Ye Olde Rocket Forum

Go Back   Ye Olde Rocket Forum > Weather-Cocked > FreeForAll
User Name
Password
Auctions Register FAQ Members List Calendar Today's Posts Search Mark Forums Read


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 09-04-2009, 10:31 PM
STRMan's Avatar
STRMan STRMan is offline
Master Modeler
 
Join Date: Nov 2007
Posts: 873
Default Staging clustered engines to a single engine

The Fat Boy thread got me thinking. If one wished to do a model like this, but wanted to have a two engine cluster in the lower stage, would a two engine cluster in the booster reliably ignite a single engine in the sustainer? If the engines are not directly in line, will that prevent staged ignition? Would some kind of reverse reducer be necessary in the booster to funnel the burning particles up into the sustainer? I'm just kind of thinking out loud here.
__________________
"AND I hope they are from the planet of the "Chunk spunky Mary-Lou Retton clones". - Ironnerd

"Those who trade liberty for security have neither" - Benjamin Franklin

"Semroc is almost always the answer" - Stefanj

www.paulsavia.com

www.soundclick.com/paulsavia
Reply With Quote
  #2  
Old 09-04-2009, 10:37 PM
Intruder's Avatar
Intruder Intruder is offline
Craftsman
 
Join Date: Oct 2007
Location: Huntingdon, Tennessee
Posts: 278
Default

With the motors side by side with a bit of distance I would think so. If the motors were angled in so that they are aimed at the sustainer, that would work also. A reducer or funnel would have to be pretty heavy duty and/or have a removable shield or else it will get torched pretty quick.
Reply With Quote
  #3  
Old 09-04-2009, 11:19 PM
stefanj stefanj is offline
Master Modeler
 
Join Date: Mar 2005
Location: Hillsboro, OR
Posts: 2,847
Default

I've seen this done.

A guy named Dale in Oregon Rocketry made a sturdy-looking two stager. BT-70 or BT-80, not terribly long. "Alpha" shaped fins.

The booster had two D motors, with simple ductwork to get the sparks up to the single upper stage nozzle.

It has been a few years since I saw it, but I seem to recall that it had a hatch for the parachute on the side of the booster. When the booster separated that hatch was free to flop open.
Reply With Quote
  #4  
Old 09-05-2009, 06:49 AM
STRMan's Avatar
STRMan STRMan is offline
Master Modeler
 
Join Date: Nov 2007
Posts: 873
Default

You know, I really like the idea of the angled engines on the booster section. That would even help in the event that only one engine lights, keeping the thrust through the rockets CG. Great idea. I'm starting to get the "experimentation bug" now!
__________________
"AND I hope they are from the planet of the "Chunk spunky Mary-Lou Retton clones". - Ironnerd

"Those who trade liberty for security have neither" - Benjamin Franklin

"Semroc is almost always the answer" - Stefanj

www.paulsavia.com

www.soundclick.com/paulsavia
Reply With Quote
  #5  
Old 09-05-2009, 08:10 AM
jflis jflis is offline
FlisKits, Inc.
 
Join Date: Mar 2005
Location: Merrimack, NH (wish it were Alaska :) )
Posts: 795
Default

A rocketeer named Jason Toft did something very similar for a design on the month entry at FlisKits. You can find his entry by clicking this link.

His Sandhawk has a 3 motor cluster, but one motor was used for recovery deployment while the two other motors were used for sustainer ignition.
__________________
FlisKits, Inc.
http://fliskits.com/
Model rocket kits and MORE!

Toad's Tavern - http://toadstavern.com/
Personal site - http://jflis.com/
Reply With Quote
  #6  
Old 09-05-2009, 08:08 PM
Rocketflyer's Avatar
Rocketflyer Rocketflyer is offline
Member in Good Standing!
 
Join Date: Sep 2006
Posts: 1,209
Default

A member of our club does it. Channels three engines to the single upper stage using the "funnel" technique. Coats it with medium grade CA. Works pretty good too.
__________________
Enjoy life, it has an expiration date.
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump



All times are GMT -5. The time now is 05:16 PM.


Powered by: vBulletin Version 3.0.7
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Ye Olde Rocket Shoppe © 1998-2024