Author Topic: Reusable First Stages and Boosters  (Read 8282 times)

Offline Kaputnik

  • Extreme Veteran
  • Senior Member
  • *****
  • Posts: 2830
  • Liked: 471
  • Likes Given: 442
Reusable First Stages and Boosters
« on: 07/24/2006 07:36 PM »
Hello all, what a fascinating forum this is! Since there are clearly some very well informed people here perhaps somebody can answer a simple question for me? It hardly seems right putting it in 'advanced concepts' but since it's never really been done AFAIK this is where it belongs.
Reusable first stages/strap-ons have been mooted many times, and the validity of the concept seem to be taken as a given by SpaceX and the like; they were proposed for the Energia/Zenit system and have (sort of) been used for STS. They also seem, to me, to make a lot of sense. With the simple addition of a parachute and an airbag you can save yourself the hassle of constructing an entirely new rocket stage- and first stages are of course the biggest parts of a rocket.
As I am aware, the closest we have got to this is with the STS SRBs, which by all accounts are barely worth the costs of recovery and refurbishment. The Ariane boosters are similarly recovered but are only studied and not reused. I could understand how solid propellant stages, which presumably must be dissasembled for refuelling, do not lend themselves well to economical reuse. On the other hand, it seems to make perfect sense to reuse liquid fuelled boosters and first stages- even if there was damage to the tank structure the engines would be worth recovering.
The Zenit 1st stage was designed as a strap-on booster for Energia, and as such was to use parachute and airbag recovery. It was designed to last for ten flights and in tests the engine has been capable of twice that number of firings. Why, then, is nobody recovering the Zenit 1st stage? I cannot understand this and the usual political job creation arguments don't work because Zenit is operated on a completely commercial basis. SeaLaunch even have the necessary infrastructure for sea recovery- so there must be a very good reason.
Any suggestions? And do you think SpaceX can succeed where other have failed (or not even tried?)
Waiting for joy and raptor

Online Chris Bergin

RE: Reusable First Stages and Boosters
« Reply #1 on: 07/24/2006 11:01 PM »
Welcome to the site (bit surprised no one has answered this yet!) Although I know there's some good references to the Soviet hardware on the Buran threads.

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 32340
  • Cape Canaveral Spaceport
  • Liked: 10994
  • Likes Given: 327
Re: Reusable First Stages and Boosters
« Reply #2 on: 07/25/2006 12:01 AM »
saltwater intrusion is the reason.

Sealaunch doesn't have the cranes or the deck space for retrieval

Offline Kaputnik

  • Extreme Veteran
  • Senior Member
  • *****
  • Posts: 2830
  • Liked: 471
  • Likes Given: 442
Re: Reusable First Stages and Boosters
« Reply #3 on: 07/25/2006 10:12 AM »
Quote
Jim - 25/7/2006  12:48 AM

saltwater intrusion is the reason.

Sealaunch doesn't have the cranes or the deck space for retrieval

Perhaps my original post came across as too specific. I wouldn't expect Sealaunch to be able to recover booster without some sort of modfication to their fleet (that would have been even harder to understand), but I was using it as an example of where a company is not bound by political pressures and is already operating a similar infrastructure to what would be required, i.e. large deep sea vessels.
Is saltwater intrusion really such a serious problem that it couldn't be prevented quite easily? How much damage is done to an engine when in contact with saltwater for a few hours? It seems hard to imagine that a nozzle and combustion chamber built to survive extreme pressures and temperatures is less water resistant than a wristwatch. Even if the chamber/nozzle are written off the turbopumps at least be sealed against the water. I would have thought that aft-mounted flotation devices could keep the engines clear of the water quite easily.

In any case Zenit (and other LV) first stages are crashing on land downrange from Baikonaur all the time. From what I've read there is a thriving industry in recycling wrecked components which are scavenged by locals and sold to scrap dealers- not a nice business when some of the wreckage is from Proton stages. Nasty hypergolic stages aside, you would think it would make more sense to try and keep them (or just the engines) intact for reuse.

