Hi D1,
Can anyone tell me more about this?
It's all explained in FCOM 4.5.10.
"If the GPS is available, initialization is automatic, using the GPS position. Pilot intervention is not necessary.
However, automatic initialization may be manually overriden by pilot entry, at any moment during the alignment phase. In this case, perform the following procedure as soon as possible, to prevent delays if an alignment error occurs : etc."
We consulted the GPS perdiction page, but no prediction found.
If you don't tell the IRS its position initially, how can it predict what satelites will be visible?