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General control line discussion => Open Forum => Topic started by: Motorman on September 12, 2016, 04:43:09 PM

Title: Banshee B40
Post by: Motorman on September 12, 2016, 04:43:09 PM
Anybody running a Brodak 40 on a Sig Banshee? I've got an electric Banshee I'm converting back to glow and a couple of B40's so have to build the nose out longer. Was wondering how long is your nose from the leading edge to the drive washer. Going to start with a 4oz tank and a plastic prop. Plane has monokote and was 45oz with the electric system. The plans say 9.5" for the Fox 35 without muffler. Figure 7.5" for the B40 with factory muffler?

MM
Title: Re: Banshee B40
Post by: Tim Wescott on September 12, 2016, 05:19:10 PM
Dunno how to answer the question, but if no one comes through the way that you answer the question is to dummy up everything onto the nose of the airplane in such a way that it (A) doesn't have too much weight in the clamps and whatnot, and (B) can be slid forward and backward.  Get everything hung more or less where it'll go on the finished plane, toss in half an ounce of lead to account for the wood and glue, then measure where it is when it balances.
Title: Re: Banshee B40
Post by: TigreST on September 12, 2016, 06:38:04 PM
Please correct me if I'm wrong but... Was it not part and parcel of a Banshee build to shorten the nose for internal combustion operations not that long ago?  I've got memories (vague mind you?) of posts and such about cutting the nose down from the stock length?  Or maybe it was "move the wing forward"?  Sorry to confuse the issue.  Hmm...just how heavy is an electron power package?  There are more than one Banshee build and mod threads out there I think.  Maybe google can find them? (I have not tried that as yet).

Tony.

edit: Heres a couple links :

http://stunthanger.com/smf/open-forum/sig-banshee-mods/

http://www.clstunt.com/htdocs/dc/dcboard.php?az=show_topic&forum=103&topic_id=356578

http://www.hippocketaeronautics.com/hpa_forum/index.php?topic=16729.0;wap2

http://forum.amadistrictvii.org/viewtopic.php?f=31&t=2072

ps: I've never built or flown a Banshee so I can off no real world data, sorry bout that.
Title: Re: Banshee B40
Post by: Tim Wescott on September 12, 2016, 06:59:01 PM
The original Banshee was designed for an unmuffled Fox 35 (which is pretty light), and to 1970's design rules (which called for a much shorter tail volume than is popular now).  If you're putting a muffled just-about-anything on it you'll need to shorten the nose, and to make it more competitive you'll want to lengthen the tail -- so, move the wing forward.
Title: Re: Banshee B40
Post by: Dennis Moritz on September 13, 2016, 12:09:28 PM
See if you can find a Twister. Use that nose moment for reference. I think the Twister and Banshee share the same wing. Twister's nose is shorter. Wait. Brodak 40s are light are they not. Weigh similar to a Fox 35. If flying without a muffler, Brodak may work ok on plane as is.
Title: Re: Banshee B40
Post by: Paul Allen on September 13, 2016, 05:40:25 PM
Motorman
             Banshee with Brodak 40,  203mm or 8" from leading edge to front face of prop driver.
Title: Re: Banshee B40
Post by: Motorman on September 13, 2016, 06:54:36 PM
Thank you Paul.


MM
Title: Re: Banshee B40
Post by: Tim Wescott on September 13, 2016, 06:59:36 PM
See if you can find a Twister. Use that nose moment for reference. I think the Twister and Banshee share the same wing. Twister's nose is shorter. Wait. Brodak 40s are light are they not. Weigh similar to a Fox 35. If flying without a muffler, Brodak may work ok on plane as is.

Not the same wing -- the Banshee wing is definitely of lower aspect ratio than the Twister.
Title: Re: Banshee B40
Post by: Randy Cuberly on September 13, 2016, 08:41:24 PM
Not the same wing -- the Banshee wing is definitely of lower aspect ratio than the Twister.

Yes and the airfoil is a little thinner also. 

Randy Cuberly
Title: Re: Banshee B40
Post by: Chris Fretz on September 14, 2016, 03:56:34 AM
Motorman
             Banshee with Brodak 40,  203mm or 8" from leading edge to front face of prop driver.
That is a pretty cool looking tank, bought or made? Is that cork behind it?
Title: Re: Banshee B40
Post by: Paul Allen on September 14, 2016, 04:06:08 PM
That is a pretty cool looking tank, bought or made? Is that cork behind it?
The tank is home made a copy of a double wedge tank that Brian Eather use to make
many years ago,and it has rubber impregnated cork behind it.
Title: Re: Banshee B40
Post by: EddyR on September 14, 2016, 06:43:51 PM
MM     7.5 to 8.0" is correct. I had a stock one many years ago and it was nose heavy with a Fox .19 with muffler.
Ed