I have read through the report again. It is as bad as I first thought. The author/investigator goes well beyond the normal practice for a factual report in order to praise the crew.
I believe that the pilot's performance was less than ideal (see below) but the intent of the author/investigator seems to be to protect the pilots by building a wall of praise around them.
This praise goes a bit too far as it involves too much opinion.
Snippets from the report are as follows. I have bolded certain words:
The flight crew’s responses to the emergency were timely and appropriate.
... the flight crew worked together to provide the captain with all the information he needed to fly the aircraft.
The aircraft only descended a total of 690 ft during the first pitch-down. Although this was due in part to prompt action by the flight crew ...
The captain’s sidestick responses to both pitch-downs were prompt.
However, in addition to being timely, the captain’s sidestick responses were also of the appropriate magnitude.
... the crew’s decision to divert to Learmonth was appropriate.
These tasks were performed with a high degree of coordination and effectiveness by the flight crew.
The flight crew’s responses to the warnings and cautions, the pitch-down events, and the consequences of the pitch-down events, demonstrated sound judgement and a professional approach.
"Professional"? That would be a word appropriate to a PPRUNE post, but not an ATSB Final Report.
There were other passages that contained the words "prompt" and "immediate" in relation to pilot actions. There was nothing in the report that was even slightly critical of the pilot's performance.
The report is suggesting that the pilot's performance was flawless. Was it?
The pilot's were confused as to which law the flight computers were in. The law switched to "alternate" after the second pitch down and remained that way until landing. The pilots believed the computers were in "direct" law.
Being in "alternate" law, however, meant that there was thus a greater chance of further, misguided control inputs by the flight computers.
I believe there should have been more effort spent on getting the computers into "direct" law. The pilot's belief they were already in "direct" law seems to have been based on a (flawed) observation by the captain regarding the auto-trim.
It appears to me that the pilots were overwhelmed to some degree, which should be a concern given that:
1. The fault was minor;
2. The aircraft was in clear VMC conditions in broad daylight;
3. There was a 3,000 metre runway less than 100 NM away;
The author/investigator seems to have excused the pilots, on the grounds that they were confused.
After the first pitch-down, the flight crew were presented with a situation that was even more confusing ...
The report identifies a couple of safety issues but fails to identify what, to me, are the more significant safety issues. Those are:
1. That the flight computers (in "normal" law, no less) will quite happily command elevator deflections that are capable of producing vertical accelerations of the magnitude experienced in this incident;
2. That the warning/messaging systems, in the case of a minor malfunction, can so easily confuse the crew to the point where they no longer feel they can "trust" the messages/systems;
3. The pilot's management of the flight computers. They knew there was something fishy with the computers but their efforts at isolating, to the greatest degree possible, the computer-generated control inputs, were insufficient.
The author/investigator could have sought advice from Airbus and Qantas regarding the performance of the pilots but does not appear to have done this. Instead, he/she is content to describe it with words like "timely", "appropriate" and "professional".
Poor job, ATSB. Can do better.