You can fly west to Australia, but there are factors that influence flight paths, and flying directly west may not always be the most economical route. Airlines consider cost-effectiveness when planning routes.
One major reason that planes may not fly directly west to Australia is due to fueling costs. Airlines aim to reduce these costs by making fuel stops at various airports in Asia. Transpacific flights are long, usually lasting 11 to 12 hours, and require significant fuel.
