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Old 08-18-2008, 12:51 AM
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CPMcGraw CPMcGraw is offline
Join Date: Mar 2005
Location: Mobile, Alabama
Posts: 5,357
Exclamation New Plan -- Flis Ram Scoop Technology Demonstrator

Ever since I saw Jim Flis' "Borealis" design, it has made me think more than a few times about how he used those narrow rings as "tube fins". I've been wanting to do something similar. This new design is obviously more than a little inspired by Jim's imagination, meaning it just stood out to be... um... imitated (yeah, that's the ticket... )...

To be fair, there is another design somewhere here on YORF using similar narrow tube fins, and that design has some additional bearing on how this design was worked out. (Solomoriah, didn't you share something with us a few years ago like this?)

To put this model into Jim's universe and story line, it represents a small demonstration ship that was built and flight-tested long before any of his fleet of capital ships using "Ram Scoop" technology came on-line. It would have been used to gather engineering data and to work out any major bugs and 'gotchas' before committing greater resources.

This design uses the A10-3T and still puts in a respectable 244' of altitude. However, I have to give this caveat about the way the design came together in RockSim: The fourth ring, which ties the outer rings to each other, is modeled as an INSIDE TUBE, and not as a RING FIN. This may affect the way the real-world model actually performs. Using the RF method, the altitude is cut in half and the Dv number shoots well above 20 FPS. Using the IT method, the Dv drops to a comfortable 2 FPS. After the experience with the BARCLONE Andromeda design, and with Jay's Tau Zero prototype, I am convinced the RockSim RF routine is in error, but by how much I cannot say. Here's the reason I say this: When I delete that ring, the altitude jumps up to 253', and the Dv only gets to a little over 3 FPS, in a run of 10 simulations. In other words, as an IT it has a documented effect, but it's not detrimental.

Length: 19.80"
Diameter: 0.908" (ST-8)
Fin Span: 7.24"
Weight: 1.27 oz

The A3-4T, 1/2A3 and 1/4A3 are not recommended.


Magic number now at 30...
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Craig McGraw

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