Pax and Crew File Lawsuit Against Airbus

[CONF iture]

Thanks for the reply swh, interesting reading.
Obviously, you seem to have a good technical knowledge of the 777, which I don’t, but still, I have to stand to my earlier post.

The 777 initially pitched up under AP which was following the FD commands. AP disconnect came up only at time 17:03:16 Airplane was already 10 degrees NU.
Then the manual FWD displacement of the control column didn’t seem aggressive enough to stop the pitch up movement. The guy seems undecided : Do I follow the FD or I do it my own way ?
Another point is : How was the trim at that moment ? I haven’t seen that piece of information …

As stated by Boeing, you are correct to say that not only the AP was affected by the erroneous accelerations, but also the manual flying.

Erroneous accelerations will affect the Primary Flight Computer (PFC) control laws during manual and automatic flight

But it is also said :

The flight crew should disconnect the autopilot and manually fly the airplane. Although initial manual control forces may be high, the affects of the ADIRU anomaly on manual control forces are expected to diminish within 10 seconds and should be back to near nominal within 2 minutes.

The flight crew should also disconnect and disarm the autothrottle via the arm switches on the MCP if there is any undesired behavior.

I find this idea of direct mode switch interesting, Airbus should have a serious look to it.

Questions :

1. Is it a single DISC switch for all 3 PFCs or one switch per FPC ?
2. Except from an automatic transfer, is there an ECAM or QRH procedure to command to switch to direct mode, or is it something left to the pilots judgment ?

The main reason for the different outcomes from the two events was that 9M-MRG only occurred 18 minutes after departure. It actually experienced much higher accelerations, rates of climb/descent, and pitch range over the A330 event. If this happened several hours into the flight after a meal service with many people waiting to use the toilet, I think the outcome would have been very different.

Disagree on that. Rates of climb have been very significant, yes, but although real accelerations have not been published for the 777, noway they were at the QF72's level.

It is also apparent that over 30 AoA spikes were recorded in the FDR (which was limited by the sampling rate), however 3 nose down pitch events were seen. If it was as simple as you were suggesting that it was the protections kicked in, one would assume that a correlation would then exist between all the AoA spikes and the pitch events.

No Sir. And no pilot inputs either, only protections, two of them actually :

1. The famous high angle of attack protection (alpha prot)
2. And the anti pitch-up compensation (I had never heard about that one

before reading the ATSB interim report …)

A total of 42 AoA spikes have been recorded, but only 2 of them had the requested properties to generate an undesired nose-down elevator command.
Please, read page 29 and 30 in the report for more information.