Originally posted by Gabriel
View Post
2 h 09 min 58 - Speed handling changes from managed to selected. The selected Mach is 0.8.
2 h 10 - Pitch attitude decreases from 1.8° to 0° in 3 seconds. In 8 seconds, the N1 commanded and the N1 change from 100% to 84%.
2 h 10 min 05 - The A/P2 disconnects.
2 h 10 min 08 - The FD 1 and 2 become unavailable. The A/THR disengages and the THR LK mode isactivated. The N1 are at 83 %.
Q: Is 0-3° pitch (known values) and 83% N1 at their current weight and altitude FDnH?
Complex modern aircraft have stealth factors. Procedures are needed to overcome them.
Now Evan, googling some I found that ATLcrew is so right that official Airbus documentation explains why they added the "If the safe conduct of the flight is impacted" condition to the memory items and how they propose to train the pilots to specifically NOT apply the memory items unless the safety of the flight is impacted and how that relates to ground/obstacle clearance.
However, one can extrapolate: The flowchart showing the decision tree to determine if memory items are called for involved two options:
- Safe Conduct of the Flight Affected: Unreliable Airspeed Procedure
- No (Safe Conduct of the Flight Not Affected): ADR Check Procedure
The scenario it is showing for "No" is "Speed between CAPT and F/O PFD starts to diverge while in climb."
That is NOT an "NAV ADR DISAGREE" ECAM message and a sudden loss of autoflight and reversion to alternate law caused by the simultaneous obstruction of multiple pitot tubes (an emergency at hand). That is an indication to run the ADR check procedure and to isolate a faulty unit (a problem developing). There is no indication of loss of autoflight under the NO scenario.
Does the sudden loss of autoflight and reversion to alternate law affect the safe conduct of the flight? Absolutely!
So, while disturbingly vague and potentially misleading, this doc seems to me to warrant the memory procedures if ""NAV ADR DISAGREE" is encountered at any altitude.
Furthermore, the memory items continue to have separate pitch/power values for flight above FL100. So that sort of blows any theory that these memory items are only for "how that relates to ground/obstacle clearance." Wouldn't you agree?
What did we learn from AF447? What did we learn about human factors when pilots have no memorized and practiced procedure in their head and improvise under the disorienting affects of being startled and stressed?
Bottom line (hasn't changed): If the crew of AF447 (and every other instance of high-altitude UAS) had applied the standard memory item pitch and power values, nothing bad would have happened, whereas when left to individual pilot improvisation, anything can happen. Why do pilots (and apparently now, the industry itself) continue to resist that hard lesson and that self-evident truth?
Comment