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2002 1 liepos @ 13:49 #148552martynas
Radau idomu Airwave pareiskima, jog ju naujas sparniukas pasieke si magiskaji kokybes barjera!
25th Jun 2002
Confirmed glide of 10.2 on the Ten at trim speed
The idea behind the ten is to produce a competition glider with best glide of 10 to 1 that is easy to fly. For many months now we have been trying to measure the glide performance of the different prototypes. This performance testing has been made mainly in relation to the Magic, whose glide performance has been well established at 8.6 from tests by Noel Bertrand at Vol Libre magazine. We made glide tests on many different days against several different control gliders. This relative testing is done by gliding next to the other glider with the same harness and pilot weight (both mediums), tip to tip, and then measuring the height difference between the two gliders after one minute. From this difference in sink rate at trim speed it is easy to calculate the glide difference at trim speed. These tests have consistently showed glides figures of just over 10.
However we did not want to release the glide performance figure for the Ten until we had done an absolute and precise glide measurement, not a relative measurement as described above. The main problem with absolute glide measurements is accurate speed measurement (this problem is neatly avoided by two gliders flying at the same speed). Adrian calibrated our speed probes in his wind tunnel but they typically had errors in excess of 5% – one read 55 when you were actually doing 60kmh). Another problem was drift – the speed probe calibration changed from day to day (due to dirt in the mechanisms, alignment problems, altitude, humidity and temperature effects). Seeing as current competition gliders already glide at 9.5, we are looking for a 5% improvement in glide to get to a glide figure of 10. Using speed probes to make measurements of the accuracy we needed was therefore out of the question. We decided the only really accurate method was to wait for completely calm conditions, and use a GPS logger. It was also necessary to check from the track log data tto confirm that there really was no wind at all. We made two previous attempts at absolute glide measurement but both tests had been spoilt by finding wind interference during the analysis of the track log.
Last night just after sundown Bruce had perfect testing conditions in Greolieres. The pressure has been high all week and the air was very still and stable with no wind. The windsocks on take-off and landing had not moved for an hour, and it was getting dark. Bruce used a Sol 17 logger linked with a Garmin12map, and we analysed the results with Compegps and Excel spreadsheets.
Glider: Airwave 10 medium with microlines.
Pilot: Bruce Goldsmith with X rated harness.
Total flying weight: 102.5kg
Temperature: 25degrees C at take-off, 22 degrees C at landing (very inverted!)
Take-off altitude: 900 m
Landing altitude: 450 m
Pressure at Sea level: 1016 mb
Trim speed: 38.8 km/h gps
Trim speed glide: 10.2
Most of the tests were made at trim speed so we are confident of the measured trim speed glide of 10.2. Further detailed analysis of our data produced a polar curve for the 10 between 25 and 45 km/h. This polar curve actually shows a best glide of 10.6 at 42km/h. We will need to do further testing and measurements to verify this, but it looks promising to say the least!
We are finally delighted to confirm that the 10 does in fact achieve a best glide of more than 10:1. This is surely a milestone in paragliding.
Ten dar ir grafikelis yra, jai kam idomu:
Teisybe tai ar ne – laikas parodys. Bet kad ne uz kalnu tas laikas tai tikrai2002 1 liepos @ 19:11 #155680Anonimas
tai chia jau ne naujiena,
tas aparatas jauchiu skrenda kaip mechio prototipas, kas ish tokios kokybes jei jos nepanaudosi. Priedo tokia kokybe pasiekiama tik su x-rated.
kle2002 4 liepos @ 19:07 #155690Anonimas
graziai atrodo tyeorija.Tebunie siam sparnui Panevezio dangus – tada ir nuspresime,ar jis to vertas…
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