The Civil Aviation Safety Authority (CASA) has suspended a far north Queensland airline for operating with "serious and known defects".
CASA says Cairns-based Barrier Aviation Pty Ltd would pose a serious and immediate risk to air safety if it was to continue to fly.
"CASA has evidence of Barrier Aviation directing pilots to fly with serious and known aircraft defects, as well as not recording those defects on aircraft maintenance documentation when the defects became known," a aviation regulatory body said in a statement.
"The suspension follows an audit of Barrier Aviation, which revealed a range of maintenance related deficiencies."
The suspension, which began on Sunday, is in force for five working days.
However, CASA can apply to the Federal Court for an extension.