After how many feet is the arresting chain doubled on an MA-1A arresting barrier?

The correct information indicates that the arresting chain on an MA-1A arresting barrier is doubled after 90 feet. This design feature is crucial for the effectiveness of the arresting gear, as doubling the chain at this distance provides additional support and strength to handle the significant forces involved when an aircraft lands.

The functionality of the arresting barrier is reliant on the properties of the chain and how it interacts with the aircraft during rapid deceleration. By doubling the chain at this specified length, it enhances the barrier's capacity to safely and effectively bring an aircraft to a stop while minimizing the risk of failure due to overstressing. This is particularly important in military operations where the landing speed can be very high.

Each of the other distances provided does not correspond to the specifications for the MA-1A arresting barrier, which highlights the importance of knowing precise measurements and operational protocols for such equipment. Understanding these parameters is essential for maintaining safety and operational efficiency in aircraft recovery systems.