Ah!  The answer from Jetson 1:

Thanks for reaching out.

 

The finger-pull loop installed on our prototypes has a triple function, let us explain:

 

1. Allowing battery power to the system. As our prototypes are not yet flying with our production batteries, which have an advanced BMS (battery management system) that electronically switches on/off batteries, our prototypes need a way to manually switch on the main power on/off. This is extremely important for ground operations, with other people around the Jetson ONE. Only when the loop is installed, the arming procedure of the vehicle can start. Same goes after landing, removing the loop guarantees that no motor could unintentionally start spinning for whatever reason, again to protect the support crew or other bystanders.
2. Pulling the loop once the propellors are spinning or when you are flying will stop all motors as battery power is cut-off. When the unit would become uncontrollable it allows the pilot to make a crash landing, either because of flying low over the ground or treetops (pls don’t forget that we experiment a lot both with software and hardware, so events could happen). Please note that so far never we had to pull the loop and the Jetson always has flown as intended.
3. Pulling the loop will also activate the all-airframe parachute at the same time. The parachute is activated electronically by the flight computer if it detects an unrecoverable situation, but on top of that, the pilot has also the manual possibility to pull. Pls note that our prototypes are not equipped yet with our parachute system. Our parachute is developed by Parazero from Israel, and due to the ongoing conflict in the region, the development has seen delays we didn’t anticipate for (Force Majeure). As long as we have no parachute installed, you will not see our pilots flying high, only at a survivable altitude (ground or treetops). As our prototypes also operate remotely, we do higher flying tests with ballast and a remote pilot. We also did already several successful parachute deployment tests, but again, all tests have not been performed yet due to product delays, so we cannot yet fly manned at higher altitude.

 

Nice of them to reply. And mystery solved. 👍

 

Another cat point for Charlie.

 

😸