Below is a copy of an email message sent to DJI In Re: Inspire 1 Fly Away on July 13, 2015
Between the initial flight(s) on July 11, 2015 and the fly-away date on July 13, 2015, the Inspire 1 had flown approx. 30 flights, logged under two different users. All flights were flown using dual remotes. Most of the flights were flown on July 11 and July 12, prior to updating to the latest firmware. The UAV’s compass was always calibrated before flying. All of these flights averaged approx. 11 minutes and were all without incident. We tested all system functions including auto take-off and landing and emergency RTH functions and the craft always responded as expected. All flights have been flown in P-GPS mode.
The firmware for the craft and controllers was updated between flights on July 12 and July 13. We started flying around 2100 CST on July 13 and a total of three flights were flown, including the fly-away. The first flight was without incident and the battery in the craft was replaced with a fully charged battery.
According to flight logs, the second flight was initiated at 2113 CST with a duration of 7:22, maximum height of 263 feet and a flight distance of 10,216 feet and the auto take-off function was used. Approx. 2:50 into the flight, a RTH command was sent to the aircraft after losing visual contact with the aircraft. Radio/Video communications were also malfunctioning and we noticed that the craft seems to be flying on a tilt, rather than level. The craft began it’s return to home and around 5:45 flight time, visual contact with the craft was resumed. The craft automatically initiated the landing gear and started decending above the home point. At an altitude of 92 ft., I cancelled the auto landing and manually landed the craft without incident. The craft was inspected and everything looked as it should including all of the props being securely attached.
At 2121, the craft once again took off using the assisted take-off. After the issues on the previous flight, we were cautious and wanted to do a test flight, staying roughly within a 100ft radius of the home point. At approx. 2:40 into the flight, the controls seemed to have become unresponsive. The craft was above the home point and we had a full visual (eyes and video) on the craft. I released all controls and then noticed that the craft started to drift. I tried regaining control of the craft but all communications seemed to be down at this point. No controller input was registered by the craft and it had become completely unresponsive to any input. At 2:57 a RTH command was initiated. We still had full visual on the craft which was at an altitude of 108 feet and 126 feet south of the home point. The craft ignored the RTH command and looped around to the west past the home point. Manually trying to over ride the RTH command and regain control of the craft was unsuccessful and no communications were registered between the controller and the craft. The craft took off to the NE and made another circle, one block to the east of the home point. The craft moved back to the west and appeared to be coming towards the home point. It then turned back to the NW and a command to resend the home point location was sent to the craft at approx. 3:34. The craft once again ignored the command to RTH and was unresponsive to pilot input. The craft continued to the N and then turned to the NE at a horizontal speed between 50-60 mph. We had lost visual contact at this point, including video. The last recorded point was 1,966 ft to the NE of the home point with an altitude of 249 feet and a horizontal speed of 57 mph with 13% battery remaining. A full search of the area within about a 1.5 mile radius of the last known location turned up no results and the craft has still not been recovered. |