I-2021. The logging of flight time on instruments as legislated by the Australian Civil Aviation Authority goes back to the wartime days where RAAF pilot log books had a column for what was then termed "Actual" instrument flying. It had nothing to do with IFR or VFR flight plans. It was all to do about whether you were flying the aeroplane in clouds when of course you relied on the flight instruments to keep blue side up. The inside cover of RAAF pilot log books had the following instructions (among other things):
13. Recording of Instrument Flying Time...Instrument flying times are recorded in Columns 9 and 10 of the Pilot's Flying Log Book as either "actual" or "simulated" instrument flying as follows:
(a) All flying time when the aircraft cannot be controlled by reference to external visual aids and all manoeuvres are carried out solely by reference to instruments is to count as actual instrument flying. ...All flying time when conditions artificially created demand that all manoeuvres be carried out solely by reference to instruments is to count as "simulated" flying time.
Flying on autopilot was not considered for the purpose of logging instrument flight time based on the obvious premise that specific instrument flying handling skills were not needed for this purpose.
Different civil aviation authorities have different rules, of course. In basic terms, an hour of manual flight on instruments in IMC whether it be in a Cessna 172 or a Boeing 747 is worth heaps more in sheer flying experience than ten hours studiously gazing at an automatic pilot doing the same job - if you get my drift..