Which nighttime operation is strictly prohibited for an aircraft without position lights?

The operation that is strictly prohibited for an aircraft without position lights is flight after sunset to sunrise. Position lights, or aircraft lighting, are essential for visibility and safety, particularly during nighttime operations. These lights allow other aircraft and ground personnel to see your aircraft, which is crucial for avoiding collisions and maintaining safe distances in the airspace.

Flying during hours of darkness, which extends from sunset to sunrise, poses significantly heightened risks. Without position lights, an aircraft becomes nearly invisible in the dark, increasing the chances of accidents. Therefore, regulation prohibits such operations to ensure the safety of all air traffic.

The other options, while relevant to flight operations, do not specifically entail a strict prohibition due to the absence of position lights. For instance, bad weather can make flying hazardous, but it does not solely hinge on whether an aircraft is equipped with position lights. Similarly, low-altitude flights may be restricted under different conditions but are not inherently tied to the use of position lights. Additionally, flight after dark generally includes flights after sunset, but the regulation specifically focusing on the nighttime operation of missing position lights makes the time frame from sunset to sunrise distinct regarding safety protocols.