Author Topic: SpaceX Falcon Heavy Discussion (Thread 3)  (Read 191172 times)

Offline enzo

  • Full Member
  • *
  • Posts: 106
  • USA
  • Liked: 79
  • Likes Given: 607
Re: SpaceX Falcon Heavy Discussion (Thread 3)
« Reply #600 on: 12/30/2015 02:49 AM »
Want to bring this thread back for the new year, perhaps the year of FH.

Let's say there are a handful of landed stages by the time FH is ready to fly (likely), and at least one has been reflown successfully (maybe). Do you think recovered first stages can undergo whatever modifications necessary for use as side boosters (minor, as claimed)? If so, will FH demo flight use reflown boosters for cost savings?

One argument against is that part of developing FH is building at least one, including side boosters, from scratch. But that's irrelevant if they're nearly identical to first stages. Another is that perhaps reflight will have been shown, but not enough times to prove reliable for the high-profile FH demo.

Online Robotbeat

  • Senior Member
  • *****
  • Posts: 25725
  • Minnesota
  • Liked: 5818
  • Likes Given: 4324
Re: SpaceX Falcon Heavy Discussion (Thread 3)
« Reply #601 on: 12/30/2015 02:51 AM »
No. You'll save money by just using the recovered stages unaltered for more F9 flights. They've already started building the Falcon Heavy, and at this point they frankly can't afford a potential new problem to show up on this already-complicated vehicle.
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Online Lars-J

  • Senior Member
  • *****
  • Posts: 2693
  • California
  • Liked: 2122
  • Likes Given: 1211
Re: SpaceX Falcon Heavy Discussion (Thread 3)
« Reply #602 on: 12/30/2015 04:00 AM »
Want to bring this thread back for the new year, perhaps the year of FH.

Let's say there are a handful of landed stages by the time FH is ready to fly (likely), and at least one has been reflown successfully (maybe). Do you think recovered first stages can undergo whatever modifications necessary for use as side boosters (minor, as claimed)? If so, will FH demo flight use reflown boosters for cost savings?

One argument against is that part of developing FH is building at least one, including side boosters, from scratch. But that's irrelevant if they're nearly identical to first stages. Another is that perhaps reflight will have been shown, but not enough times to prove reliable for the high-profile FH demo.

It depends... According to a SpaceX'er on Reddit (seems legit), the octaweb for an FH side booster is slightly different from the current F9 octaweb. But what is not clear is if the F9's going forward after FH first flight will have that same octaweb configuration. So... Current F9's cannot be used as FH side boosters. But future F9's *may* be interchangeable with FH side boosters.

Offline sdsds

  • Senior Member
  • *****
  • Posts: 5471
  • "With peace and hope for all mankind."
  • Seattle
  • Liked: 573
  • Likes Given: 668
Re: SpaceX Falcon Heavy Discussion (Thread 3)
« Reply #603 on: 12/30/2015 04:12 AM »
Want to bring this thread back for the new year, perhaps the year of FH.

Whole-hearted agreement here! This should be they year of the Falcon Heavy!

[1] You'll save money by just using the recovered stages unaltered for more F9 flights.

[2] they frankly can't afford a potential new problem to show up on this already-complicated vehicle.

Again whole-hearted agreement on [2]: it sure seems like for the first few FH flights the rule to follow should be "keep it as simple as possible."

As for [1], I agree that if they can save money by reusing recovered and refurbished F9FT stages, they should definitely do so! But even if due to structural issues they can "only" reuse the Merlin engines, wouldn't that alone provide justification for the RTLS powered landing approach? (After all, that's essentially what ULA is claiming re: Vulcan....)
-- sdsds --

Offline macpacheco

  • Full Member
  • ****
  • Posts: 653
  • Vitoria-ES-Brazil
  • Liked: 272
  • Likes Given: 2073
Re: SpaceX Falcon Heavy Discussion (Thread 3)
« Reply #604 on: 12/30/2015 06:16 AM »
Methinks a new, fully reusable, methane fueled launcher powered by Raptors or Raptor variants will replace both F9 and FH. Larger payloads migrate to BFR.

Where does that leave the loads of progressively smaller satellites they would need to launch to make money?

Not a problem as long as Raptor based rockets are able to achieve full reuse in the order of 100x.
As long as expendables on the Eagle lite cost a few million, with 100 launches, even if Eagle lite costs 10x as a F9R, that would still be much cheaper than a F9R FT wasting the 2nd stage.
Doing bulk launches doesn't mean a fully loaded rocket is required. Customers would pay based on how much of a hurry they are in. As low as sub US$ 10 million if they could wait 6 months, or half the current F9R FT launch prices if they want to launch in a hurry. This would also incentive customers to build multiple birds and launch them together.
With a full reuse rocket, integrating the fairing and an upgraded dispenser ring might make sense.

The bread and butter of the launch market is still GTO and ISS destinations. GTO launches can be aggregated easily, can't them ? Plus perhaps hurried launches to GTO could be delivered directly to GEO or near GEO ? How much would that be worth in extra launch value ?
« Last Edit: 12/30/2015 06:33 AM by macpacheco »
Looking for companies doing great things for much more than money

Online guckyfan

  • Senior Member
  • *****
  • Posts: 5861
  • Germany
  • Liked: 1434
  • Likes Given: 1146
Re: SpaceX Falcon Heavy Discussion (Thread 3)
« Reply #605 on: 12/30/2015 07:27 AM »
The bread and butter of the launch market is still GTO and ISS destinations. GTO launches can be aggregated easily, can't them ? Plus perhaps hurried launches to GTO could be delivered directly to GEO or near GEO ? How much would that be worth in extra launch value ?

True for GTO as bread and butter. Going directly to GEO not so much. Doing it with Falcon Heavy leaves the upper stage stranded there, another big piece of space junk. Doing it with BFR would require a fully LEO refuelled vehicle for even a few com sats, so 4 or 5 launches including tankers. The delta-v for going to GEO and back with a heavy upper stage/MCT is huge, more than going to Mars and landing there.

Offline Ben the Space Brit

  • Senior Member
  • *****
  • Posts: 6779
  • A spaceflight fan
  • London, UK
  • Liked: 437
  • Likes Given: 488
Re: SpaceX Falcon Heavy Discussion (Thread 3)
« Reply #606 on: 12/30/2015 11:31 AM »
Something I've been puzzling over: Are there any differences, structurally, between the F9 v.1.2 core and the FH outboards? I'm wondering if one of the markets for reused cores might be to reduce FH production costs.
"Oops! I left the silly thing in reverse!" - Duck Dodgers

~*~*~*~

The Space Shuttle Program - 1981-2011

The time for words has passed; The time has come to put up or shut up!
DON'T PROPAGANDISE, FLY!!!

Online Jcc

  • Full Member
  • ****
  • Posts: 723
  • Liked: 153
  • Likes Given: 56
Re: SpaceX Falcon Heavy Discussion (Thread 3)
« Reply #607 on: 12/30/2015 11:39 AM »
Something I've been puzzling over: Are there any differences, structurally, between the F9 v.1.2 core and the FH outboards? I'm wondering if one of the markets for reused cores might be to reduce FH production costs.

Yes, the center core is structurally reinforced to bear more loading.


Tags: