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 Self-Propelled Hang Glider (SPHG).
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 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.
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The DoodleBug breaking the World
Altitude record for a SPHG. Pilot: Stewart Bond. Wing: Aeros Discus |
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Because of the Bugs light construction, ~25 kilos, the additional weight
compared to a normal harness is minimal. 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, and an electric push-button start is available.
The integral fuel tank keeps things clean and streamlined, and with its 9litre
capacity gives an endurance of 4 hours plus. The supine seating position allows
relaxed long-distance flights in comfort.
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.