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Page 78
Student Experiment Documentation
Picture 14: Recorded airplane tracks during the flight.
Before launch, outside temperatures were at approx. 0°C and a thermal
steady state was reached before launch at 08:49 UTC. While ascending, the
temperatures outside dropped to -40°C quite fast, caused by the cooler air in
higher altitudes. Interestingly, the temperatures began to rise again approx. 1
hour after launch. This was most probably caused by the increasing solar
radiation experienced. In the late float phases we reached equilibrium
temperatures of little below 0°C on the case outside and ~20°C inside the
experiment. All measured temperatures are well within operating conditions.
To be honest, we did not take solar loads into consideration when making
thermal approximations, as none of the former BEXUS flights we looked into
had sun-exposed experiments. From our experience, solar heat radiation can
clearly be taken into account for thermal design of a BEXUS experiment when
conducting a day flight. Luckily, we developed our experiment to withstand
both day- and night-flight conditions, so were not affected in problematic
ways.
7.5
Lessons Learned
7.5.1 Antenna
The antenna was the part that caused the most severe trouble.
BX18_ARCA_SED_v5-0_12JAN15.docx