Well, this is awkward.

The launch occurred nearly two months ago! I completely forgot to write about it! So many things in mind...

So, the rocket was launched on august 28, with a perfect weather. The engine ignited as it should, and the rocket flew straight as an arrow. After apogee the D12-5 engine fired the ejection charge. However, I didn't put enough wadding, and the parachute melted a bit, resulting in a mess of plastic of wires instead of the nice deployment I expected. Nevertheless, it slowed the rocket enough, and the rocket landed without any damage. The upper half landed nose first and got stuck in the ground.

The logger worked as planned: it didn't trigger until launch, and the beacon activated 30s after takeoff.

Data recovered from the MicroSD card got processed in an Excel file. Vertical acceleration and altitude were plotted in a time-based graph.

We can clearly see the initial acceleration provided by the engine, and the engine burnout, at which point the altitude rise slowed down. The two peaks we can see afterwards come from the parachute deployment and final landing. I was able to calculate a speed of 244 km/h at takeoff, and a descend speed of 42 km/h, which can be explained by the failed parachute deployment.

For those interested, the spreadsheet containing calculations and the graph is available here.