Plans for a Railway to Melbourne Airport go back as far as plans for the Airport itself. The original plans had the railway running either alongside, or down the centre of the Tullamarine Freeway. There were also plans to build a railway instead of the Freeway, these plans were dropped in favour of the Tullamarine Freeway option.
I have heard that and can believe that, but still, is there a source that mentions them. Yes, a railway within or alongside the freeway might have been best.
Plans for the railway to run alongside or in between the freeway were shelved with the hope of revisiting at a later date, but since then the freeway has been widened (and is in the process of being widened yet again) and the corridor now has no space for a railway so those plans are now no longer a viable option.
So they widened the freeway instead of building the railway. Oh no!
Probably, but without the use of a suitable time machine, I don't really see how that matters.
Here's the key. First of all see this
. And guess what, I did a bit of searching, and I found, among cities mentioned, that London has had a rail link to Heathrow since 1977, the Chicago O'Hare has been served by rail since 1984, Atlanta airport since 1988.
But the key here is as thus; Before commercial jet planes, most intercity travel was by train. Intercity trains in this country, then as of now, travelled between the centres of cities as all our state capitals have been able to bring surface rail right into the city centres.
Planes only fly between the outskirts of urban areas and don't serve the cores, so there needs to be some land transport to get people between the Airport and the city centre. A high capacity fixed route does best, and this means heavy rail. An airport rail link means less demand for parking at Airports and more space for other things. People thus won't have to rent cars just to go between the Airport and the city centre, nor take a bus or taxi.