Confidential Human Factors
Incident Reporting Programme
The Charity
Aviation
Maritime
DUAS XX29
Fatigue and Stress (A NASA Report)
Initial Report
ACN: 2121377
| We were flying an inspection of a section of power line. From the starting point I flew in reverse motion to follow the line to the end point. Near the midpoint of flight, the sensor requested a yaw motion. I finished the mission, with 32% left on my batteries. I started home, not realizing my perception of the drone orientation was not correct. When I moved to come home, the motion was in an unexpected direction, and I lost sight of the craft. Knowing I was at the max of 400 ft AGL and well above any obstacles I used the distance from home in an attempt to return home. The batteries hit 20% which was our minimum setting. I was unaware the craft started descending when the batteries reached the minimum setpoint. I hit the return home button, the craft continued to descend into a tree approximately 1700 ft from my launch point. |
CHIRP Comment
The Board had the following comments:
- As part of the Operator training and their pre-flight checks, the pilot should have seen that the settings had been configured such that the aircraft would land when the remaining battery reached 20%. The 20% battery setting should have been set out in the Operations Manual if it was a company Standard Operating Practice.
- Using the distance from home figure on the controller to help determine orientation manually was an excellent back up plan for when the pilot lost sight of the Drone.
- The report doesn’t note the Drone type, but 1,700 ft is a fair distance away from the home point and this would have made seeing and having any sort of perspective on a small Drone, difficult. The pilot lost situational awareness. In the UK the rule is that a pilot should always be able to see the orientation of their Drone. In the USA things may be different!
- Part of understanding Human Factors includes being able to recognise the limitations of one’s own capabilities. If you do not have a good feel for what your own personal limitations are, it is going to be difficult to prevent yourself from exceeding your own limitations. It looks to us as if there is an element of the pilot not fully appreciating their own limitations, that has come into play during this occurrence.
- Although it isn’t specified, the report details imply that the Operator is undertaking commercial work. As such they will almost certainly have a Safety Management System in place. This occurrence will no doubt get recorded in the company’s SMS and will lead to an analysis of the root cause of what happened. This will also provide an opportunity to work through an exercise on how to do things better in the future.
- A two-crew operation, might have made a big difference in this situation.