Dyneema®, the world’s strongest fiber™
WORLD ALTITUDE RECORD

 

March/APRIL 2010 10,681 ft!

This years attempt promised much but delivered below expectations. Expected result? World record of 15,000 ft+. We doubled the time period from 7 to 15 days hoping this would double oor chances of encountering good winds. However, it wasn’t from lack of trying nor from any deficiencies in equipment or techniques. There was simple not enough wind. The effort required to reach the great height we achieved, was draining, well, at least for me, Bob Moore! The 35 degree heat, little wind, clouds of flies and plague locusts all conspired to sap energy and patience. Despite these conditions it was an adventure and an endurance challenge. We did achieve our personal best altitude and we reset the Australian record at 10,681 ft above ground level. It was the 2nd highest single kite flight in the world. This was very gratifying considering the conditions presented little opportunity for high altitude flights.

Right: Semi arid land is not as lush as this image suggests. In March/April 2010 much of western NSW was in the midst of a locust plague. There was good rain in the preceding 12 months but this was quicky soaked up by the thirsty soil. 33-35 degrees C in Mid Autumn. This is not an easy country to farm sheep nor to fly kites to high altitude in although I’d much rather be out here than in Sydney. Out of view, the kite is flying at 800 ft at 70 degrees. You may just see the pink line coming off the pulley at the upper rear of the trailer.

Above: The winch worked well with only the line laying control switch needing minor modification. The pink line has stretched, compacted and faded slightly under tension and exposure to strong sunlight. The compaction of the line is good as the diameter under tension has reduced by about 10%. All 6,020 meters of the pink line pluse 555 meters of the underlaying white line was released during the 10,681 ft flight. The pink line is 186 lb breaking strain and 0.63 mm thick as measured under tension. The white line is 292 lb breaking strain and 0.9 mm thick untensioned. Thinner line is used for the top half to minimise aerodynamic drag. Stronger, thicker line is needed for the bottom half as aerodynamic line drag accumulates directly in proportion to the line released. The tension on the line at the kite is just the result of the pressure of the wind on the kite. The tension on the line at the winch is the sum of the resultant of the kite lift and drag plus the accumulated line drag. I estimate that the line drag may be as much as 60% of the kite’s contribution to line tension.

This is the GPS Team software altitude gauge display. It appears on the laptop screen as part of a group of dashboard simulated displays of GPS data in real time.

Flight record from Garmin Geko GPS onboard a 120 sq ft DT Delta, 23/03/10. Flight duration 4 hours with kite dropping into the bush 1.7 km to the north of the launch point. The wind dropped suddenly at all altitudes up to 5,000 ft leaving the kite stranded. Running the winch at full speed failed to maintain flight due to the hot, low density air. The sudden drop can be seen on the right of the graph as the kite decends rapidly. Recovery took several hours and no further high altitude flights could be attempted on that day.5,800 ft reached.

Left: Vertical profile on 30/03/2010. This is typical of a flight at Cable Downs in hot conditions with variable winds. The pattern of sharp climbs and falls indicates the variability of the wind speed and our efforts to release line and achieve higher altitudes. This represents several hours of concentrated  effort but ulimately to no avail. Just 1100 ft above ground level.