Wasps have been identified as an "ongoing hazard" at Brisbane Airport following an investigation of two emergency landings in as many years by Australia's air safety watchdog.

An Etihad Airways Airbus A330 was forced to make a heavy landing at Brisbane on November 21, 2013 – almost 18 tonnes over the plane's maximum landing weight – after a wasps' nest blocked an air speed sensor.

The Etihad A330 declared a mayday after mud dauber wasps built a nest in an important sensor. Credit:ATSB

It had just taken off from Brisbane bound for Singapore at 1.45pm when the crew noticed airspeed discrepancies, declared a mayday and decided to return to Brisbane, landing with a fuel-laden weight of 199.7 tonnes.

The A330's maximum landing weight was 182 tonnes.