Miscellaneous - Other involving a de Havilland Canada DHC-8-102, VH-WZI and Piper PA-34-220T, VH-BJQ, Mildura, Victoria, on 11 June 1993

VH-WZI entered the Mandatory Traffic Advisory Frequency (MTAF) area with the intention of a straight-in approach. The captain of VH-WZI copied traffic information on two other aircraft from Flight Service and monitored these on the MTAF frequency. At about 4 miles out turning final he copied an aircraft on Flight Service frequency taxiing at Mildura. VH-WZI immediately tried to contact the taxiing aircraft on both the MTAF and the Flight Service frequencies, but without success. Another aircraft in the area confirmed that the taxiing aircraft, a Seneca VH-BJQ, did give a call on the MTAF frequency. It is believed that this call probably occurred as VH-WZI was calling the taxiing VH-BJQ on the Flight Service frequency. The pilot of VH-BJQ is adamant that he called both on the Flight Service frequency and on MTAF before he entered runway 27 to back-track for take-off. After about the third attempt VH-WZI managed to contact VH-BJQ on the Flight Service frequency, by which time he was well down the runway with no chance of exiting before the arrival of VH-WZI. VH-WZI asked the pilot of VH-BJQ to expedite at which time the captain of VH-BJQ was about 100 metres from the take-off threshold and had not fully completed his pre-take-off checks; thus he refused to expedite and suggested that VH-WZI should carry out an orbit.

The captain of VH-WZI considered that the failure of the taxiing aircraft to ascertain the position of VH-WZI before entering the runway was worrying. The captain of VH-BJQ claims that VH-WZI was a long way out when he elected to back-track. Neither the captain of VH-BJQ or his passenger saw VH-WZI until it was turning finals at about 3 or 4 miles out by which time VH-BJQ claims to have been backtracking for about 2 minutes.

Significant Factors

The following factors were considered relevant to the development of the incident:

1. The pilots of both aircraft had problems communicating with each other.