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General control line discussion => Open Forum => Topic started by: Mike Griffin on May 09, 2013, 01:01:41 PM

Title: Laying out a Profile Fuselage from Ted Fancher's article
Post by: Mike Griffin on May 09, 2013, 01:01:41 PM
In reading Ted Fanchers article on the imitation, he gives the dimensions of where the thrust line, center of wing and stab should be on a profile fuselage and according to his article they are as follows:

 To establish the thrust line, Measure down 1 5/16 from the top edge and draw a straight line the length of the board.

To establish the centerline of the wing, drop down 1 inch from the thrust line and draw another line the length of the board.

To establish the leading edge of the wing, measure back from the nose of the board 5 7/8 inches and draw a vertical line the width of the board.  Trace the root wing section on this line.

The center line of the stabilizer is the same as the thrust line.  Measure back from the nose
29 5/8 inches on the thrust line and draw a vertical line to establish the nose of the horizontal stabilizer.


Is there a similar guideline for a full body fuselage?

Thanks

Mike
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: Howard Rush on May 09, 2013, 01:56:52 PM
A piece of string is 47 inches long.  Is there a similar guideline for 14-gauge copper wire?
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: RandySmith on May 09, 2013, 02:04:15 PM
In reading Ted Fanchers article on the imitation, he gives the dimensions of where the thrust line, center of wing and stab should be on a profile fuselage and according to his article they are as follows:

 To establish the thrust line, Measure down 1 5/16 from the top edge and draw a straight line the length of the board.

To establish the centerline of the wing, drop down 1 inch from the thrust line and draw another line the length of the board.

To establish the leading edge of the wing, measure back from the nose of the board 5 7/8 inches and draw a vertical line the width of the board.  Trace the root wing section on this line.

The center line of the stabilizer is the same as the thrust line.  Measure back from the nose
29 5/8 inches on the thrust line and draw a vertical line to establish the nose of the horizontal stabilizer.


Is there a similar guideline for a full body fuselage?

Thanks

Mike



NO  the dimensions you gave from Ted  works for that airplane, there are  very many things, criteria, percentages etc, that will change the dimensions of a full body stunt plane layout.. , Or even a profile, the dimensions you gave  may, or may NOT  work, for other profiles.

Example hang a pipe, coupler, tricycle landing gear under the profile, among others,or change the tips, rake, TE or LE and you change the Verticle or Horizontal CG. That can affect where the centerline of your wing should be...or where the tips should;d be, or where the leadout guide can be in the tip. There are other examples but you see the problem

Randy
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: Tim Wescott on May 09, 2013, 02:17:07 PM
Is there a similar guideline for a full body fuselage?

There's been a lot of discussion over the years here about what counts.

I would think that it's fairly safe to pick an aircraft that you can trust, then copy its aerodynamics with your own aesthetics.  Meaning, build the wing and tail the same, and put them in the same place as the wings and tail of the prototype.  Ditto with the engine or motor.  Then make the fuselage and rudder shape match your dreams, and if you're feeling bold change the shape of the wingtips and horizontal stab.

Doing so should at least get you in the ballpark, even if it doesn't end up being a world-beating aircraft.

The important factors that I know about, to replicate the performance of the original, are:


I'm sure there's more -- but if you copy that you should have a chance at something with tolerable performance.
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: Mike Griffin on May 09, 2013, 05:40:18 PM
A piece of string is 47 inches long.  Is there a similar guideline for 14-gauge copper wire?



Yeah Howard and you can't stick butter up a wildcat's ass with a hot poker... about as relevant as your answer......
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: Bob Whitely on May 09, 2013, 08:46:21 PM
Now that's funny!!!!!  RJ
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: wwwarbird on May 09, 2013, 09:35:09 PM
Is there a similar guideline for a full body fuselage?

Thanks

Mike


 Yes, just do it twice, on thinner wood. D>K
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: Tim Wescott on May 09, 2013, 09:59:56 PM
Yes, just do it twice, on thinner wood. D>K

That would likely mess up the vertical center of gravity.
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: wwwarbird on May 09, 2013, 10:15:16 PM
That would likely mess up the vertical center of gravity.

 Um, no. "Doing it twice" on 1/8" would simply give you a pair of fuselage sides. Add a firewall and some bulkheads and you're on your way to your "full body" fuselage.
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: Howard Rush on May 09, 2013, 10:36:41 PM
Yeah Howard and you can't stick butter up a wildcat's ass with a hot poker... about as relevant as your answer......

We had the relevant conversation last time.  The upshot was that Imitation numbers are relevant to Imitations.  Extrapolation beyond that is nontrivial for reasons that folks spent a lot of effort explaining. 
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: Mark Scarborough on May 09, 2013, 11:38:07 PM


Yeah Howard and you can't stick butter up a wildcat's ass with a hot poker... about as relevant as your answer......


actually, Mike, no offense intended, but its really as relevant  as your question,,
remember, the airplane is a SYSTEM,, all the measurments are interdependent,, what works on a plane powered by a 40VF would be expected to be different than that which will work on a fox 35 powered airplane,,
That layout was for THAT airplane,, and as such was intended to be simplistic,, or so is my take
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: Allen Brickhaus on May 10, 2013, 05:47:32 AM
The Imitation is an inverted engine model.  This will not work for a side mounted engine.  Please read the Encore 40 twin article in Flying Models to see what can be done to transfer an inverted engine model to a side mounted engine.  The article is in the October 2007 FM.

Allen
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: Mike Griffin on May 10, 2013, 10:15:51 AM
Hey Howard

I like you have a twisted sense of humor sometimes....no offense intended and I apologize if you took it that way.....

Mike
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: wwwarbird on May 10, 2013, 09:36:08 PM
Hey Howard

I like you have a twisted sense of humor sometimes...

Mike

 I think Howard has an upcoming HBO special, or at least he should...
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: wwwarbird on May 10, 2013, 09:44:25 PM

remember, the airplane is a SYSTEM,, all the measurments are interdependent,, what works on a plane powered by a 40VF would be expected to be different than that which will work on a fox 35 powered airplane,,

 That is a great way of putting it simply and answering the question Mark. There are no universal "cookie cutter" design specs for what we do. The preferences of the individual operating the handle also comes into play. Some guys love and swear by the performance of a certain design and/or combo, while others may not care for it at all. That's why the experimentation never ends.
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: Mike Lauerman on May 11, 2013, 04:25:16 PM
Howard is indeed the Ben Stein of Advanced Control Line.
Title: Re: Laying out a Profile Fuselage from Ted Fancher's article
Post by: Balsa Butcher on May 12, 2013, 10:39:19 AM
Don't know if this is what you were thinking of but this is an electric by the numbers full bodied Imitation. Built by Bob Duncan, one of the best builders and finishers on the West Coast.  8)