Back to field testing on January 13-24,2002


A series of test flights were carried out by Lucian Banitz at the Flying Field south of Pretoria on February 27, 2002. Some selected figures generated from these flights are shown and discussed here,

Fig 01: Plot of pressure (MB times 10) versus time (seconds, vertical line every minute) for the second flight on Feb 27th. Note problems during descent.

Fig. 02: Same as Fig 01 except for flight 3 - the highest altitude flight. Note that the ascent rate appears to be slowing down at the top of the sounding - but the powersonde appears to be well short of its maximum altitude. Time to make this sounding (to about 8800 ft/~2700m above the surface) was ~ 16 minutes.

Fig. 03

Fig. 04

Figs. 03-05: Closer views of the pressure versus time trace during the third flight, showing a problem with the pitch control (?) during the ascent.

Fig. 05

Fig. 06

Fig. 07

Figs. 06 - 09: Sequence of 4 successive flights: the plots show the temperature versus pressure traces for both the ascent and descent soundings. The second flight shows a major difference between ascent and descent. The other flights show very little difference. We are investigating the reason… In Fig 07 one profile is in red, the other in blue.

Fig. 08

Fig. 09

Fig. 10: A plot of the relative humidity during the third flight, one color shows the ascent, the other color the descent data. Good agreement!

Fig 11: This figures shows the highest sounding, with both temperature and humidity plotted for both the ascent and descent profiles. Very good agreement overall! Note the temperature inversion near 715 mb (7150 on the vertical axis) and the drop of RH (from 95% to less than 80%) associated with this feature.

Fig 12. Same as Fig 11 except with smaller dots to distinguish better between the temperature curves.