Final answer:
The provided materials do not directly answer the query about aircraft storage and preservation timelines. They discuss unrelated events and regulations. However, FAA regulations require commercial airliners to maintain specific separations to avoid in-air collisions.
Step-by-step explanation:
The question about how many days an aircraft can go without flying before it needs to be placed in a preservation state is not directly answered in the information provided. The reference material discusses an incident involving a 767 that lost power mid-flight, the air traffic control regulations for avoiding collisions, and filming weightless scenes in the movie Apollo 13. These references do not contain specific data on aircraft storage and maintenance requirements. However, in general, the duration before an aircraft must be put into a preservation state can vary based on the manufacturer's guidelines, the type of aircraft, and aviation regulatory standards. Preservation measures can include storage preparations to protect systems and components from corrosion, mechanical degradation, and other potential issues associated with inactivity.
Regarding the avoidance of in-air collisions, the Federal Aviation Administration (FAA) regulates the flight paths of commercial airliners. Airplanes are required to maintain a horizontal separation of five miles at the same altitude and vertical separation of 2,000 feet from another plane, or 1,000 feet when flying below 29,000 feet altitude, ensuring safe distances between aircraft as they fly.
Comparatively, in quantum mechanics, electrons have position restrictions similar to how aircraft are only allowed to maintain certain positions while they fly. And, notably, the movie Apollo 13 used a plane's free-fall to simulate weightlessness for its scenes, demonstrating another aspect of aviation where safety and precision are critical.