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A study was conducted to evaluate the effects of primary flight display (PFD) terrain depictions on pilots’ performance of recoveries from unknown attitudes. Forty pilots participated in the study, each group of eight using a different display format. The five conditions consisted of combinations of terrain depiction (none, full-color terrain, brown terrain) and guidance indications (pitch and roll arrows). Participants flew baseline trials in the Advanced General Aviation Research Simulator using a common electronic attitude indicator and then performed recoveries from unknown attitudes (UARs) using one of the PFD formats. Performance measures included initial response time, total recovery time, primary reversals, and secondary reversals. No significant effects of the primary independent variables were found on any of the performance measures. Posttest interviews indicated the participants preferred the directional-arrow indicators and had no preference for or against the presence of terrain depictions during UARs, focusing primarily on the zero-pitch line as a reference. It was concluded that the specific terrain representations examined did not pose a hazard to the identification of and recovery from unknown attitudes as long as a zeropitch line of sufficient discriminability (contrast and size) to all backgrounds was present.