Mac-

Hi Guys,

I have just completed my own design scratch built foam delta model. It has a 36inch wingpan and with an OS .35 FP has a total weight of just 2 lbs.
I Know that the general rule of thumb is approx. 1lb of model to 1cc of power.

Although the OS.35 is not a particularly powerful engine can anyone advise if it will be too powerful for my delta.
The model is merely a shaped sheet of polysterene which has been covered with thinned pva glue in brown parcel paper then fibreglassed with .6oz glass cloth.
Wing loading is approx. 15 ozs per sq/ft.

Thanks in advance.

Mike James

That's plenty of power. (depending of course on what you want to do with the plane)

Typical power loadings for sport models are quite a bit higher, if you think about a 5 pound model being powered by a .40 to .46, for example. (I created a page that shows some of these power loadings, at http://www.nextcraft.com/aircraftdesignconcepts.html It uses "cubic inches" rather then "cubic centimeters" )

Cool, simple design. Let us know how it goes.

Mac-

Thanks, Mike.

CrazyHerb

My Feedback: (1)

I've done several foamie deltas... www.crazyherb.com
Your .35 is fine for that size....you'll have gobs of extra power...and the extra weight of a slightly larger engine helps with the CG.

One word of caution if I may ...
You should trim the outboard tips of your elevons....Delta's create some knarly tip vortexes...those elevons hanging out in the vortexes are gonna create some erratic flight behaviors...

Good Luck! Looks GREAT!

CrazyHerb

Mac-

And you're right. I've now fitted the .35 2-stroke and the model balances out perfectly. A lighter engine would have needed lead in the nose.