Does anyone have an experience with 1/2A ducted fan jets?

I've started a kit that should be fun with a little bit of experimentation and imagination, and still at the point where I'm not really sure what kind of luck I am going to have getting it to fly.

There are many appealing aspects of the kit. It is a 25" Douglas F4D-1 Skyray that uses the traditional Stick & Tissue building methods. There is less than 20 dollars involved with the balsa, glue and covering. Its small size allows it to be carried in the trunk of the car, and the support equipment and fuel cost is minimal.

The plans state a 11oz Free-Flight weight with 250 sq in of wing area, but with carefull building and the weight of the newer micro-system radios of today, no more than three ounces need to be added to it to make it fully proportional. At a predicted 14 ounce flying weight, which is on the light side for 1/2A's, the delta should fly and handle well. The elevator mixing and fully symetrical wing profile with no dihiedral should make it a fast flyer also.

Since there is no currently available 1/2A DF kits to swap parts with, I am finding it difficult to find an impeller that would be suitable for it. Luck has been with me though, finding a couple of out-of-production Veron plastic impellers that have the same diameter as the original aluminum blade, but it has more blades and higher pitch.

This has me concerned about the ability of the Cox TD .049 (LH) to turn it at the proper rpm, but at this point it is about my only choice of impeller. If the blade doesn't work well with the ship, I will be forced trying to convert an electric blade to gas and starting over from there.

With this post, I am hoping others have had experience with 1/2A power, impellers and design to help direct me through the project. Designing or building ideas from others would be fantastic!

I'm hoping others will find this project interesting and show thier support in 1/2A ducted fans! The small expense and fun building can't be beat at this point for me Getting one to fly will be just icing on the cake!