On 21 November 2013, an A330 rejected its takeoff from Brisbane after an airspeed indication failure. Following maintenance intervention, a similar airspeed indication fault on the subsequent departure was reported to have been detected after V1. Once airborne, reversion to Alternate Law occurred and slat retraction failed. After an air turnback, it was discovered that the cause of both events was blockage of the No. 1 Pitot Head by a mud-dauber wasp nest which was created during the initial two hour turnround at Brisbane. Investigation of a 2014 event to a Boeing 737 at Brisbane with exactly the same causation was noted.