Ye Olde Rocket Forum

Go Back   Ye Olde Rocket Forum > BARCLONE > Designer's Studio
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 08-15-2009, 12:45 PM
blindeye2 blindeye2 is offline
Junior Rocketeer
 
Join Date: Jun 2009
Posts: 28
Default Craig McGraw Shuttle Exeter

Has anyone done a Rocksim of Craig McGraw 's Shuttle Exeter?
Would you share it if you have?

http://barclone.rocketshoppe.com/concept.htm

Bob
Blindeye2
Reply With Quote
  #2  
Old 08-15-2009, 01:45 PM
CPMcGraw's Avatar
CPMcGraw CPMcGraw is offline
BARCLONE Rocketry
 
Join Date: Mar 2005
Location: Mobile, Alabama
Posts: 5,357
Default

Would you believe I have not done one myself?

I'm working on it now. It will be interesting to see if one of my pre-RS designs can hold up to simulation testing...
__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
BARCLONE Blogsite -- http://barclone.wordpress.com
BARCLONE Forum -- BARCLONE Forum

BARs helping BARs

SAM 0044
AMA 352635
Reply With Quote
  #3  
Old 08-15-2009, 01:55 PM
blindeye2 blindeye2 is offline
Junior Rocketeer
 
Join Date: Jun 2009
Posts: 28
Default The Master Confesses

The Master Confesses. What do we left to beleive in?
Bob
Reply With Quote
  #4  
Old 08-15-2009, 02:48 PM
CPMcGraw's Avatar
CPMcGraw CPMcGraw is offline
BARCLONE Rocketry
 
Join Date: Mar 2005
Location: Mobile, Alabama
Posts: 5,357
Exclamation

Quote:
Originally Posted by blindeye bob
The Master Confesses. What do we left to beleive in?


Shucks, if you thought that was confession...

As it turns out, I think I may have tried to do this one in RockSim several years and two versions ago. This design will not simulate. There is still a problem within RS9 when you try to simulate those engine cheek cowls, if they interfere with the engine tube (which happens in this design). RockSim has no way to "ignore" the material of those cowl tubes which intersect with the inside area. When the design is loaded up, the engine finds itself with those tubes running through it, and you get NAN.

Having said that, I think I can still get a reasonable projection of what the design might do. As-is, the design is slightly unstable. This is due to the forward position of those main wings. The design needs 1/2 oz of ballast just behind the nose cone shoulder to get the margin up to 1.41 on a C6-5.

Some adjustments made in the simulation:
  1. The lower sub-fins were enlarged by 20%.
  2. The rear section of the intake spike (BT-5T) was eliminated.
  3. The intake cones were changed to BNC-5AX (2.25"), and the shoulders were removed.
  4. Both spikes can be obtained from one cone.
  5. The intake tubes were lengthened to 7.75", to account for the additional length of the curved intake pieces.

With the additional ballast, the model should be stable, and should fly reasonably well on B and C power. Until we get some way of forcing RS to ignore the inside material from the intakes, this will continue to give us a NAN simulation.
Attached Thumbnails
Click image for larger version

Name:  Shuttle Exeter 3D.jpg
Views: 73
Size:  51.4 KB  
Attached Files
File Type: rkt Shuttle Exeter.rkt (65.2 KB, 62 views)
__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
BARCLONE Blogsite -- http://barclone.wordpress.com
BARCLONE Forum -- BARCLONE Forum

BARs helping BARs

SAM 0044
AMA 352635
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 09:28 PM.


Powered by: vBulletin Version 3.0.7
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Ye Olde Rocket Shoppe 1998-2019