Google calendar is my primary calendar. To show micrew info on my wife’s calendar (she uses iPhone calendar), I sync MiCrew, which puts all the events into my iphone’s Calendar. Then I go through each event (in the Calendar app) and change the calendar that the rotations are assigned to from the default “micrew” to my google calendar, which is shared with my iPhone. So basically my iPhone calendar is just a conduit to get flying events onto my google calendar. Just takes a couple minutes once a month, and the events instantly appear on my Google Calendar.

Then my wife can just display my google calendar, and voila, she can see my flying schedule.

Not very efficient for lots of one-day events (reserve/vacation), but works well for a line of 3-6 rotations.

Not sure that fully meets your needs, but hope it helps.