Final answer:
Safety cones should be positioned at the wingtips and engine areas on an MD80 turn flight (no ventral stairs used) to ensure aircraft and ground personnel safety.
Step-by-step explanation:
On an MD80 turn flight, safety cones should be positioned at the wingtips and engine areas (no ventral stairs used). This is to ensure the safety of the aircraft and ground personnel during ground operations. The cones act as a visual marker to indicate areas that should be avoided or approached with caution.