Business columnist at the Australian Newspaper Robert Gottliebsen says Australian fighter jet planes do not have the ability to shoot down a potential 'spy balloon' if there was one in Australian airspace. 

A fourth flying object was shot down by the US military over Canadian airspace at an altitude of 20,000 feet

"Our main jet operating area height is 35,000 feet - so the US who has a big fleet, did not use that aircraft, they used a much better aircraft," Mr Gottliebsen told Gary Adshead.

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