Was going by googlemaps which said 22 mins.
Be careful when using googlemaps to calculate driving times. If you do a directions search from Caroline Springs to Tower Rd, Melbourne Airport it will direct you via McNabs Rd. Unfortunately there is no access to Melbourne Centre/Tower/Training academy from McNabs Rd as the gate is locked. Access is via Operations rd.
I would avoid Strathmore Heights as it is close to YMEN. In particular it is close to the newly opened Police Airwing/Air Ambulance base which has exemptions from the curfew unless you like the sound of choppers all night. I also believe the Fire Fighting aircraft are based near there as well during summer and the Erikson Aircrane is very noisy. Gowenbrae will have similar problems with the noise from YMEN but now where near as bad due it being a little further away.