Which of the following modes of operation allows the helicopter to maintain its current attitude indefinitely?

• A. SAS
• B. ATT HOLD
• C. HDG HOLD
• D. Normal Flight

Answer: (B)

The mode of operation that allows the helicopter to maintain its current attitude indefinitely is ATT HOLD. This mode is designed to provide stability by holding the helicopter in a specific pitch and roll attitude. When activated, ATT HOLD can assist the pilot in maintaining a desired orientation without requiring constant manual input, effectively reducing pilot workload during flight.

This mode is particularly valuable in conditions where maintaining a stable attitude is essential for safety and operational efficiency, such as in instrument flight or when performing tasks that require precise positioning. The helicopter's control systems work to counteract any unintended movements, thus keeping it in the set attitude until the pilot decides to deactivate the function or change to another flight mode.

As for the other modes, while they offer various forms of stability or control, they do not maintain the helicopter's attitude indefinitely in the same way that ATT HOLD does.