craschworks

Doodle Bug footlaunched powered hang glider.

The Doodle Bug.

Conceived in January 1999, the Doodle Bug was designed to meet a market opening for a compact supine powered harness that requires no major modifications to an existing hang glider wing. The prototype flew in late February and series production started mid June. Since then the Doodle Bug has become Britain's best selling powered harness proving its benefits over its rivals.
The Bug fits onto almost all modern hang glider wings transforming them into a motorised glider that frees you from the constraints of a hill, winch or aerotow. Once the engine is switched off the performance of the hang glider is little affected thanks to the sleek design of the unit.
The Bug has a spacious stowage area behind the pilot allowing you to store a glider bag, sleeping bag or a light weight tent this; coupled with very easy ground handling (for this type of machine) makes for a realistic bivouac tourer.
Launch is very simple requiring only a few steps in a light breeze and will become airborne in less than 25 meters in calm conditions.
After launch the pilot sits back into the seat and then moves his / her legs forward through the control frame.
The support legs are then retracted by pulling down the overhead foot stirrup to support the pilots feet, this automatically retracts the legs along side the fuselage.
The Doodle Bug / hang glider is a true retractable undercarriage aircraft weighing less than 60 kilos.

Controls are typical to the wing that the Bug is attached to with no adverse affects to the flying controls. The side cords of the unit stop any unwanted lateral movement of the engine which inhibits powered spiral instability (tightening into turns).

Landing the Doodle Bug is probably one of the easiest things about the unit. The pilot releases the foot stirrup which allows the legs to swing back ready for landing. After bringing their feet back behind the control bar they then rotate out of the seat and adopt the upright position commonly known as the “Gorilla Position”.

The bug retractable legs in action

The landing approach is made similar to a normal hang glider, with a little additional speed to allow for the extra weight of the unit. After rotation the unit's legs start to drag on the ground and the pilot gently flares the wing to produce a perfect 2 to 3 step landing. The drag from the legs eliminates the need for an aggressive flare.

Because of the Bugs light construction, 21 kilos, the additional weight compared to a normal harness is minimal (approximately 14 kilos). This means that the sink rate of the wing remains little affected, allowing for engine off soaring. The kick start makes air restarting easy and practical, instilling confidence in the system.
The integral fuel tank keeps things clean and streamlined, and with its 8 litre capacity gives an endurance of 4 hours plus. Thank goodness the Bug has the most comfortable harness for its type.

The Radne Raket (Raket is Swedish for Rocket) 120cc two stroke engine produces 14 HP @ 9000 rpm. Its fuel consumption at full power is 3.5 litres / hour and when throttled back to cruise sips fuel at 2 litres / hour. Thanks to its low weight (6.5 kilos), its exceptional reliability and economy the Raket is the obvious choice.
The Radne drives a fixed 2 blade propeller made from laminated yellow poplar for strength and lightness, fitted with a Polyurethene leading edge as standard.