Eipper Quicksilver - Design and Development

Design and Development

Founded by Dick Eipper, Eipper Formance began manufacturing the early Bob Lovejoy designed Quicksilver ultralights in the late 1970s when hang gliding was very popular. The Quicksilver hang gliders differed from most hang gliders of that time period in that the Quicksilver had a rigid wing and a tail with a horizontal stabilizer and a rudder. At that time, the majority of the hang gliders were simple Rogallo wing type hang gliders.

Eipper added a seat, wheels, and a small engine behind the wing of the hang glider, and the Quicksilver ultralight was born. This aircraft was controlled by pushing a bar forward and backwards, and side to side, in the same way that hangliders are controlled. This shifted the center of gravity of the aircraft and allowed the pilot to control the plane. Many pilots wanted an aircraft that was controlled with a stick and rudder, similar to the way "typical" light airplanes are controlled, so Eipper added rudder and elevator control surfaces to the Quicksilver ultralight, giving it two axes of control. This aircraft was called the Quicksilver MX. The high dihedral of the wings caused the plane to bank when the aircraft was turned with the rudder, but there was no direct means of controlling the roll axis of the airplane—the aircraft only rolled in response to the yaw axis. Pilots still wanted a true 3-axis control ultralight, so Eipper added spoilers. The spoilers were ineffective, only providing a minimal amount of control over the roll axis. The next generation of MX had true ailerons which gave the aircraft full roll authority.

The single-seat Quicksilver MX not only complies with the US FAR 103 Ultralight Vehicles rules, but was in fact the aircraft around which the rules were developed. The Quicksilver was the most popular ultralight aircraft design when the regulations were first drafted in the early 1980s.

The Quicksilver MX evolved over the years. A two-seat model was added for training purposes, although the two-seater was not legally an ultralight. Eipper Formance changed their name to Eipper Aircraft and then Quicksilver Aircraft, and they are still in business, although they are not producing aircraft in the quantity that they were at the height of the ultralight craze in the mid 1980s.

The current production MX Sport and Sprint are built from anodized aluminum tubing that is fastened together with bolts. The wings and tail are covered with pre-sewn Dacron envelopes. Reported construction times from the kit are 30-40 hours.