Community > Forum > Technology & Science > Bundles of rockets - what about it?

Bundles of rockets - what about it?

Posted by: Ekkehard Augustin - Mon Mar 21, 2005 1:51 pm
Post new topic Reply to topic
 [ 16 posts ] 
Bundles of rockets - what about it? 
Author Message
Moderator
Moderator
avatar
Joined: Thu Jun 03, 2004 11:23 am
Posts: 3745
Location: Hamburg, Germany
Post Bundles of rockets - what about it?   Posted on: Mon Mar 21, 2005 1:51 pm
According to their German-only report http://www.tim-report.de/Project_Enterprise.pdf the Talis Institute is thinking about using their microsat-oriented rocket "Enterprise" for manned suborbital flights too.

What are comparisons of rocket-bundles to one whole rocket resulting in technically and technologically? Are they dangerous, suboptimal etc. or are they reasonable? ...

...



Dipl.-Volkswirt (bdvb) Augustin (Political Economist)


Back to top
Profile
Moon Mission Member
Moon Mission Member
avatar
Joined: Tue Feb 10, 2004 2:56 am
Posts: 1104
Location: Georgia Tech, Atlanta, GA
Post    Posted on: Tue Mar 22, 2005 1:42 pm
They're suboptimal (because you have a higher dry weight due to more equipment), and they're less dangerous (because there's less of a chance that the entire thing will blow up).

The big problem with a bundle is getting them all to light at almost exactly the same time -- a very fancy trick, and one that is rarely pulled off without a hitch. Bundles are generally seen as overcomplicated, although somewhat safer than a single rocket.

_________________
American Institute of Aeronautics and Astronautics
Daniel Guggenheim School of Aerospace Engineering

In Memoriam...
Apollo I - Soyuz I - Soyuz XI - STS-51L - STS-107


Back to top
Profile
Space Station Member
Space Station Member
User avatar
Joined: Mon Apr 12, 2004 4:16 am
Posts: 322
Post    Posted on: Tue Mar 22, 2005 4:14 pm
I tend to think of a bundled system as far more dangerous. Any time you add to the complexity of a system the possibility of failure increases. (For instance, though the Shuttle SRB's have a good track record, as far as boosters go, it only took one to take down the entire STS stack). As Spacecowboy mentioned, it increases mass as well.

I suppose I am thinking of a "Bundle" as many engines, as upposed to a multi-engine system such as the S-V's first stage or STS's multiple SSMEs. I have a feeling, when all is said and done, that the D-IV might get the nod for Project Constellation because it doesn't rely on bundled solid boosters.

Better, and cheaper in the long run, to use a big-dumb booster, but I guess if you've already got the small rocket, and you can't afford to develop something new from scratch, the bundling option is enticing. To me it's a desperation move.


Back to top
Profile YIM
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Oct 05, 2004 5:38 pm
Posts: 1361
Location: Austin, Texas
Post    Posted on: Tue Mar 22, 2005 4:30 pm
spacecowboy wrote:
The big problem with a bundle is getting them all to light at almost exactly the same time
That's for sure. I still remember launching a 4 engine cluster model rocket. The rocket took off before all the engines ignited, pulling the igniter out of some of the engines. As a result there was not enough power to take the rocket high enough and the parachute deployed too late. Crash!


Back to top
Profile WWW
Moon Mission Member
Moon Mission Member
avatar
Joined: Tue Feb 10, 2004 2:56 am
Posts: 1104
Location: Georgia Tech, Atlanta, GA
Post    Posted on: Wed Mar 23, 2005 1:24 pm
And the sad thing is that the Estes rocket ignition system is not much worse, reliability-wise, than the systems used by orbital launch vehicles.

_________________
American Institute of Aeronautics and Astronautics
Daniel Guggenheim School of Aerospace Engineering

In Memoriam...
Apollo I - Soyuz I - Soyuz XI - STS-51L - STS-107


Back to top
Profile
Moderator
Moderator
avatar
Joined: Thu Jun 03, 2004 11:23 am
Posts: 3745
Location: Hamburg, Germany
Post    Posted on: Wed Mar 23, 2005 1:45 pm
To detail my initial question by a question I should have asked before the initial one - would the use of a microsat-orineted rocket for suborbital passenger flight require a modification to be able to bundle such rockets or can bundles avoided by alternative modifications?



Dipl.-Volkswirt (bdvb) Augustin (Political Economist)


Back to top
Profile
Space Station Member
Space Station Member
User avatar
Joined: Mon Apr 12, 2004 4:16 am
Posts: 322
Post    Posted on: Wed Mar 23, 2005 4:00 pm
There woulld have to be modifications. You can't just strap them together and bolt a crew cabin on the top. It's a completely new vehicle at that point.


