Author Topic: Can Falcon Heavy handle a larger fairing? (Read 40679 times)

envy887 · « **Reply #20 on:** 04/04/2017 05:23 pm »

What is the 330's expected diameter when stowed? I thought it was sized to launch on Atlas V 551, which would mean it's diameter should fit in SpaceX's 5.2m fairing diameter. Atlas doesn't offer a larger diameter fairing, just a longer one.

Kenp51d · « **Reply #21 on:** 04/04/2017 05:55 pm »

Quote from: envy887 on 04/04/2017 05:23 pm

What is the 330's expected diameter when stowed? I thought it was sized to launch on Atlas V 551, which would mean it's diameter should fit in SpaceX's 5.2m fairing diameter. Atlas doesn't offer a larger diameter fairing, just a longer one.

Also, what about length? Is the 330 short enough to fit?
Can the Falcon handle a longer fairing, seeing as the falcon is such a long skinny LV? My understanding is the LV's length width ratio (can't remember the term) is already near the limit. Don't know how that affects fairing length.

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dror · « **Reply #22 on:** 04/04/2017 06:36 pm »

I kind of remember reading, a long time ago, on FH page in the spacex site, that "other fairing sizes are possible, upon custommer demand" or some thing like that. To me, "other" meant bigger, but I could be wrong .
Any way, it's not there now

edkyle99 · « **Reply #23 on:** 04/04/2017 07:59 pm »

If SpaceX wants to compete for all of the EELV-Heavy class payloads, it will likely have to offer a longer Falcon Heavy fairing, at the very least - one that is comparable to the largest Delta 4 Heavy fairing.

- Ed Kyle

Asteroza · « **Reply #24 on:** 04/05/2017 03:13 am »

Considering the costs involved, would it behoove them to only design/build a larger diameter lengthened shroud that is cylindrical, or go whole hog with a long hammerhead type? Hell, would a hammerhead shroud potentially be easier to recover due to increased surface area and better shape for reentry?

Coastal Ron · « **Reply #25 on:** 04/05/2017 03:37 am »

Quote from: spacenut on 04/04/2017 03:37 am

From what I read it was 54 tons in reusable mode to LEO. It can't lift that to GTO or GSO. That is after the upgrade to Full Thrust recently. Two outer boosters would land back at the Cape, center core would land on the drone ship. I just think they will eventually need a larger fairing if they are to launch heavy LEO payloads for someone.

If you look at the SpaceX Capabilities & Pricing page for Falcon 9 and Falcon Heavy, they state performance for Falcon Heavy:

LEO = 64.0mT *
GTO = 22.0mT *
Payload to Mars = 4.02mT *

* Performance represents max capability on fully expendable vehicle

So you would have to pay more than $90M to get the full performance ability of Falcon Heavy, but it could put 54.4mT into LEO - likely assuming the standard fairing.

Edit: Per user jpo234 I have updated the LEO numbers to reflect the latest SpaceX update.

Zed_Noir · « **Reply #26 on:** 04/05/2017 09:19 am »

Quote from: envy887 on 04/04/2017 05:23 pm

What is the 330's expected diameter when stowed? I thought it was sized to launch on Atlas V 551, which would mean it's diameter should fit in SpaceX's 5.2m fairing diameter. Atlas doesn't offer a larger diameter fairing, just a longer one.

There was a 7.2 meter fairing offered by ULA in the Atlas V user guide. Of course the customer have to fund addition integration research for such a fairing.

SpaceX will have to field a larger fairing eventually to complete with the 7 meter fairing from Blue.

guckyfan · « **Reply #27 on:** 04/05/2017 09:33 am »

Quote from: Zed_Noir on 04/05/2017 09:19 am

SpaceX will have to field a larger fairing eventually to complete with the 7 meter fairing from Blue.

Or not. They may well wait until ITS or a derivate of it flies that has a lot more volume. They may have to design something like the Shuttle payload bay doors.

Ben the Space Brit · « **Reply #28 on:** 04/05/2017 09:55 am »

I'd be surprised if SpaceX hasn't addressed at least as a paper exercise a 7-7.5m PLF that extends down to the base of the interstage and can be offered to NASA or DOD in the event there is a payload large enough. However, right now at least, at most it would be a hypothetical model. There is no commercial impetus to go even into early-stage development.

jpo234 · « **Reply #29 on:** 04/05/2017 12:35 pm »

Quote from: Coastal Ron on 04/05/2017 03:37 am

If you look at the SpaceX Capabilities & Pricing page for Falcon 9 and Falcon Heavy, they state performance for Falcon Heavy:

LEO = 54.4mT *

Payload to LEO is now 64000kg.

spacenut · « **Reply #30 on:** 04/05/2017 01:09 pm »

That payload changes a lot. I still haven't really had my question answered. Yes I know there would be additional aerodynamic pressures. But, without extensive modification could the 2nd stage handle the weight and pressure of a larger fairing? And if there are rocket engineers here who can answer the question, what size would it be?

I know 99% of payloads can fit inside the existing fairing. However, with SLS coming on line at up to 8+ meters diameter, Vulcan in a few years with a 5+ meter diameter, and New Glenn with a 7m diameter, payloads can be larger in diameter, and possibly length also. Compared to those rockets, F9/FH is a small diameter rocket and possibly only a certain diameter and length size increase. Just wondering what size?

Also, F9/FH will be around for at least the next 10 years launching. It has incredible payload capabilities for the size rocket it is. If they weren't so against solids, removing the legs and using expendible mode I was wondering also if they could get FH payloads with say 4 solids attached to a F9 like Atlas V. That is getting off topic on my own thread. Back to a possible larger fairing.

