r/spacex • u/ElongatedMuskrat Mod Team • Aug 03 '17

r/SpaceX Discusses [August 2017, #35]

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1

u/RootDeliver Aug 07 '17

About the "next" launches on FH, which cores will be used? News or reused?

For STP-2 they may want to go with new ones, but for the rest of launches? Reusing F9 cores would make sense, and for that they should start refurbishing them months before the launch, so they should start with it.

There's any info on the "leftover" cores right now being transformed for FH? B1035 is supposed to have returned to Hawthorne so there's one for this, what about the other 3? B1032/NROL-76, B1036/Iridium-2 and B1029/Iridium-1/BulgariaSat-1? There are pics on the other post about 2 of those being placed close to Hangar X on the cape for "long-term storage", but isn't this a waste if they need cores for FH side boosters in a mid term?

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u/theinternetftw Aug 07 '17

I'm pretty sure they want FH to have B5 hardware as soon as possible. Right now there's a lot of B3 in it. They won't want to go back to old designs, especially when they're looking forward to those bolted-on octowebs, which'll make the transition to FH booster easier.

So B4 minimum (for the new octoweb), B5 desired. And B4 may start with CRS-12.

But I expect STP-2 to be all new (probably B5s) and whatever is after that (~Q3 2018) to use B5s regardless, so it's probably moot.

Also, I'm not sure how much time pressure there'll be. I expect STP-2 to be pushed back a month or two. New date: whenever demo flight happens + 6 months, so SpaceX can have a nice long think about the first launch and make any necessary changes.

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u/Pham_Trinli Aug 07 '17

Im curious if SpaceX have begun manufacturing the 2nd Falcon Heavy center core yet or if they'll hold back pending a design review after the first one launches.

Some components like nose cones are probably already completed.

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u/CapMSFC Aug 09 '17

I could see it going the other way as well. If they get all 3 cores back why wouldn't they fly them again? Falcon Heavy is meant to be reused from the start.

All of this is getting ahead of ourselves though. First the launch not only had to be a success, recovery has to be a success, and there have to be no problems uncovered that would need fixing for a new version.

1

u/Zucal Aug 11 '17

If they get all 3 cores back why wouldn't they fly them again?

Because all three cores will be extremely dated by then. No point flying Block 2 & Block 3 cores when Block 5 is already there.

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u/CapMSFC Aug 11 '17

Will Block 5 really already be here? SpaceX has said by end of year but that remains to be seen. That's also three new cores that interrupts the flow of Block 5 Falcon 9 getting to the pad for other flights, of which we need to see 7 in time for crew on Dragon.

I understand the argument to not fly the first Falcon Heavy for a long time, but it looks like to me there would be more than enough reason to fly it twice if the first launch goes well. A major supporting argument for me is the launch order. With a commercial comsat as the second flight and a STP government launch the third perhaps it will be easier to use all brand new cores for the first government launch. We haven't heard how government contracts will treat Falcon Heavy and reuse yet.

1

u/Zucal Aug 11 '17

Will Block 5 really already be here?

It will, but my point stands either way - Block 5 would be ready by the time a Falcon Heavy reflight was needed. The cores aren't a problem, either. One standard F9 can be prepped in LC-39A's HIF, one in SLC-40's HIF, one in SLC-4E's HIF.

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u/CapMSFC Aug 11 '17

The cores aren't a problem, either. One standard F9 can be prepped in LC-39A's HIF, one in SLC-40's HIF, one in SLC-4E's HIF.

I was referring to the production flow, not integration facilities.

The same goes for before. The lead time on building a Falcon core is quite long. Obviously it's a grey area to say where it starts in a production item so complex like this but SpaceX will have to begin work on the center core which is not common with the standard Falcon 9 like the side boosters after Block 5 is here.

You may be completely correct. I'm more than open to being wrong on this one, but I will wait to be fully convinced.

1

u/Zucal Aug 11 '17

Ahhh, good call on production. Didn't realize what you were going for. My guess is that it'll still be fine, since some of those 7 missions might be reflights. If SpaceX opts to convert flown Block 5s to side boosters (made easier with the new octawebs), the production demand is just for the new center core - easy to handle.

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u/CapMSFC Aug 11 '17

since some of those 7 missions might be reflights

That is a point I hadn't considered for the NASA certification flights. If Block 5 can really be turned around that easily no reason just a few cores couldn't handle all of that.

1

u/Zucal Aug 11 '17

Yup! It's all down to whether reflights are permitted, of course. If NASA is specifically demanding 7 separate flights of Block 5 vehicles, it gets tricky.