While RR_NDB is working on his next concept, let me throw out one of my own.
There is no doubt that the best course of action with UAS in cruise is to do nothing while you size the situation up. With a little more smarts in programming, the flight control system could do the same thing.
Process runs like this:
- Oh Oh, lost the airspeeds!
- Wait, we are in cruise, instructions say do nothing and warn the crew that they may have to take over.
- Power table lookup says cruise power for current flight environment is X, set power to X, maintain Normal law.
- Monitor airspeeds to see if we can get a valid airspeed.
- Airspeeds agree on 90 knots? Not in the acceptable range-disregard.
- Airspeeds now say 271 knots. In acceptable range. Advise crew that we are resuming normal control.
- End of allowable dead reckoning period (where control would then pass to the crew).
How you handle loss of airspeeds in climb and descent could probably be handled pretty well with a lookup table as well. That only leaves Approach and the transition right after takeoff to climb speed.
Can they build this reasoning into the computers? Can they certify it? If so, most of the problem is solved.