Originally Posted by
tdracer
Quagmire, when Boeing became a delegated authority, they implemented robust protections against "Undo Pressure" - arguably much better than before delegation. ............ Educated guess is that it simply wasn't identified as a flight critical system and didn't get the level of scrutiny appropriate for a system that can have catastrophic consequences if it malfunctions.
Nice to hear DER pressure has been alleviated somewhat. ... Agreed, pitch trim in a split cockpit from 1 bad AOA vane was being thrown to the pilots to sort out, because it could be handled. Pilot backup in this case. This philosophy should be questioned.
Originally Posted by
MarcK
In the GA world, there is a
probeless AOA , description
here, based on Sperry Patent #3,948,096.
Yes, the patent describes a way of geting AOA from other non-vane sensors (air data & inertial) via complementary filtering & kinematic reconstruction, an early stab at analytical redundancy which can be very useful.. In fact all sorts of variations have been tried out over the years...Sperry was the first company I worked for, and the patent was by Harry Miller. (The B-2 does some amazing software tricks.)
MickG0105 reported above: Last week FAA spokesman Greg Martin said, Quote:“the angle of attack values used by several systems, including the air data, the fight controls, the stall warning, etcetera, the safety analysis for each of these systems are currently being reviewed.”
When writing pitch control laws, the rule is to avoid use of dual sensors in favor of triplex sensors only, where the elevator is involved especially. AOA failures shouldn't affect autopilot modes anyway. This nose down stall protection is similar.