The government's Civil Aviation Authority said US authorities have advised it that a gasket fitted to the fuel injection system of engines by three US manufacturers - Lycoming, Teledyne Continental and Superior Airparts - may not be safe.

'At the worst case scenario your engine could lose power in air,' authority spokesman Peter Gibson told Australian Broadcasting Corp radio.

Some 1,400 operators - mostly crop dusters, musterers and private owners - with planes that may be affected are required to get them checked before they fly them again, the authority said. Major airlines were not significantly affected.

US aviation authorities recorded 18 incidents of failure of the gasket type, the authority said.

The order applies to planes that have had engines rebuilt, serviced, overhauled, repaired or bought since Aug 22, 2006.

The checkup is simple and takes a qualified engineer about one hour, Mr Gibson said.

'It's really removing a bolt in the fuel injection system, looking at the gasket and - if there are problems - replacing the gasket and putting it back together,' he said. -- AP