Note that I am working here on the assumption that there are very good reasons for non-reuse of liquid-fuelled first stages. They just escape lay people like me. It also makes me worry about mr Musk and his plans for keeping costs down.
Waiting for joy and raptor

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 32340
  • Cape Canaveral Spaceport
  • Liked: 10994
  • Likes Given: 327
Re: Reusable First Stages and Boosters
« Reply #4 on: 07/25/2006 11:57 AM »
KISS is the reason.  Recovery systems add weigh and complexity.  A recoverable stage is not an expendable stage with recovery hardware.  Margins have to be increased.  Landing may cause different load path, requiring beefed up structure.  The inspection and refurb are manpower intensive meaning $.

Offline TyMoore

  • Veteran
  • Full Member
  • ****
  • Posts: 482
  • Eureka, CA, USA
  • Liked: 2
  • Likes Given: 1
Re: Reusable First Stages and Boosters
« Reply #5 on: 07/25/2006 02:24 PM »
I wonder about the possibility of looking at upperstage hardware as part of delivered payload.  Conceivably a spacecraft upper stage could be designed with dissasembly in mind, so it should be possible, atleast in principle, to think of a spent upper stage as part of the 'delivered' cargo to a space station. A purpose designed cryogenic upper stage, or perhaps something like a modified space shuttle E.T. could supply substantial materials that could be used to expand a space station. A very large and useful space hanger could be constructed from the liquid hydrogen section of a space shuttle E.T., as well as spaces able to support pressures suitable for shirt sleeve environments. I would imagine that the inside of the tanks don't possess any coatings or chemicals incompatible with a breathable atmosphere later on (once flammable hydrogen was vented away by opening the tank to space for a bit.)

At the very least, additional radiation shielding could be had simply by carving up the tank barrel sections into long thin plates, and attach them to the outside of living areas. Granted reboost propellant consumption would increase, but a suitable application of electrodynamic tethers ought to offset that.

Orbital reuse of spent stages and spent ET's have been proposed before in quite a few forms. A change of philosophy about spent upperstages as part of a secondary but useful cargo/material resource may be helpful...

Offline kevin-rf

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8650
  • Overlooking the path Mary's little Lamb took..
  • Liked: 1120
  • Likes Given: 243
Re: Reusable First Stages and Boosters
« Reply #6 on: 07/25/2006 02:50 PM »
On one of the early Atlas V flights didn't they make an attept to recover one of the Atlas V Solid Rocket Boosters theorizing it might actually survive the fall in one peice?

Never heard the outcome on it ... Did they get an intact spent booster back?
If you're happy and you know it,
It's your med's!

Offline hop

  • Senior Member
  • *****
  • Posts: 3311
  • Liked: 449
  • Likes Given: 801
Re: Reusable First Stages and Boosters
« Reply #7 on: 07/25/2006 08:54 PM »
Quote
kevin-rf - 25/7/2006  7:37 AM

On one of the early Atlas V flights didn't they make an attept to recover one of the Atlas V Solid Rocket Boosters theorizing it might actually survive the fall in one peice?

Never heard the outcome on it ... Did they get an intact spent booster back?
These pictures show that  ith no recovery system at all, soyuz strapons land pretty intact. Solids will tend to be denser, they but they will also tend to be stronger.

Given the how intact these things land, it shouldn't take that much work to recover the engine at least*. The fact that this isn't done is probably a good indication that refurbishing is nearly as costly as just building a new one. (I'm aware that those particular engines aren't designed to be re-used.)

*my thought for recovering just the engines is that you could use the tanks as a crush shock absorber. You need a drag device to make sure you fall tank first, and some airbags around the engine to protect it on impact. By doing this you should reduce the mass of your recovery system quite a bit.

Offline zinfab

  • Space Junkie
  • Full Member
  • ***
  • Posts: 372
  • North Carolina
  • Liked: 0
  • Likes Given: 0
RE: Reusable First Stages and Boosters
« Reply #8 on: 07/26/2006 03:01 AM »
Ty, your idea is quite popular. I can't find the link in these forums, but one member posted a cool site that repurposed ETs for all sorts of things. In fact a quick google search didn't turn it up, but turned up lots of graduate student projects:

http://www.google.com/search?hl=en&q=external+tank+living+environment&btnG=Google+Search

Offline TyMoore

  • Veteran
  • Full Member
  • ****
  • Posts: 482
  • Eureka, CA, USA
  • Liked: 2
  • Likes Given: 1
RE: Reusable First Stages and Boosters
« Reply #9 on: 07/26/2006 03:55 AM »
Thanks for the links--I've studied a lot of them. The main problem with reusing the ET's is contending with the polyurethane foam on the surface of the tank. This would be a real problem if one wanted to use the tank materials for something other than as a structure all by istelf: if one wanted to section the tank, or cut it into strips for other structural purposes would entail a lot of post processing to remove excess foam--a tough, dirty and time consuming job on the ground let alone in orbit!


