Automation pulling the rug from under the pilot's feet
...before the fault detection schemes switch it off (A/THR & A/P).
Beyond the A/THR chasing declining airspeeds and reducing the upper aerodynamic margin before being switched off, could it be that the A330 alpha protection laws had also reduced the plane's AoA reacting to the same declining airspeeds ? An Airbus in approach (AP off, A/THR on in managed speed) with substained high surface winds was surprised by a sudden wind drop (-20 kts in a few sec on the airspeed) and began to sink, the pilot tried to abort the approach/landing and to initiate a go-around but the AoA laws prevented it (reacting to the airspeed drop), by inducing a nose down that the pilot could not overrule. What about a button on the stick for the pilots to overule any automation, primary reflexes of the A330, protection laws included ? full authority (like on Airbuses operating flight tests at the limits of the envelope ?)
Jeff
Last edited by Hyperveloce; 26th Jul 2009 at 18:15.