Three incidents at Gladstone Airport have important messages for regional aviators. The incidents, captured on CCTV footage, show three high-capacity passenger aircraft taking off at night without activating the runway lighting.
Gladstone is a non-towered, uncontrolled airport operating on a common traffic advisory frequency. The runway lighting was controlled by a pilot active lighting system that was combined with an aerodrome frequency response unity. Once activated, the lighting remains on for 30 minutes from the time of activation or reactivation. In two cases investigated, the lighting deactivated between boarding and departure. In the other the lighting was not activated at all.
All flight crew interviewed advised that, during the taxi and take-off roll, they did not notice anything unusual or problematic with the airport lighting or environmental conditions at the airport. In addition, they reported that they had no difficulties maintaining directional control during the take-off. Until the ATSB contacted them, the crews had not been aware that the lights had de-activated in between boarding the aircraft and the aircraft taking off.
These incidents highlight the potential hazards associated with change blindness, inattention blindness and expectation bias.
Change blindness occurs when a person does not notice that something is different about the visual environment relative to before the Potential Hazard change. Research has shown that in some cases, quite dramatic changes are not detected, particularly if changes occur when the observer is not looking at the relevant part of the visual environment at the time. In this instance the crews did not notice the difference between the airport lighting when they were boarding versus when they taxied out for departure.
Inattention blindness occurs when a person does not notice an object that is visible, but unexpected, because their attention is engaged on another task. In this instance the absence of lighting was noticeable, if looked for, and the crews probably had an assumption or expectation that the lighting was on.
In simple terms, expectation bias is ‘seeing’ what you expect to see even when it is not there—in this case, runway lighting being on.
Read the report: Take-offs without runway lighting - VH-FVL (ATR-72), VH-FVU (ATR-72), VH-QOK (DHC-8)
You can find this and other investigations in the ATSB’s Aviation Short Investigation Bulletin. The bulletin highlights valuable safety lessons for pilots, operators and safety managers.