Pilot Error. From 3DR following a review of her logs..
At 3DR we try to learn something from every flight—the good, the bad and the ugly—which is exactly why we made it quick and easy to submit your flight logs through the Solo app. We got our hands on the logs from this flight as soon as we could and turned our flight analysis machines on the demo. Here’s what we learned: 1. We’re all human. The fight logs show that the crash was unambiguously a result of pilot error. There’s lots of data below for those of you who love a good flight log.2. Flying nose-in is tricky. Before the crash, Solo was executing “Selfie,” one of its automatic Smart Shots. In Selfie, Solo faces the pilot. This is called flying “nose in” and is the mirror-image orientation of typical flight. As a result, the stick controls become inverted: Your left is Solo’s right. (Exactly the same as “stage left” being the audience’s right.) When the Selfie was completed, the pilot appropriately put Solo back into “Fly” mode to regain manual control. Likely in an attempt to get a little farther away from the taco truck, the pilot applied a small amount of “right stick” (figure 1 in the log image below), but since Solo was “nose in” it simply went to its right instead of the pilot's right. Seeing Solo go what appeared to be the wrong way, the pilot applied “full right stick” to try and correct. Unfortunately Solo did exactly that and flew “right” into the taco truck. If you’re a beginner pilot, it’s always a good idea to fly Solo “tail in” as much as possible—which is exactly what Smart Shots allow you to do. So in general, right after a Selfie it’s a good idea to rotate the copter back around until the rear of the copter is facing you, and you and Solo are looking the same way.