WORLD ALTITUDE RECORD

Building the kites

The kites we use are a type of hybrid kite, combining the efficient lift of a delta and the stability of a cellular kite to form what is know as a Dunton-Taylor Delta. This kite was developed in the 90’s by Charlie Dunton in the USA and a modded version by Hod Taylor who was known for his very large kites of this type. It’s origin was in a variant of the Conyne Delta or French Military Kite called a full-cell Conyne Delta but has a cell cutout at the top and scalloped wingtips. The reason for it’s selection for high altitude flying is it’s power, high flying angle, wide wind range, strength and stability. It has a reputation of being a very fast climber and is chosen for fast climbing competitions, that is, time to altitude. I have GPS data which shows my big DT Delta kites can climb as fast as 1,000 ft in 30 seconds. These kites have very benign behavior when the wind falls below the lift threshold. They backdown very gently rather than losing altitude rapidly between wind gusts.

There are other kites which may be suitable under certain conditions. These include:

Hargraves Box Kite - requires more wind and flys at a lower angle but develops more line tension and is is very stable.

Delta - suit lighter winds, not as stiff as the DT Delta and lighter but will ride thermals and light winds at a higher angle. Tend to become unstable in winds over about 15 knots.

Parafoil - Tremendous lift and develops high line tension at high flying angles. Requires steady winds and can lose inflation in light winds with thermals and turbulent conditions. Loss of inflation may not be recoverable.

Winged Box kite - less compact than DT Delta and  heavier for given surface area. Is more complex to build and has more parts to assemble on field. Has not proven superior to DT Delta in practice but in theory should have greater lift to weight ratio.