Wright Stuff B

[fleet130]

From the top of EVERY event page on soinc.org:

The information below should not be interpreted as an interpretation or extension of the rules. The official rules in the current Rules Manual take precedence.

This refers to the information linked to on those pages. Posting a direct link to the scoresheet here (or anywhere else) places it out of context and bypasses this important message.

[Pleiades]

Yeah, what fleet said is correct. It sounded like he basically wanted an outline of the rules which the score sheet provided. It should NOT be used in place of the rules but he mentioned he'll be receiving the rules shortly but he wanted to get a head start on building.

[bob3443]

Has anyone used TAN indoor contest rubber?
Also about how much would 25inches of 3/32 rubber weigh?

[andrewwski]

The rubber you want is from Tan. It's called Tan Super Sport. That's the only rubber you want to use.

I'd guess that 25" of 3/32" would weigh a few grams. Maybe around 3.

[bob3443]

Has anyone tryied Easy Built Lite paper for the wing and stabilizer? its on http://www.easybuiltmodels.com/ebl.htm It does seem very heavy at 6.5 grams a sheet.

[carneyf1d]

dude 6.5 grams per sheet would consume all of your building weight. its wayyyy too heavy. now, as for rules go.... Dont be stupid, read the OFFICIAL RULES and follow them. its two pages, like 2 minutes of reading, so just read them.
people have been asking about stabilizers....
heres some definitions and info that you might find useful...
A plane consists of a wing, fuselage, prop, stab, fin, tailboom.
The chord is the distance from leading edge to trailing edge...if you cant determine which sides are the LE and TE then you need major help. The span is the distance from the right and left side of the wing. Heres a hint...building a massive wing with a large chord is going to increase the wing aspect ratio, AR, which is chord^2 / wing area. drag is directly related to the dynamic pressure and AR, and since you cant influence the dynamic pressure during your flight day, all you can do is design your plane to have a low enough AR, although keep in mind that the more wing area the more lift.
Also, you only need one horizontal stabilizer, and possibly one or two vertical stabilizers, known also as fins, depending on whether you want to make tip plates or not. (i prefer tip plates on the stab and wing because they create a dihedral effect without the plane changing flight paths. If you want me to explain more about this just pm me.)
anyways...the whole reason for the stab is to set the moments of the plane to 0. the tail causes a moment that opposes the wing. therefore the farther away from the Center of Gravity the stab is, the less area it has to be to create the same amount of moment. the less area means less drag.
anyways, i could go on for days about planes. however, i hope somebody out there finds this useful. and everybody feel free to correct me if i made a incorrect statement...it is 2:30 in the morning afterall
in addition, anybody needing more assistance can contact me through AIM or just pm me.
-Carney

[carneyf1d]

one more important thing. the endurance of a plane is related to the efficiency of the propeller and (coefficient of lift)^(3/2)/(coefficient of drag).

the overall wing coefficient of lift is based on the airfoil coefficient of lift. Therefore, changing the camber in your airfoil can drastically change your times by increasing the coefficient of lift.
and also, make a kick*** propeller to increase efficiency. i wont go on about this subject because it goes really in depth. however, im sure you can do a little research on your own.


by the way, im gonna update the wiki on wright stuff very very soon. possibly tomorrow. stay tuned for some good info on there.

[jander14indoor]

dude 6.5 grams per sheet would consume all of your building weight. its wayyyy too heavy. <SNIP>-Carney

Whoops, check your math. You'll only need a portion of that 20 inch by 30 inch sheet to cover a Wright Stuff plane. By my quick calculation just under 1.0 gm for covering. A manageable budget for this size plane. Not the lightest available covering, but light enough to leave plenty of room for a good structure and still hit the overall weight budget of 7.0 gm.

Look, use whatever reasonably light covering you can find. Tissue, light shopping bags, indoor film, whatever. Lighter covering means heavier/stronger structure, heavier means lighter/weaker structure. But on these small planes you have plenty of weight budget for a strong sturcture without going to crazy light indoor wood.

You just need a plan to get there. Figure it out ahead of time. Weigh parts as you go. Minimize glue use. Etc.

Jeff Anderson
Livonia, MI

[smartkid222]

I got .63g if you keep the wing chord at 6.5. Mr. Anderson is kinda right. It's not that big of a deal considering that WS planes are so overweight. Keep in mind though that they are much lighter covering materials out here. Looking at my notes PPP film would weigh only 0.03276g on the same size model.......y do i feel that i've typed this before???

[smartkid222]

That's cause i have, it's on the middle of page 4 if anyone want more info on covering.