Sydney’s second airport will soon be up and running. How different will it be to Melbourne’s Avalon?

Key points

• Sydney's Western Sydney International Airport is set to begin commercial flights this weekend. Seven airlines have already signed up to fly from the new airport, which aims to ease congestion at Kingsford Smith.
• Melbourne's Avalon airport, which began passenger flights more than two decades ago, has only one international route, to Bali. Avalon is run by Linfox, which uses it largely for freight and logistics.
• Experts say the new airport may need about a decade to become commercially viable.