Robotshop is selling a “FAA Compliance Tether for Multi-Rotor Drone,” which is a 3D-printed spool with 149-feet of thin, military-grade nylon line. The description states:

The FAA Compliance Tether for Multi-Rotor Drone is a tethered multirotor solution that will allow you to use your Multirotor for hire commercially without being fined by the FAA. This is a small 3D Printed Spindle with two metal protrusions sticking out of the bottom so it can be stuck in the ground. The spindle comes spooled with 149 feet of thin, military grade nylon line. One end of the line is secured to the spool and the other end attaches to the bottom of your Multirotor. The altitude of 149 feet is highest altitude allowed without having blinking lights attached to the line spaced every feet.

The regulations (or lack of, really) are crazy right now. Do the same flight twice—once for fun, and once for a penny, and the second one isn’t allowed by the FAA. Someone in our quadcopters group called the FAA and asked them about this device, and they confirmed that commercial flights are allowed when tethered without the need for a Certificate of Authorization.

This spool looks fine for deployment of a line, but pulling it all back in would be complicated. I can’t imagine that you’d be able to do many flights without resulting in a hopeless tangle of nylon. I think a fishing rod and assistant is a better way to go, but for $99, this will get you going immediately.

The product comes with an “FAA compliance certificate,” but the site doesn’t claim that the certificate actually comes from the FAA. It seems to me that the certificate merely implements FAA rules, which requires a serial number on the aircraft during commercial operation.