Thanks hop for the link to the boosters in Kazahkstan--that must be something else to see those things fall out of the sky! The engines were remarkably intact--I just wouldn't want to ride a ship with those particular rockets in the tail! Recycling space hardware makes sense if the money saved is greater than the economics of building new hardware--and I don't see this happening unless the volume of launches is really high, or the launch vehicles are really big, or both.

What I do think makes sense is adopting a maximum payload philosophy--what I mean by this is this:

If a launch vehicle can deliver say 15,000 kg to a LEO space station, and if it is only carrying 3,000 kg, with a 6,000 kg transfer vehicle, then what if we were to sort of keep an additional 6,000 kg of propellant residuals? This is a gross over simplification--granted--but simply thinking in terms of  delivering spent upper stage structure and propellant residuals, in addition to the payload to a LEO Depot starts to make more sense. Propellant residuals in an ET can be as much 15,000 kg--this would be a substantial value if delivered to a space station cryogenic propellant/material depot.

Thinking in these terms could allow for substantial propellant savings for reboosting,  increased safety margins for additional radiation shielding, and increase usable material through put and simultaneously reduce  supply costs...

Offline Kaputnik

  • Extreme Veteran
  • Senior Member
  • *****
  • Posts: 2830
  • Liked: 471
  • Likes Given: 442
Re: Reusable First Stages and Boosters
« Reply #10 on: 07/28/2006 02:03 PM »
Those photos from Kazahkstan are pretty cool. I'm amazed by just how intact the Soyuz boosters are when presumably they landed tail-first at several hundred mph, clearly the structure is quite robust. Which is more than can be said for those poor cows.
The Soyuz was of course designed as an ICBM... not much call for refurbishment if you're starting WWIII. The same is true for many LVs and I wonder if the expendable mentality has simply never moved on?
If one of those boosters came down in my garden (and didn't land on my house) I'd be very tempted to see whether it could be made to fly again... well it's better than an Estes anyway...
Waiting for joy and raptor

Offline mlorrey

  • Member
  • Senior Member
  • *****
  • Posts: 2133
  • International Spaceflight Museum
  • Grantham, NH
  • Liked: 10
  • Likes Given: 0
Re: Reusable First Stages and Boosters
« Reply #11 on: 07/28/2006 09:55 PM »
Geez, how many people get pancaked by these falling boosters?
VP of International Spaceflight Museum - http://ismuseum.org
Founder, Lorrey Aerospace, B&T Holdings, ACE Exchange, and Hypersonic Systems. Currently I am a venture recruiter for Family Office Venture Capital.

Offline publiusr

  • Elite Veteran
  • Full Member
  • ****
  • Posts: 1540
  • Liked: 1
  • Likes Given: 2
Re: Reusable First Stages and Boosters
« Reply #12 on: 10/17/2006 10:41 PM »
I don't know--how many get killed in winged airplanes? Save the headaches of winged boosters. Go ballistic.

Offline tnphysics

  • Regular
  • Full Member
  • ****
  • Posts: 1073
  • Liked: 0
  • Likes Given: 0
Re: Reusable First Stages and Boosters
« Reply #13 on: 09/12/2007 12:03 AM »
I like the idea of reusing rockets.

Offline BarryKirk

  • Member
  • Full Member
  • **
  • Posts: 260
  • Liked: 1
  • Likes Given: 0
RE: Reusable First Stages and Boosters
« Reply #14 on: 09/13/2007 05:23 PM »
OK here is an idea that is totally off the wall and out of the box.  Please shoot this one down...

The idea is that the most expensive part of the booster are the engines and avionics.

