Originally Posted by HN39
The PNF was apparently looking at all three displays between 02:10:25 and 02:10:36:
Reading the three instruments (the two PFD’s and the ISIS), the PNF noticed that the airplane was climbing and asked the PF several times to descend.
Subsequently he made following selections:
02:10:40 F/O on ADR3
02:10:44 F/O on IR3
02:12:15 CAPT on ADR3
02:12:19 CAPT on IR3
02:13:25 CAPT on ADR1
Logically, PNF wanted to be sure that PF was flying with information that looked good to PNF and so that he, PNF, could be sure of what was appearing on PF's panel. (Since monitoring the PF's PFD was a bit of a stretch for PNF.)
Obviously PNF trusted the ADR3/IR3 data and likely didn't understand why PF insisted on flying around with his nose in the air.
Then later, to ensure that he could also conveniently read the ADR3/IR3 data on his PFD, he switched his displays to the same data sources. (Despite the loss of redundancy.)
That is my take on these actions. Sorry about all the acronym soup.