DOCinCT · « **Reply #31 on:** 04/05/2017 08:51 pm »

Fairing sizes across launcher families can be tricky. For instance, on an Atlas 5, the fairing has to be long enough to enclose the centaur 2nd stage and the payload. A fairing on Falcon9/H doesn't have to do this but is constrained by the cylindrical space available (4.6mX6.7m) as opposed to the overall length (11m) which includes the cone shape at the top.
In addition, you have to factor in the capabilities of the PAF which limits weight (10,886 kg / 24,000 lb) as opposed to volume/size.
Note: The Bigelow B330 is 13.7 m (44.9 ft) in length and fits into a 5m fairing and weighs at least 20,000 kg (43,000 lb)

smfarmer11 · « **Reply #32 on:** 04/05/2017 08:58 pm »

If youre already going to the length of having a new payload fairing designed, having a custom or heavier payload adapter wouldn't be that great of a problem.

Nomadd · « **Reply #33 on:** 04/05/2017 09:11 pm »

Falcon 9 User's guide

Pipcard · « **Reply #34 on:** 04/06/2017 12:32 am »

Quote from: Jim on 04/04/2017 02:37 pm

Quote from: John Alan on 04/04/2017 06:13 am

The cost and time needed to move it around is the lowest in the world... IMHO...
70 MPH cross country with a handful of people... Makes everyone else look silly in comparison...
Any bigger diameter... and it will add millions to the logistical expenses...

Unsupported statements. It would not add millions and it does not make others silly

Quote from: abaddon on 04/04/2017 02:45 pm

Seriously, water transport is a little slow but it is not particularly expensive. Can we please not indulge in breathless hyperbole about everything SpaceX does?

Is there any analysis of the actual costs?

Arcas · « **Reply #35 on:** 04/06/2017 12:42 am »

I doubt they would invest in new fairing technology before the new upper stage gets going.

JamesH65 · « **Reply #36 on:** 04/06/2017 11:04 am »

Quote from: Arcas on 04/06/2017 12:42 am

I doubt they would invest in new fairing technology before the new upper stage gets going.

As far as is known, there is NO new upper stage. For some reason people thing that there is, but there appears to be no evidence for it whatsoever.

spacenut · « **Reply #37 on:** 04/06/2017 12:23 pm »

The only evidence of a new upper stage is the Air Force contract to develop an upper stage Raptor engine. For what the Air Force wants, who knows. Guys have suggested a 5.2m upper stage with a Raptor upper engine, the same length of the existing upper stage. A new fairing would have to be made and could be made longer. However, this upper stage is NOT in the development stage, only the engine.

Now, the Bigelow 330 module at 13.7m long and 20 tons would not fit in the existing fairing. Weight wise, it is ok, even for a F9 expendible, but the existing fairing is only 11.4m internally. Maybe all they would need is a fairing stretch.

However, if they had a fairing large enough, with the new figures for FH expendable, a 330 module may could be launched to cis-lunar space for the station NASA is contemplating. A few of these, some solar panels, some extra docking ports, and you have a lunar station. All FH could do without SLS.

To me with FH soon to come on line, a larger fairing would be needed to competed for payloads that SLS or even New Glen could launch. Seems like the capability of the rocket is there, just the fairing is undersized for larger payloads that FH could launch.

Kaputnik · « **Reply #38 on:** 04/06/2017 12:27 pm »

Quote from: edkyle99 on 04/04/2017 05:21 pm

Quote from: spacenut on 04/04/2017 03:56 pm
Yes, I just want to know if the second stage as is, can handle a larger fairing. Wider and maybe a little longer for some larger future potential payloads like a 330 module. I know one of the Atlas V fairings encompasses the entire second stage. Just wondering if a 6m fairing say a little longer.
We can look at Titan 4 for an example of what has been done. Titan 4 carried a 200 in diameter fairing up to 1,067 inches long atop a 120 inch diameter core second stage. A 144 inch diameter Falcon 9 second stage might be expected to handle a fairing up to 240 inches (6.096 meters) diameter if the same relative diameter change were possible.

This does not answer whether the current Falcon 9 stage can structurally handle such a fairing. My guess would be that some changes would be needed, and of course the entire configuration would have to be qualified (wind tunnels, separation tests, etc.).

- Ed Kyle

I would hazard a guess that F9, being already very much at the high end of fineness ratio, is more susceptible to bending loads than other vehicles. So possibly less scope for increasing the fairing size.

yg1968 · « **Reply #39 on:** 04/06/2017 12:48 pm »

There was plans for a taller fairing at some point but they seemed to have been dropped. See below:

Quote from: yg1968 on 05/02/2014 11:12 am

Quote from: Lars_J on 05/02/2014 05:00 am

Quote from: yg1968 on 05/02/2014 03:36 am
Quote from: manboy on 05/02/2014 03:27 am
The BA-330 is only 19,500 kg so it doesn't need a crossfed Falcon Heavy.

The BA-330 needs a taller fairing than the one that will be used by initial version of the FH (which will be the same fairing as the F9). The upgaded FH will have a fairing that is 15' taller. But the upgraded FH will only be ready in 2017.

I must have missed the news about a bigger FH fairing option. When was that revealed?

The information is from the Bigelow Gate 2 report (the charts in the report are dated August 1 2013). According to the report, there is two versions of the FH: the regular version (first launch expected in 2015) and the upgraded version (the first launch of the upgraded version is expected to be in 2017). The regular version of the FH uses the same fairing as the F9. The upgraded FH uses the 15' taller fairing.

I beleive this is why there is two prices for the FH on SpaceX's website: one for less than 6.4 tons to GTO and one for more than 6.4 tons to GTO.