The TV antenna is typically a Yagi design and a bit directional. Note most TV stations all Transmit from one central place such as Mt Coot-tha, Mt Dandenong (?) or Black mountain etc
But the band is not too far off as old VHF TV sound used the same band as FM broadcast (not digital) so the antenna will pick up something even if it's not pointing quite in the same direction. Finally, air band is VHF AM 118 to 132 MHz. A 90 degree azimuth won't help at all. That is to say if the TV antenna is pointing north and the airport is east or west. A summary of frequencies:
UHF TV 506.25 and up (irrelevant for this discussion)
VHF TV image 138.25-299.75 MHz
Air band voice 118 to 132 MHz
Air band navigation 108-117.95 MHz
FM broadcast 87-108 MHz
So yes the TV antenna can pick up quite a bit of this