Power Slope Scale

F-104 Starfighter by Larry Sorenson

This is a model of the F-104 Starfighter. The full size prototype first flew fifty years ago in March. Here's some spec's for my model:

 

 

 

Length	:	59"
Span	:	44" (long) / 23" (scale)
Area	:	332 sq. in./ 184 sq. in.
Weight:	:	37 oz. / 33 oz.
Loading:	:	16 oz/sq. ft / 26 oz/sq. ft.

Construction is fiberglass/white glue over blue foam. The longer wing is brown paper over blue foam. Paint is latex. Controls are aileron and full flying elevator.

The model flew well in 15-20 mph wind with the long wing. After balancing and trimming with the long wing, I bolted on the short wing and headed for the bungee.

The model was very well behaved with the short wing and seemed to fly much faster. Roll rate was phenomenal! I expect the model to be a quick and responsive flyer in 25-30 mph slope winds. I wasn't sure what to expect with this short-winged model, but after about a dozen bungee flights it seems to fly fine. Looking forward to the next big wind day with the plane.

Bell X-16 by Bert Olson

The Bell X-16 was a featured plane in the Sept 2002 issue of SE Modeler Magazine Vol. 7, No. 7. I searched the web called Bell and worked with the EAA library at Oshkosh to get as much data as I could on the Bell X-16. All the data was similar but very little of the documentation matched. EAA said they had a set of 3 views from one of the Jane's books but they never sent the information even though I sent them the $5.00 they wanted to copy the page.

The Bell X-16 was the loser in the competition that produced the U-2 high altitude spy plane. The Bell X-16 proto type plane was never fully assembled. A fuselage was complete which I found a picture of the wing's trailing edge forward. The wings and jet pods were never completed. I was able to get a picture of the designers mock up model to compare my finished plane to.

I wanted to build the X-16 as close to scale as possible. I took all the data I had and listed the most common listing for:

Wing Span	:	114' 10"
Length	:	60' 10"
Height	:	16' 7"

Then I scanned the 3 view from SE Modeler and scaled that up to full scale in CAD.

I found that none of the view agreed with each other or to the scale dimensions. So I committed to building this plane to the dimensions listed above. The original SE Modeler 3 view's provided angles and some proportioning within each view. I calculated separate scale factors for X and Y in each view then checked each against each other view to come as close to scale as I could make the plane. The only dimension I intentionally changed was I shortened the vertical tail 1 inch in my 1:24 scale (full scale I would have shortened the vertical fin 2 feet). Even with this shortening I did notice that the plane wagged its tail on a couple of higher speed turns (this is a characteristic of an over sized vertical fin on RC models).

The construction started with the wings first. The templates for the Fun 1 club build (SD6060 airfoil) gave me scale tip and root cord within 1/8". I cut the wing plan view from my scale CAD drawing out of pink construction foam. I then hot wire cut the wing cores. These templates were design for 1/16" sheeting. In bagging the wing I added .5 oz/sq.yd. carbon tissue under the balsa to stiffen the wing up.

The tails are a bagged glass over foam core construction. Ed Berris provided me with symmetrical SD8020 compufoil prints to cut the tail surfaces. Again I added .5 oz/sq.yd. carbon under the 2 oz/sq.yd. glass cloth to stiffen the thin surfaces.

The fuselage was the most difficult to build part of this plane. I used the hot wire to cut a round solid pink foam cylinder the length needed for the fuse. I made profile side templates and rough cut and top/bottom and side profiles of the fuse with the hot wire. I then use sanding blocks to finish shaping the fuse. I shaped a canopy separately and glued this to the fuse. Next I hot wire cut the wing seat out of the fuse, again using hot wire technique. See attached photo.

The fuse was than covered with a single ply of 2 oz/sq.yd. fiberglass cloth and epoxied down. The last 1/4 of the fuse was cut off to help hollow out the fuse leaving approximately 3/16" wall. The tail section of the fuse was epoxied back onto the fuse. The wing was fitted and thicken epoxy was use to form a good fit wing seat with small fillets. I put a fiberglass and epoxy doubler on the inside of the fuse through the wing seat area and one to two inches further each direction. A second layer of fiberglass and epoxy was applied to the fuse from the nose to just past the parting line near the tail of the fuse. The fuse was filled with body filler and painted.

The wing tip were formed from solid balsa and routed to fit the wing section.

The servo pockets were cut in the wing and servos installed. Ailerons were cut out of the wing and relieved for the hinge. I decided to use torque tube ailerons and hide the linkage in the jet pods, still using two servos.

Jet pod were built using the same method as the fuse, only using white foam and a single lay-up of fiberglass and epoxy.