Boeing's Phantom Works and the University of California are collaborating to develop avionics to physically prevent an aircraft from flying into restricted airspace.

Seen as a way of preventing a recurrence of the 11 September events, the team wants to pre-program aircraft avionics with the GPS satellite navigation co-ordinates of no-fly zones, creating "soft walls" around city centres and other identifiable targets.

When an aircraft approaches one of these no-fly zones the flight computers would gradually try to steer the aircraft away, and would oppose pilot-commanded manoeuvres which would cause the aircraft to breach the zone. The system would include an on-board database of the GPS co-ordinates of the no-fly zones. For modern fly-by-wire aircraft, installing soft walls would only require software changes.

The technology could provide a simpler alternative to other proposed solutions such as ground-controller intervention, which require radio links between the aircraft and the ground that can be jammed or hacked. Boeing has asked the US Department of Defense for more research funding for soft walls, as it wants to test the algorithms in high-fidelity simulators and, eventually, aircraft.

Phantom Works says the solution is a better alternative for flightcrew than being shot at or being commandeered from the ground, but pilot reaction will need gauging.

Source: Flight International