity.This argument is not new. If you look at the trends you will see that com sat size behaves like a gas over long enough time scales. They grow to fill the capacity available, or more exactly they grow to fill out a specific capacity per dollar range. Evan Ariane 5 is having this problem, the only coms sats able to double up on it now are on the smaller end of the com sat size range these days. This is why the Europeans have either recently upgraded or are working on capacity upgrades for the Ariane 5.The FH performing as advertised, or even if the true cost numbers are significantly more (double to tripple) than advertised, is well within that sweet capacity per dollar range that encourages growth in com sat size.
Quote from: Joris on 04/06/2011 02:58 pmQuote from: Proponent on 04/06/2011 02:44 pmWhat existing ultra-heavy payloads? The only payloads I'm aware of that would require the Falcon Heavy's capabilities are Bigelow modules larger than the BA-330 -- which hasn't flown yet -- and NASA HSF payloads. None of these really qualifies as "existing." To quote from the press conference,Anything that currently flies on a rocket more than $100m is a customer.Atlas V 5xx, Proton, Ariane5 are all in the same price-class. I wouldn't have thought that payloads which can be flown on existing vehicles qualify as "ultra-heavy," although only FinalFrontier can say definitively what he meant. Falcon Heavy may attract payloads from existing vehicles and fly them without using its full capability or it might fly multiple payloads at once. That's different from lofting payloads heaver than those which existing vehicles can carry.
Quote from: Proponent on 04/06/2011 02:44 pmWhat existing ultra-heavy payloads? The only payloads I'm aware of that would require the Falcon Heavy's capabilities are Bigelow modules larger than the BA-330 -- which hasn't flown yet -- and NASA HSF payloads. None of these really qualifies as "existing." To quote from the press conference,Anything that currently flies on a rocket more than $100m is a customer.Atlas V 5xx, Proton, Ariane5 are all in the same price-class.
What existing ultra-heavy payloads? The only payloads I'm aware of that would require the Falcon Heavy's capabilities are Bigelow modules larger than the BA-330 -- which hasn't flown yet -- and NASA HSF payloads. None of these really qualifies as "existing." To quote from the press conference,
When a 53 ton launcher is cheaper than a 20 ton launcher, people will buy the first one to launch their 20 ton payload.There's no need for ultra-heavy payloads to justify Falcon Heavy.
Quote from: Joris on 04/06/2011 03:29 pmWhen a 53 ton launcher is cheaper than a 20 ton launcher, people will buy the first one to launch their 20 ton payload.There's no need for ultra-heavy payloads to justify Falcon Heavy.I suspect this is exactly what will happen. All of the FH's payloads will not be classifiable as "heavy" payloads for some time to come. Most of them will be re-manifested from existing LV's. Like he said: 1/3 the price. So what if FH's capacity isn't fully utilized at first? He'll gain flight history by flying it as often as he can, even if it's only with a couple of 15 ton payloads at a time.You just wait until somebody that had planned to fly on the Atlas or Delta pulls their MOU and manifests on the FH! THAT'S when the ULA execs *might* get their head out of their backsides and smell the coffee on the tray that is rapidly being wheeled away from them!While the FH's capacity is being under-used and the HLV is gaining a track record, REAL heavy payloads will begin to show up. It will just take time for that to happen because nobody's got one yet, because there hasn't been a HLV to fly them on. Not so (soon) anymore.
Satellites might grow to make fuller use of FH's capability, but that doesn't address the question of what "existing" ultra-heavy payloads there are.
According to http://www.spacex.com/Falcon9UsersGuide_2009.pdf (page 10) F9 block II uses Merlin 1C at 1,125,000 lbf (sea level), probably what MP99 is calling the Merlin 1C+. This seems to be the basis of the 10,450 kg from http://www.spacex.com/falcon9.php
Presumably at some time they had planned to upgrade to using Merlin 1D at 1,250,000 lbf
now Merlin 1D has come in at 1,400,000 lbf.