Back to top
Profile YIM
Moderator
Moderator
avatar
Joined: Thu Jun 03, 2004 11:23 am
Posts: 3745
Location: Hamburg, Germany
Post    Posted on: Wed Mar 23, 2005 4:19 pm
Okay - but is it possible to modify a microsat-oriented rocket in a manner that bundling of them isn't required or would that end up with a completely new rocket which cannot be considered to be a modification of a microsat-rocket any longer but would be a complete new rocket merely?



Dipl.-Volkswirt (bdvb) Augustin (Political Economist)


Back to top
Profile
Space Station Member
Space Station Member
User avatar
Joined: Mon Apr 12, 2004 4:16 am
Posts: 322
Post    Posted on: Wed Mar 23, 2005 10:28 pm
I don't know of any active launchers that I would call "microsat" launchers at the moment, though there are very small launchers.

Many of these accelerate very quickly. It might be fun, up to a point (it's not fun when you pass out)

Now, take the Pegasus. It's only 1.2M in diameter. Anything you put atop it is going to bulge out quite a bit which may or may not be a problem. (see Atlas V). But at some point, the CG is going to become interesting


Back to top
Profile YIM
Spaceflight Participant
Spaceflight Participant
avatar
Joined: Thu Sep 09, 2004 4:58 pm
Posts: 95
Location: London, UK
Post    Posted on: Thu Mar 24, 2005 12:57 pm
The Pegasus only launches very small payloads, it doesn't need to be very wide - and the Atlas generally only uses the wider fairing in missions where it is also using solid rocket boosters, to allow it to launch larger weights. You can put a wider fairing on, but it's prefered not to.

_________________
Sev


Back to top
Profile
Space Station Member
Space Station Member
User avatar
Joined: Mon Apr 12, 2004 4:16 am
Posts: 322
Post    Posted on: Thu Mar 24, 2005 3:22 pm
I know. Ekkehard was hypthesizing, I think, about putting a manned capsule on a microsat launcher. Pegasus was the smallest one I could think of at the moment.

Scout was smaller. Their may be a few other smaller ones that I am not aware of, besides vaporware.


Back to top
Profile YIM
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Oct 05, 2004 5:38 pm
Posts: 1361
Location: Austin, Texas
Post    Posted on: Thu Mar 24, 2005 3:28 pm
bad_astra wrote:
Their may be a few other smaller ones that I am not aware of, besides vaporware.
How about the Jupiter-C?
http://en.wikipedia.org/wiki/Jupiter-C_%28rocket%29
It used several stages, some of which were clusters of small solid rocket motors. The payload would be smaller than a person though, much less a person plus space craft.

(EDIT) The Vanguard rocket was pretty small too.
http://en.wikipedia.org/wiki/Vanguard_rocket


Back to top
Profile WWW
Space Station Member
Space Station Member
User avatar
Joined: Mon Apr 12, 2004 4:16 am
Posts: 322
Post    Posted on: Thu Mar 24, 2005 3:35 pm
Well I was thinking of ones that currently exist.


Back to top
Profile YIM
Moderator
Moderator
avatar
Joined: Thu Jun 03, 2004 11:23 am
Posts: 3745
Location: Hamburg, Germany
Post    Posted on: Thu Mar 24, 2005 4:31 pm
Hello, bad_astra,

I haven't been hypothesizing - Talis is in fact speaking of offering suborbital flights by capsule on top of their microsat-rocket. They are speaking of doing it by a modified version of their "Enterprise"-rocket.

This caused my questions and this thread.

Concerning the microsat-rocket currently under development they are mentioning the large market for such rockets in the nearby future. So they expect to have very much launches of that rocket. It's semi-reusable. They will NOT have that number of launches at the suborbital market in the same nearby fiuture I suppose. Because of this my first thought was that they might think of modify "Enterprise for bundling to be able to launche a manned capsule or vehicle.

Al this and perhaps more I want to stress here.



Dipl.-Volkswirt (bdvb) Augustin (Political Economist)


Back to top
Profile
Moderator
Moderator
avatar
Joined: Thu Jun 03, 2004 11:23 am
Posts: 3745
Location: Hamburg, Germany
Post    Posted on: Mon Apr 25, 2005 12:08 pm
Just to add a detail - the modified version of Enterprise for suborbital flight will be single-staged if they realy do that modification.



Dipl.-Volkswirt (bdvb) Augustin (Political Economist)


Back to top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 16 posts ] 
 

Who is online 

Users browsing this forum: SANEAlex and 20 guests


© 2014 The International Space Fellowship, developed by Gabitasoft Interactive. All Rights Reserved.  Privacy Policy | Terms of Use