Z Gee Bee Z Gee Bee Z
1/5th scale Gee Bee Z

Designed by Adrian Page
Featured as a construction article in the August
1998 issue of R/C Modeler Magazine

	Specifications: Span = 57" Length = 34" Weight = 5 1/2  to 6 lbs. Wing Area = 550 sq. in. (24 oz./sq. ft.) Engine = .46  2 Stroke to .56  4 Stroke Kit price: $159.95
This is what is included in the Gee Bee Z kit. Fiberglass cowl Laser cut balsa and ply parts Black line rolled plan  Pre bent landing gear Top quality hardware Vac-formed ABS plastic parts Full color mylar decal sheet Illustrated instruction manual Click here to download the manual as a PDF
	This is my own Gee Bee Z . It is covered in yellow Aerospan film from Balsa USA. The black is painted on with 21st Century spray paint. The flying wires are elastic cord thread from a fabric shop. They are attached to little hooks embedded in the wing. The rigging simply unhooks from the fuselage to allow the wing to be removed. This plane was built with the ABS wheel pants.
These are the optional fiberglass wheel pants by Aeroglass. As you can see they are pre joined and ready to paint. The pants are $45.00
	This radial engine kit really dresses up the nose of the plane. It is intended for use in flight. The radial kit is $12.00

This model is the result of years of painstaking research. Although this is a sport scale model the outlines are very accurate and were taken from actual photographs of the full scale plane. Details like the correct number and spacing of the fuselage stringers has been used. The model has been simplified in two areas for quick construction; the wing incorporates strip ailerons and the wing fillets have been modified to allow easier building. The correct scale details of these areas are shown on the plan if you wish to build your plane to accurate scale detail. The plan also shows the correct placement of all numbers and decals, as well as many other scale details.

Flight performance is excellent. Top speed with the Saito .56 4 stroke  is approximately 70 mph. The problem faced by anyone who designs a Gee Bee is how to build the thing light enough for good slow speed performance. My design is much lighter than any other Gee Bee I have been able to find. Note the 24 oz. wing loading. As a result the slow speed performance is unlike any account of model Gee Bee flying I have read about. High speed performance is very smooth and hands off stable! Slow speed flight performance is gentle and predictable. The plane does not stall and recover...it just "mushes". Because the wing incorporates washout, it will not tip stall. Knife edge is accomplished with no aileron correction and very little rudder input. Roll rate is very realistic at the recommended throws. Landing requires a long low approach - and a three point touch down. I recommend test flying the plane on a day with a good breeze blowing down the runway. This will reduce the ground speed, "lengthen" the runway, and keep good airflow over the tail.

Most people think Gee Bees will be difficult to fly because they are short coupled. Nobody seems to worry about flying wing models though. Flying wings are so short coupled that they have no horizontal stabs at all! Actually Gee Bees are not as short coupled as people think. The "fat" fuselage gives the illusion of a short tail moment. They are very close in plan form to the Sukhois.

Engine:

As mentioned earlier I wanted a Gee Bee that would perform well on a .46 2-stroke, but I used the new Saito .56 4-stroke in mine and it turns an APC 11 x 6 prop at 11,500 rpm. While I did not actually install a .46 2-stroke in the model, I did take tach readings of several such engines at the field. The most impressive reading I took was a Magnum .46 with a Tatone Pitts muffler - 12,700 rpm on the same prop.

Take off:

Feed the power in slowly and hold a touch of right rudder and up elevator. Do not try to run up on the mains; the engine's thrust tries to pull the nose down and you will probably do a high speed flip. Take off in a "3 point " attitude and you will never have this problem.

Low speed flight:

Contrary to popular belief, this is an  aerodynamically sound design. Stall tests of the prototype show it to be almost stall proof. It just does a right hand circle, and doesn't sink much while it is doing it.You might want to read the specs again - what we have here is a floater. One small "bug" I have found is thrust will pull the nose down if you throttle up suddenly at minimum airspeed, as in a "go around."

High speed flight:

With the Saito .56 it goes about 85 mph and is a smooth a silk. Vertical is very good. If you put it in a banked turn, it will stay there longer than any plane I have ever flown. It is extremely neutral. There is no twitchyness of any kind - a very realistic performer.

Aerobatics:

On the very first flight I did a huge loop, axial rolls, knife-edge, a stall turn, and a split s. Ailerons are a bit tame at the throws indicated - about one roll in 1.5 seconds, but if you want to change direction, it will bank and yank with amazing speed! ( It is, after all, a pylon racer.) No aileron correction is required for knife-edge flight.

Landing:

With 550 square inches of wing area and a weight of 5 lbs 13 oz. you will have a very low sink rate. I found it a challenge not to overshoot the runway in zero wind conditions. Speed does not bleed off in a hurry. This plane lands long, low and flat. I always land in a 3 point attitude. I have been unable to grease it in on the mains. Maybe it could be done on pavement.