1) After US seperation, allow the tank to seperate from the engines and avionics package.  However, keep the 2 connected with a tether.  Say 200' tether.

2) Would it be possible with the proper design and maybe use of explosive bolts to reconfigure the tank to something that has a lot of drag?  Their is a lot of thin walled metal in the tank.  I'm not talking about the same kind of drag as a parachute, but more than just an empty tank.  Enough to slow down the descent.

3) It should be possible to have an aircraft loitering around in the area where the booster is coming down.

4) Have a specially designed aircraft snag the engine and avionics package and carry it back to base.


Offline meiza

  • Expert
  • Senior Member
  • *****
  • Posts: 3068
  • Where Be Dragons
  • Liked: 3
  • Likes Given: 3
Re: Reusable First Stages and Boosters
« Reply #15 on: 09/13/2007 05:40 PM »
Heh, split the tanks in half or more longitudinally and point the concave sides down. You might be able to do a helicopter with lift in the crude circle section profile wings. :)

Offline Kaputnik

  • Extreme Veteran
  • Senior Member
  • *****
  • Posts: 2830
  • Liked: 471
  • Likes Given: 442
RE: Reusable First Stages and Boosters
« Reply #16 on: 09/13/2007 07:38 PM »
Quote
BarryKirk - 13/9/2007  6:23 PM

OK here is an idea that is totally off the wall and out of the box.  Please shoot this one down...

The idea is that the most expensive part of the booster are the engines and avionics.

1) After US seperation, allow the tank to seperate from the engines and avionics package.  However, keep the 2 connected with a tether.  Say 200' tether.

2) Would it be possible with the proper design and maybe use of explosive bolts to reconfigure the tank to something that has a lot of drag?  Their is a lot of thin walled metal in the tank.  I'm not talking about the same kind of drag as a parachute, but more than just an empty tank.  Enough to slow down the descent.

3) It should be possible to have an aircraft loitering around in the area where the booster is coming down.

4) Have a specially designed aircraft snag the engine and avionics package and carry it back to base.


I have no doubt that it could be made to work... I also have no doubt that it would be hugely complicated and expensive!

One idea I've toyed with recently is that rather than modifiying rocket stages to be recovered, a recovery apparatus could be used instead. I'd envisage a formation of hot air balloons with a large net suspended between them, positioned in the way of the falling booster. I'm not sure how large the impact footprint of a falling first stage is, though, so this idea might be non-viable if the footprint is, say, more than 5km square.
Waiting for joy and raptor

Offline ryan mccabe

  • Full Member
  • *
  • Posts: 114
  • Liked: 0
  • Likes Given: 0
Re: Reusable First Stages and Boosters
« Reply #17 on: 09/13/2007 09:14 PM »
The easiest way is just to make something robust and self-contained. Once you start depending on mid-air captures, tethers, etc, you introduce new ways for the system to fail. I would suggest:

Stage your vehicle as low as possible (say 120-130 seconds into ascent) to minimize re-entry loads and down-range distance from your processing facility. Rely on ballistic re-entry. Parachutes deploy from the tail of the rocket stage so that it enters the water nose-first. Hatches open in advance to allow sea water to flood one of your oxidizer (or fuel) tanks to balance the vehicle so the engine never enters the water. Recovery ships hoist the stage aboard and rinse the tanks with fresh water ASAP.

If second stage re-use also happens to be important, develop a winged vehicle to ride atop the first stage.

Offline tnphysics

  • Regular
  • Full Member
  • ****
  • Posts: 1073
  • Liked: 0
  • Likes Given: 0
Re: Reusable First Stages and Boosters
« Reply #18 on: 09/13/2007 09:48 PM »
A titanium upper stage might not need a heat shield for re-entry because it has such a high drag to mass ratio that peak heating might be only 1100 degrees Celsius.

Offline BarryKirk

  • Member
  • Full Member
  • **
  • Posts: 260
  • Liked: 1
  • Likes Given: 0
Re: Reusable First Stages and Boosters
« Reply #19 on: 09/14/2007 03:42 PM »
How about making the interstage ring retained by the lower stage.

Use that as a crumple zone when hitting the water?

I like the idea of using the upper tank on the booster stage as ballast to keep the engines out of the drink.

Tags: