Ava High Altitude Balloon Project

Although the new pAVA R9 board flew successfully on our glider record attempt (Here : http://ava.upuaut.net/?p=650) I decided it would be best to actually launch it under a balloon. With quite a bit of help (i.e he re-wrote it) from Phil Heron the code for the DominoEX was modified to transmit THOR16 (DominoEX extension with FEC, by Dave W1HKJ). I believe this is the first balloon to use it.

Error corrected telemetry plus the extremely stable radio should make for an easy payload to track. The weather hasn’t been exactly pico friendly recently but the winds looked great, fast and taking a swing by Poland (later turned out not to be the case). So I soldered some antennas on, a battery and wrapped the lot in “space insulation” (foam bag, Kitkat wrapper foil and Kapton tape) :

I left the battery disconnected until just before launch. The tracker came in at 12.4g all in which is my lightest by far :

The weather on Saturday was very changeable. Initially I called the launch off but around lunch time the clouds cleared although the wind didn’t subside.The predicted path looked too good to waste so I took chance. With 1.5g of free lift the 36″ Qualatex balloon didn’t look inflated at all.

The battery was soldered on and attached to the balloon, the lot was thrown in the car and I drove up to my launch location close to home. It was extremely windy up there and the balloon was getting whacked about, rather than hold on to it I decided to just let it go and hope for the best.

Initially it rose up but then seemed to hold at an altitude, shortly afterwards I lost it visually jumped back in the car and drove home.

It was only when I got home I noticed just after launch it had dropped back down, possibly landed in a field, taken off again and missed the electricity pylons by meters :

I seem to be getting quite good at the “unintentionally sketchy launch”. The balloons ascent was interesting to say the least but up was up even if it did contain small amounts of down on the way.

And off it went climbing up to about 7km where it entered a lovely float, the speed peaked at 175kmph (just over 100mph) as it sped towards Europe. Floating through the night over Germany I woke up on Sunday morning to find it had been tracked almost continuously through the night and was in Romania. Fortunately we managed to muster enough trackers to follow it all the way to the Ukraine where it was tracked by UR6ISU and UY0LL and as it entered southern Russia. Finally around 14:59UTC on Sunday the battery finally died at 7.5km just after entering Russia reporting a final battery voltage of 776mV, 8 satellites and situation normal. I have no reason to believe the balloon didn’t carry on through the night.

So covering an impressive greater circle distance of 2900km (3rd in the records) and averaging over 100kmph in 26 hours one could call this a successful test!

Battery data, speed and attitude over the flight (Thanks to x-f for this)

As ever a huge thank you to all the regulars who take the time to track and  to the amateurs who responded to our calls for help on various forums and took the time to help out. It really is a great community.