Originally Posted by
todd1200
If you're an FO I don't think you have to worry about it, since the reg applies to acting as PIC.
Carefule, trhere's some confusion here...
Under 121, both PIC and SIC must make 3 takeoff's and landings within the past 90 days... day, night, IMC, or VMC the conditions don't matter. This will provide 121 landing and IFR currency.
Technically the 91 rule does not apply, since 121 pilots do not have to do the night landings for night currency.
However...a current 121 pilot who flies GA under part 91 MUST meet all the usual part 91 rules. You can be 100% airline current but zero% GA current.