Further to our first attempts at fully automated formation flying (see http://diydrones.com/profiles/blogs/ardupilot-formation-flying-attempt), Phil (http://diydrones.com/profile/PhilRudram) with his rebuilt Valdez (v2) and I headed out to try again.
Most of the flights were really good with the two planes following the route (and each other) very well. The turns especially were almost mirror images of each other and watching the two planes from the ground flying in almost perfect formation was amazing.
The first afternoon was really calm and this benefited both planes a lot. Each flight lasted around 25 minutes.
On the first day we tried a triangular course with waypoints around 700m (2300ft) apart but on the second day the course was set rectangular with the long legs around 1200m (3930ft) apart. The wind however had picked up a bit and was a bit lumpy with thermals starting to build.
We took about 2 hours of onboard video with a Mobius camera and a bit of ground video, but due to the wide-ish angle of the Mobius' lens the lead plane was often quite small although they looked really close at times both from the ground and from the FPV video setup on my plane.
All went very well until... not unexpectedly - a midair collision!
See the video for details.