Hate to tell you this David, Macquarie Centre is 11 miles (as the crow
flies) from the threshold of R/W 16R and about 1.5 miles west of the
extended centre line of that runway. If you get hold of a Sydney street
directory, draw a line from the airport, over the northern end of the
Gladesville Bridge and the old Channel Ten studios on Epping Road (where the
M2 starts) up through West Pymble will give you some idea why you are
getting a/c near by.

Cheers,

Avsec