From the time I pre-ordered my Solo drone from 3D Robotics on their launch announcement day I’ve been excited to test their claims of being able to get incredible cinematic shots with one operator. If all the hype about the “first smart drone” is true then this is going to be an evolutionary leap forward for aerial cinematographers and independent film makers. By the time I finally received my Solo, I had plenty of time to watch all the orientation videos and read all the documentation I could find online. So, along with several years of flying other multirotor platforms, I thought I was well prepared to take it out for its initial test flight. After making sure that the batteries for the controller and Solo were completely charged and all the firmware was up to date I took it to friend’s house for it’s inaugural flight (his backyard is much bigger than mine and I wanted the first flight to be in a large open space).
After powering on the controller and Solo it seemed to take a long time to get a good GPS lock and declare itself “ready to fly”, but it was ready soon enough and I pressed the FLY button to start the motors. Pressing and holding the FLY button again launched the Solo into the air and I gave it a little thrust to raise it to about 8 feet off the ground and let it settle in to see how stable it flew. It was rock solid. It was so steady it almost looked like an optical illusion where the Solo was sitting on an invisible shelf because it wasn’t moving at all. I was thoroughly impressed.
As with every flight, I performed a basic test of all the movement controls to ensure everything was reacting correctly. I tentatively used the sticks to try the pitch, roll, yaw, and finally a little thrust to see how it handled at a slightly higher altitude. That’s when things started to go wrong. Once the Solo climbed to about 30 feet it started to act erratically by flying aggressively forward into the wind then backward without me touching the controls. I immediately tried to counter the Solo’s movements by giving it the opposite commands so it wouldn’t collide with the house. After a few tense seconds I was able to bring it back under control. At that point, I thought that the wind at the higher altitude might be causing problems so I navigated it back to the center of the backyard and started to slowly bring it back down.
Unfortunately, the Solo started accelerating as it came down (I made sure to bring it down at an incline instead of straight down to avoid creating a vortex ring state) so I quickly let go of the left stick hoping that it would level out and hover. That wasn’t the case. Even though I was no longer pulling the left stick down Solo was still heading for the ground; quickly. At the last minute I tried to push the left stick up to keep it from hitting hard, but it still touched down on uneven ground and flipped forward onto it’s back.
Here’s where things got interesting. Based on my previous experience with 3DR and other drone manufacturers I made the assumption that the motors would stop trying to spin once it was clear there was an obstruction preventing operation. In my mind, this is a core safety feature that should be a part of every RC flying system. When I reached down and attempted to right my turtled Solo the blades sprung to life and started spinning at full speed almost catching my arm. I quickly set the drone back down in the grass upside down so that no one would get hurt and tried using the controller to stop the motors. At this point the controller seemed to believe that the Solo was still in flight so I tried pressing and holding the FLY button a couple of times to instruct the Solo to “land”, but I could still hear the motors trying to spin so that didn’t do anything. I finally gave up and turned the controller completely off and that did the trick – the motors stopped and I was able to pick up the Solo safely.
At this point I thought I was going to be able to turn the controller back on and get back into the air in a few minutes. I put the Solo back on it’s feet and made sure that the controller had reestablished a good connection and said that the Solo was ready to fly. This time when I pressed the FLY button to start the motors spinning only three out of the four started up while the fourth one moved with a slight nervous twitch. Seeing there was a problem I wanted to stop the launch sequence and investigate, but not knowing the command to stop the blades from spinning I accidentally pressed the FLY button again (in my mind pressing and holding the FLY button was intended to be a “land” command, but obviously that’s not right). With only three blades spinning the Solo attempted to take off and just flopped forward onto it’s back again so I killed the power to the controller and turned off the Solo. Now, when I try to turn on the Solo the number three motor makes a slight knock sound and the blade twitches slightly then quietly turns itself off. Bricked. 🙁
So, after a total flight time of under five minutes my Solo is now completely unresponsive. I’ve submitted a support ticket with the flight logs attached and have already received an automated reply stating that they are “experiencing a high volume of tickets at this time” and that someone will get back to me in 1-3 days. I hope that they come to the same conclusions that I have:
- I was not in complete control of the Solo during about 10% of the flight
- The Solo kept descending toward the ground even after I released the left stick
- There should be a safety cut off for the motors if the blades are obstructed
- The motors were extremely hot after trying to spin in the grass
- I assume that’s what fried one of the ESCs
- There should be a more intuitive way to cut the motors in case of an emergency (after reading the manual again I now know you have to press and hold the A, B, and PAUSE buttons)
Now it is in 3D Robotic’s hands and I get a chance to evaluate their support process. To be honest, it was really easy to submit a trouble ticket with the flight logs attached so at least they’ve got that going for them.