AF 447 Thread no. 4

[gums]

Loss of control and AF447

A previous contributor brought up “loss of control” as a major cause of crashes. Hell, it's the only cause - act of God ( microburst on short approach or a mountain wave rotor), pilot unable to handle the aircraft's capabilities ( e.g. gee-loc as we saw in the Blue Angel crash awhile back), poor airmanship (e.g. CFIT or poorly executed approaches in bad weather or worse, the Buffalo crash), etc.


What bothers this ol' pilot is the situation where the aircraft itself becomes the problem facing an airman. I specifically refer to the concerns several of us have with respect to the Airbus control laws and “protections”. And BTW, I really dislike the term “protections”, and prefer “limits” when characterizing an aircraft's capabilities to perform the mission, or most importantly, “limits” imposed by FBW systems that seem to me to be more appropriate for autopilot assistance than basic airmanship. If we're too poorly trained to do the approach or cruise or climb without an autopilot, then what in the hell are we doing hauling the SLF's about?


Make no mistake, I flew mostly by myself and used the autopilot a lot ( when I even had one, heh heh) to reduce workload and “assist”. I did not use it as the primary means of flying the mission. I also did not completely depend upon the “limits” designed for the aircraft, and kept my OODA loop very active.


So I joined this discussion when initial findings were made public two years ago that AF447 did not auger in as we usually see with a “death spiral” or loss of control surfaces or even a spin. The impact description reminded me of the situation we encountered 30 years ago with my little FBW jet once discovering that all the “limits” to “protect” us could be overcome by doing things the designers never anticipated. When the AF447 wreckage was discovered, and the latest findings were made public, I became more convinced that the aerodynamic characteristics that likely existed at impact and for some time before were the same as our pilots faced long ago.


So what's the point, Gums?


I see a design that appears more like that of a drone then a plane with a crew onboard to fly the thing when sierra happens. I see a design that provides conflicting warnings to the humans and invokes a myriad of control law reversions due to a relatively well-understood sensor failure. I see a design that continues to “protect” the humans trying to pilot the thing when “normal” flight conditions do not exist. I see a design that has not considered the possibility of the aircraft to reach an aerodynamic condition from which recovery is almost impossible, especially with all the “control laws” I seem to understand a bit better after reading all the stuff here.


I shall not understand the crew actions we have been made aware of, but in the end, I shall ascribe a significant portion of the “cause” to the aircraft design.


Respectfully,