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Old 6th Mar 2013, 00:17
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PJ2
 
Join Date: Mar 2003
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gums;

Re, "A PAR was so easy it felt like cheating."

Yessir, done them very occasionally in the DC9. Aside from Canarsies onto 31R, that was a leg to get!

I must be out to lunch as I never realized you weren't on earth all the time! The reminder re 'derived' etc was a good one and it got me going too.

bubbers;

Re, "I think I know but Airbus training needs to include how degrading automation needs to let people understand the level of automation they are at."

I trained on the A320 in 1992, the A340 in '99, the A330 a bit later and from the get-go all three laws as well as the protections were heavily emphasized, taught, practiced and checked in recurrent rides. We knew that in Alternate and Direct laws one didn't do anything rash, quickly or rough with the airplane. While it was complicated sometimes, the ECAM was / is very good and must always be done to completion. Forgive me but really, the people who do this work aren't dull or slow.

Re, "2 degrees nose up attitude and cruise power would have made this accident a non event." Well, QED. That's about what the airplane cruises at. Monitor altitude, set power, wait, do the ECAM, get out the QRH. That's why I said very early on, "do nothing, wait..." It's not an emergency.

Regarding pitch, two to 2.5deg NU is the pitch the A330 cruises at and the thrust is already in the CLB detent, so the airplane is immediately both stable and under control which is the first rule, 'aviate'. To change the pitch attitude, (arbitrarily or via the checklist), adds workload and increases the potential for loss of SA as one departs one's cleared altitude and minds the speed, heading, etc and it delays getting on with the ECAM while the PF is ensuring that the airplane remains under control. I surmise that these are the things check airmen argue about in meetings all the time. In my view the UAS drill and checklist is a mess and can, if improperly understood and taught or badly executed, reduce and not increase flight safety.

One thing to note that those who fly these airplanes may not know is, a transport airplane can depart controlled flight very gently almost languidly and smoothly, without broadcasting what it's doing. In the departure from controlled flight into a severe loss of control there was nothing violent about this accident. Even the descent would have been "languid" in terms of pitch, roll, yaw, gee despite the buffeting.

As you must know instinctively from experience, it isn't 10 or 15deg NU that would get the attention of a transport crew, it is a degree or two above nominal. So if the airplane is in stable, level cruise at 2 deg, then a pilot taking it to 3 to 5 degrees (yielding about a 1000 to 1500fpm climb), and keeping it there would require an immediate taking of control to stop a loss of control event and also regain the cleared altitude. Seven or eight degrees pitch at cruise altitude and Mach is positively frightening in my book.

When the ATs disconnect, you'd have to bring the levers back a bit to maintain the previous cruise setting but you'd never overspeed the airplane if you left the TL's alone.

Lyman;

Re, "Is this our friends?"

I don't know. I don't know why this happened. All we know is a bit of how.

HN39;

Re, "Yes, it is possible for AoA to exceed Alpha Prot in Auto."

Absolutely correct. Ask any carrier flying into Mexico City in an A320 about the sharp left turn onto the 5's from the 160R of SMO with the speed right back, landing flap out and an encounter with a bit of turbulence in the turn. It will also occur if one retracts the flaps too early, AP on or off.

Last edited by PJ2; 6th Mar 2013 at 00:27.
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