Hello,
I read yesterday a part of this thread about what to do when the airspeed is not available.
Originally Posted by David Horn
Originally Posted by Graybeard
The aerodynamics of the plane is a perfectly good airspeed indicator.
For a given weight and cg, the pitch angle (nose up/down), as shown on the Attitude Indicator, will indicate airspeed. Pitch down, and the plane speeds up; pitch up and the plane slows down. It's there staring at the pilot throughout every flight.
Oh, that happens to be the basic of the Unreliable Airspeed Indicator training.
http://www.pprune.org/tech-log/45283...ml#post6478838
If, as said earlier in this discussion, the pitch and thrust behavior should give enough clues to the pilot to find a solution to the problem, why can't these clues be submitted to a computer, and have the computer calculate the airspeed from these clues ?
In other words, shouldn't the autopilot software be improved to take into account this calculation and enable the autopilot to go on instead of tripping off (1)?
In other words, imagine we are not talking about an airliner but about a costly military drone. Wouldn't you want the drone to come back safely when this kind of problem occurs and to develop the necessary software ?
(1) " the computers controlling the flight switched off the autopilot after becoming confused by conflicting speed readings, caused by the icing up of pitot tubes monitoring the plane's velocity" :
Air France crash inquiry details pilots' battle for survival | World news | The Guardian ; "From 2 h 10 min 05, the autopilot then auto-thrust disengaged" :
http://www.bea.aero/fr/enquetes/vol....mai2011.en.pdf;