The Impact of Lower Degree Automation Reliability on Higher Degree Automation Failure Detection in Simulated Air Traffic Control

Objective:
To determine how lower degree of automation (DOA) reliability impacts human response to a single higher-DOA failure in simulated air traffic control conflict detection.

Background:
Higher-DOA systems apply higher levels of automation to later stages of human information processing. Higher-DOA typically results in better routine performance, and lower-DOA with better automation failure response. If both are provided and lower-DOA is reliable, it could support higher DOA failure detection.

Method:
Participants (N = 192) received a combination of lower-DOA and/or higher-DOA. Lower-DOA highlighted aircraft conflicts and near-misses, leaving participants to manually resolve conflicts. Higher-DOA resolved conflicts. Automation failed once. Participants were provided one of four types of automation: lower-DOA, where lower-DOA failed (LF); higher-DOA, where higher-DOA failed (HF); both lower- and higher-DOA, where only higher-DOA failed (LHF); or both lower- and higher-DOA, where both failed (LFHF).

Results:
When only the higher-DOA component of combined lower- and higher-DOA failed (LHF), participants detected the automation failure 23.6s faster and more accurately (miss rate = −.08) compared to higher-DOA only (HF). However, more participants missed the automation failure when lower-DOA failed (LF = +.42; LFHF = +.15), compared to the HF condition.

Conclusions:
Reliable lower-DOA can support higher DOA failure detection when both are presented. However, poorer automation failure detection with lower-DOA failure suggests participants over-relied on aircraft highlighting to direct attention to potential conflicts.

Applications:
Providing both lower- and higher-DOA together could be beneficial when higher-DOA fails but lower-DOA remains reliable, but conversely, detrimental if lower-DOA also fails.