We're gearing up for the final avionics test flight of the Low Orbit Helium Assisted Navigator (LOHAN) project, and have dubbed the mission PRATCHETT ("Planes Reactive Airborne Tests Checking Heuristically for Extreme Technological Tantrums") in honour of the late Discworld author Sir Terry.
In October last year, our US allies at Edge Research Laboratory sent a rig comprising Pixhawk, servos and batteries - identical to that mounted in our Vulture 2 spaceplane - up to 27,700, to see how the whole thing would handle the cold.
Autopilot brain surgeons Linus Penzlien and Andrew Tridgell picked over the results and suggested a few modifications, including sticking a Zener diode across the servo power rail and activating better battery monitoring. The full findings are here.
So, we reassembled the kit and it's good to go stratowards in the next couple of weeks. On board will also be our 900Mhz radio rig, by which Tridge can monitor the Pixhawk's status in real time. Try this schematic of the full rig, and a photo of how that looks in the PRATCHETT payload box:
There are full details on PRATCHETT flight right here.