History of the pioneer

When the PIONEER series sailplanes was first conceived about 40 years ago, we wanted to design and build a homebuilt that would be simple, high performance and constructed at a reasonable cost. We wanted a sailplane that truly was a fun to build and fly aircraft. One that would spend the greatest time in the air with a minimum amount of effort and expense to keep it there; What was needed was a sailplane that would stay aloft in marginal conditions even with a novice at the controls. A sailplane that would inspire confidence in the pilot through it's lack of bad flying habits. It's performance must be great enough, in glide and penetration, to be capable of excellent cross-country abilities and badge flying. It must have outstanding auto towing characteristics for flying where airplane towing facilities are not available. Last but not least, we looked for home construction in a standard sized garage.

Our first attempt at designing the ideal sport sailplane was thePIONEER I. It was a flying wing version of the Schweizer 1-26.The wingspan was the same at 40 feet. Wing area was 180 squarefeet, or the combined wing and horizontal tail area of the 1-26.Even the airfoils were similar. We used an NACA 33012 with reflexed trailing edge instead of the NACA 43012A. Empty weight of the two aircraft were about the same at 450 pounds. Performance of the two sailplanes were about the same at low speeds. However, above 55 mph the Pioneer clearly had the advantage in penetration. Ilts handling and stability characteristics were outstanding. Two things we didn't like about the PIONEER I was the length of time required to build it and it's high empty weight.

Pilots who were qualified, and had the courage to fly such an unusual sailplane, became as excited over the PIONEER as we were. This response, along with the many inquires we received, encouraged the development of a second design which we were to call the PIONEER II. This sailplane was lighter, easier to build, and aerodynamically cleaner than the PIONEER I. As a homebuilders project it is simple and quick to construct utilizing as few parts as practical. All too often a builder gets discouraged by his slow rate of progress, confused by the complexity of parts, and loses interest in the project. So in this design, we made a special effort to keep the design clean and simple.

Since this is a flying wing, or tailless design, handling characteristics in the air and on the ground can be, and are, different than it's tailled counterpart. First off, it is lighter and more compact, a great asset in storage and rigging. Due to the short fuselage and main-wheel location, just behind the aircrafts c.g., ground looping or cross winds have not been a problem. In the air all controls are conventional and give the pilot a familiar feel.

To mentally visualize the wings stability, picture a wing with it's center of gravity very near the leading edge. Such a wing,so balanced, reacts similarly to that of a weather vane relative to an airstream. A bend, or curve, near the trailing edge provides a degreeof positive or negative pitch. A most important benefit of the weathervane affect is the fast response to vertical accelerations experienced when flying at near red line speeds. The wing will automatically adjust itself to the new angle of attack instantly thereby reducing vertical accelerations due to turbulence.

One of the most exciting discoveries while flying the PIONEER early in the test program was its inability to stall.Even with the control stick back against the stop there is no break - the nose will not drop. Rudder and ailerons remain responsive, even in tight thermaling turns. Furthermore, if the aircraft is within the prescribed c.g. limits, the PIONEER will not spin.

The PIONEER's large 6011 root chord allows for a larger c.g. movement which minimizing the need to counter ballast the aircraft due to varing weight pilots. Additionally, the pilot is seated very near the aircraft's c.g. resulting in only minor changes in c.g. movement.

The cockpit of the PIONEER II sports a molded fiberglass semi-reclining bucket seat for maximum pilot comfort. The pilot's weight is evenly distributed over the entire length of the seat making a long flight less tiring. Big, tall pilots will be happy to know that the cockpit is 24" wide and can seat a pilot well over six foot tall. Maximum pilot weight with chute is 250 pounds.

Rigging the aircraft is similar to that of many conventional sailplanes. Two taper pins, per wing, secure the main spar to the fuselage center section. The rear spar is anchored with a quick release pin. All pins are inserted within the fuselage so that no exterior access, doors are necessary. Elevator torque fittings are automatically coupled when the wing is joined to the fuselage. Aileron and airbrake runs require a pin to be inserted and fastened.

On the prototype, we experimented with both a nose hook and center of gravity hooks. The nose hook proved to be rather limited in its use. Freedom of movement was restricted in pitch, particularly on winch or auto tow. Ground towing with c.g. hooks, located a few inches back under the leading edge of each wing on the fuselage sides, provided very smooth takeoffs and gave complete freedom of movement. Very high altitude auto tows were obtained using the c.g. hooks.

One would suspect that such a short coupled aircraft would be overly sensitive in pitch. We have rigged the control system so that it requires a lot of stick input to move the elevators a small amount. As a result, the pitch rotation speed is reduced to that of a conventional tailed aircraft.

Pioneer Kits
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