aerodynamic experts only question
08-06-2013, 11:04 AM
#1
aerodynamic experts only question
Ok here it is.
I am building an old ZIA Models/Flight line F-106 delta dart. The wing has a 42" span made out of solid 1/4 sheet wood. No airfoil. The kit has 1/2 wide plywood strips that glue on the tip and a 1/4" tall strip that glues on top of the wing to make a chine/strake. I would like to put the wing strip on the bottom to look better but not sure if it was designed to help with producing lift if installed on the top of the wing or to just stiffen the wing. I know with this flat wing there is a very small AoA angle that will produce lift before it turns into a kite per say.
So build it as designed or will it matter if the 1/4" tall strip is on the bottom of the wing? For the wing tip what will help the most with lift? having a 1/4" above the wing tip or 1/4" below the wing? Should I go with a larger wing tip?
I am building an old ZIA Models/Flight line F-106 delta dart. The wing has a 42" span made out of solid 1/4 sheet wood. No airfoil. The kit has 1/2 wide plywood strips that glue on the tip and a 1/4" tall strip that glues on top of the wing to make a chine/strake. I would like to put the wing strip on the bottom to look better but not sure if it was designed to help with producing lift if installed on the top of the wing or to just stiffen the wing. I know with this flat wing there is a very small AoA angle that will produce lift before it turns into a kite per say.
So build it as designed or will it matter if the 1/4" tall strip is on the bottom of the wing? For the wing tip what will help the most with lift? having a 1/4" above the wing tip or 1/4" below the wing? Should I go with a larger wing tip?
08-07-2013, 10:06 PM
#2
Join Date: Oct 2002
Location: Chilliwack, BC, CANADA
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If the strip is glued to the top of the wing then it's not really a chine or strake. But if it's about half the span out from the fuselage it may be a flow straightener fence similar to that found on the Mig 15 as one example. If this isn't the case then a picture of that portion of the plans would aid us in figuring out what it is you've got.
08-08-2013, 05:11 AM
#3
Senior Member
Interestingly the original didn't seem to have such strips, at least on the top surface. There are equipment rails under the wings and strips outboard those rails as well.
08-08-2013, 11:26 AM
#4
the plans show it at the mid span on each wing. I am not asking what the name of this piece is just is it better to have on the top or the bottom. The plans show it on top of the wing. remember this plan has no air foil. I would like to have it on the bottom of the wing if it isnt needed for aerodynamics on the top.
My dad and I flew this in the late 80's and flew fine as long as the engine was running at half power or better. less than that and they turned into a guided rock.
My dad and I flew this in the late 80's and flew fine as long as the engine was running at half power or better. less than that and they turned into a guided rock.
08-13-2013, 08:42 AM
#7
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Again, a picture of this portion of the plans would aid us in better understanding if the strip is for aerodynamic reasons or simply to stiffen the flat wing.
All in all if the strip extends out in front of the leading edge I'd say that the reason it's there is aerodynamic. If it rounds up and back it's likely more to stiffen and ensure the wood stays flat. In the second case it SHOULD be OK to move it to the underside.
The other option is to build as per plans, try it, then cut it away and try it on the bottom. Use basic carpenter's "yellow" glue and glue a strip of printer paper between the wing and the stiffener. This will hold well enough for flying. But later on you can easily wedge a knife blade into the paper and split away the stiffener to leave have the paper on the wing and half on the stiffener with essentially zero damage to the wood of either part. Then glue it on with the same system to the bottom and try it that way.
Assuming you're using iron on film as a covering it's a snap to leave slots in the covering for gluing on the stiffener and then iron on a patch stripe to cover the side with no stiffener.
All in all if the strip extends out in front of the leading edge I'd say that the reason it's there is aerodynamic. If it rounds up and back it's likely more to stiffen and ensure the wood stays flat. In the second case it SHOULD be OK to move it to the underside.
The other option is to build as per plans, try it, then cut it away and try it on the bottom. Use basic carpenter's "yellow" glue and glue a strip of printer paper between the wing and the stiffener. This will hold well enough for flying. But later on you can easily wedge a knife blade into the paper and split away the stiffener to leave have the paper on the wing and half on the stiffener with essentially zero damage to the wood of either part. Then glue it on with the same system to the bottom and try it that way.
Assuming you're using iron on film as a covering it's a snap to leave slots in the covering for gluing on the stiffener and then iron on a patch stripe to cover the side with no stiffener.
