Author Topic: Are the reusable systems modular?  (Read 2402 times)

Offline Pipcard

  • Full Member
  • ****
  • Posts: 471
  • Liked: 119
  • Likes Given: 97
Are the reusable systems modular?
« on: 10/18/2015 07:50 PM »
As in, can the landing legs (and other systems) be attached, relatively easily, to a first stage core that is normally expendable?

Or does the stage have to be specifically manufactured for reusability, in a somewhat separate production line?
« Last Edit: 10/18/2015 07:53 PM by Pipcard »

Offline DatUser14

  • Full Member
  • ****
  • Posts: 486
  • Liked: 112
  • Likes Given: 349
Re: Are the reusable systems modular?
« Reply #1 on: 10/18/2015 08:01 PM »
I think it has been shown that all stages are manufactured with the the leg attachment points, so yes I believe it is possible they could be interchangeable.
Titan IVB was a cool rocket

Offline cdleonard

  • Full Member
  • *
  • Posts: 112
  • Liked: 49
  • Likes Given: 75
Re: Are the reusable systems modular?
« Reply #2 on: 10/18/2015 09:15 PM »
As in, can the landing legs (and other systems) be attached, relatively easily, to a first stage core that is normally expendable?

Or does the stage have to be specifically manufactured for reusability, in a somewhat separate production line?

SpaceX skipped landing tests on the CRS-4 mission because they swapped the core with one originally intended for a GTO mission. The booster that eventually flew the ISS missing was missing leg attachment points. So in 2014 they were also manufacturing cores which couldn't have legs attached.

This might not be the case anymore. The F9 FT upgrades are intended to allow for first-stage recovery even on GTO missions.

Offline Jarnis

  • Full Member
  • ****
  • Posts: 1120
  • Liked: 568
  • Likes Given: 156
Re: Are the reusable systems modular?
« Reply #3 on: 11/01/2015 06:21 PM »
AFAIK all the upcoming cores have the reusability bits. Sure, legs and grid fins could be left off (they are bolted on at the launch site) if they somehow had a mission that required all the performance, but the rest is now "standard".

Offline Pipcard

  • Full Member
  • ****
  • Posts: 471
  • Liked: 119
  • Likes Given: 97
Re: Are the reusable systems modular?
« Reply #4 on: 12/04/2015 11:52 PM »
I'm also wondering about how much would these systems add to the dry mass of the F9 first stage. A couple tonnes, maybe?

Online Robotbeat

  • Senior Member
  • *****
  • Posts: 28047
  • Minnesota
  • Liked: 7860
  • Likes Given: 5232
Re: Are the reusable systems modular?
« Reply #5 on: 12/05/2015 01:17 AM »
As in, can the landing legs (and other systems) be attached, relatively easily, to a first stage core that is normally expendable?

Or does the stage have to be specifically manufactured for reusability, in a somewhat separate production line?
The stages are all manufactured to be compatible with reusability. Sometimes they're expended. Attachment points for the legs are on all the stages.

Legs are added at the launch site.

But yeah, the reusable stages and the expended stages are almost identical, just that one has the reusable equipment like legs and fins and the others don't.

It has been this way since the first v1.1 launch.
« Last Edit: 12/05/2015 01:17 AM by Robotbeat »
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

Offline dorkmo

  • Full Member
  • ****
  • Posts: 682
  • Liked: 308
  • Likes Given: 815
Re: Are the reusable systems modular?
« Reply #6 on: 12/05/2015 04:09 AM »
you could say the grid fins (and paraphernalia)  and the gas thrusters have to be specially built into the interstage. not sure different styles of interstage can just snap on and off?

another consideration is the gas storage for the pneumatic rams of the legs, i'd say that probably the biggest item that would be a chore to swap on and off.

Offline guckyfan

  • Senior Member
  • *****
  • Posts: 6650
  • Germany
  • Liked: 1721
  • Likes Given: 1665
Re: Are the reusable systems modular?
« Reply #7 on: 12/05/2015 07:20 AM »
you could say the grid fins (and paraphernalia)  and the gas thrusters have to be specially built into the interstage. not sure different styles of interstage can just snap on and off?

another consideration is the gas storage for the pneumatic rams of the legs, i'd say that probably the biggest item that would be a chore to swap on and off.

I think they would just leave the legs and grid fins including their actuators off. Maybe also sensors that are used only for landing. Other reuse components like the beefed up cold gas thrusters are likely not worth building a different stage or interstage both in weight and component value.

Offline cambrianera

  • Full Member
  • ****
  • Posts: 1426
  • Liked: 307
  • Likes Given: 249
Re: Are the reusable systems modular?
« Reply #8 on: 12/05/2015 06:42 PM »
As in, can the landing legs (and other systems) be attached, relatively easily, to a first stage core that is normally expendable?

Or does the stage have to be specifically manufactured for reusability, in a somewhat separate production line?
The stages are all manufactured to be compatible with reusability. Sometimes they're expended. Attachment points for the legs are on all the stages.

Legs are added at the launch site.

But yeah, the reusable stages and the expended stages are almost identical, just that one has the reusable equipment like legs and fins and the others don't.

It has been this way since the first v1.1 launch.

Maybe not all the cores:
http://forum.nasaspaceflight.com/index.php?topic=35853.msg1294078#msg1294078
Internal reinforcements for upper attachment point of legs were missing on CRS-4 core.
(CRS-4, not CRS-5)
« Last Edit: 12/05/2015 06:44 PM by cambrianera »
Oh to be young again. . .

Tags: