It occurred that there ought to be a "safe mode" for planes straying into sensitive airspace on purpose or not.
I would propose a small black box hooked into the avionics system that could lock out normal control input and force the plane to climb to a safe altitude and circle. The circling flight path should be made to that the plane slowly drifts out of the area.
The box would have to be inaccessible from inflight access, and should be triggered by a powerful radio signal with a particular message. The strength of the required signal should be such that it would be literally impossible to generate in absence of a full blown commercial radio station.
Once the plance has drifted far enough away that the signal strenght has gone down, control would be restored.
Even if terrorists were to take over a radio station and broadcast the message the consequences would be harmless, and the powerful signal is extremely easy to find and shut down by authorities.
In order to overcome this the terrorists would have to attack radio stations on the ground simultaneously with the hijackings. Since there are many commercial stations with high broadcast power in most areas of value, backups are easily found.
This idea is hereby submitted to the public domain, and cannot be patented.
Slashdot Mirror
It occurred that there ought to be a "safe mode" for planes straying into sensitive airspace on purpose or not.
I would propose a small black box hooked into the avionics system that could lock out normal control input and force the plane to climb to a safe altitude and circle. The circling flight path should be made to that the plane slowly drifts out of the area.
The box would have to be inaccessible from inflight access, and should be triggered by a powerful radio signal with a particular message. The strength of the required signal should be such that it would be literally impossible to generate in absence of a full blown commercial radio station.
Once the plance has drifted far enough away that the signal strenght has gone down, control would be restored. Even if terrorists were to take over a radio station and broadcast the message the consequences would be harmless, and the powerful signal is extremely easy to find and shut down by authorities. In order to overcome this the terrorists would have to attack radio stations on the ground simultaneously with the hijackings. Since there are many commercial stations with high broadcast power in most areas of value, backups are easily found. This idea is hereby submitted to the public domain, and cannot be patented.