Well, if Falcon Heavy performes anywhere near what is advertised (53mT to LEO, or even 45mT to LEO), then that means that the proposed Falcon X is redundant. There is no longer any justification for it that I can see.One can also ask if there is even any interest in developping the Merlin-2, since having a cluster of such high-performing Merlin-1Ds would guarantee engine-out capability.The most logical further upgrade to FH would be the FHR with a Raptor upper-stage and maybe a larger fairing. Such a rocket would be in the 50-60mT to LEO range, depending on true Merlin 1D and cross-feed performance.The next step after that could indeed be a FXX-type... Although that could concievably also be a first-stage F9 cluster with a new upper stage rather than a monolithic rocket (it would require a Merlin 2, though, because otherwise the number of 1st stage engines would be horrific).
Why would the Falcon X be redundant?
Either way, you'd have two LV cores you are making. But with FX rather than FXX, you have more flexibility, and would likely do a lot more FX cores per year than you would FXX cores.
Quote from: Lobo on 04/06/2011 04:41 pmWhy would the Falcon X be redundant?Its payload range is covered by Falcon HeavyQuoteEither way, you'd have two LV cores you are making. But with FX rather than FXX, you have more flexibility, and would likely do a lot more FX cores per year than you would FXX cores. Might as wel make a Falcon XX, since you are not going to use Falcon X if you got Falcon Heavy. Developing a Falcon super heavy with 5 Falcon 9 cores might be the easiest.Anyways, Falcon X and XX are in noway final.
Quote from: Proponent on 04/06/2011 03:42 pmSatellites might grow to make fuller use of FH's capability, but that doesn't address the question of what "existing" ultra-heavy payloads there are.Right now there aren't any. But that doesn't mean that the FH's capacity won't be utilized. See my post above. It's just cheaper to fly on the FH, so re-manifesting *will* happen. There are some potential payloads that are not so far along in their designs that thay can't be altered to be heavier in order to loosen the constraints imposed on them by the existing capacities of either mass or PLF size. I speculate that we'll actually see a couple of those before we see one that was designed from the beginning for the new capability.Just don't make the mistake of thinking that FH won't fly because there are no heavy payloads yet. At $1,000 a pound to LEO who cares if there's still room left for more onboard when it launches? Seriously. At 1/3 the price - who cares?
The problem with F9SH is volume. You get mass to LEO that might approach 70mt range, but you are putting a PLF on that narrow F9 core. I think you'll run out of PLF size before you max out your mass.
Can FH put a payload on GEO? Because even Ariane 5 only goes to GTO. A payload that expected to be put in GTO put in GEO has 5 to 7 years more fuel. So that's other way to use the extra capacity. What I'm not sure is if it actually can put them into GEO.
Quote from: baldusi on 04/06/2011 07:13 pmCan FH put a payload on GEO? Because even Ariane 5 only goes to GTO. A payload that expected to be put in GTO put in GEO has 5 to 7 years more fuel. So that's other way to use the extra capacity. What I'm not sure is if it actually can put them into GEO.It can, but the resulting payload is less than an Atlas V.
Quote from: Downix on 04/06/2011 07:15 pmQuote from: baldusi on 04/06/2011 07:13 pmCan FH put a payload on GEO? Because even Ariane 5 only goes to GTO. A payload that expected to be put in GTO put in GEO has 5 to 7 years more fuel. So that's other way to use the extra capacity. What I'm not sure is if it actually can put them into GEO.It can, but the resulting payload is less than an Atlas V.Falcon Heavy can make a 30klb TMI. Atlas V 551 launches less than 20klb to GTO. How is this less?
TMI is not GTO. Also, the 551 is not the highest end Atlas either, the 552* is. And in addition, Atlas's higher isp engine with more restart capacity means that low-energy transfer maneuvers are now an option while the F9 with it's weaker isp and limited restart capacity just cannot match.
Quote from: Downix on 04/06/2011 08:16 pmTMI is not GTO. Also, the 551 is not the highest end Atlas either, the 552* is. And in addition, Atlas's higher isp engine with more restart capacity means that low-energy transfer maneuvers are now an option while the F9 with it's weaker isp and limited restart capacity just cannot match.TMI requires more DeltaV than GTO.Its 2.5km/s for GTO versus 3.8km/s for TMIIf you can launch 15tons to TMI, you could launch more to GTO.Atlas V Heavy cannot even launch 15 tons to GTO. Let alone more than that to TMI.