How long must the lead aircraft be faster in the 44kt Rule to establish separation?

To establish separation using the 44-knot rule, the lead aircraft must be able to maintain a speed advantage over the following aircraft for a certain duration. The correct duration is 3 minutes. This period allows the lead aircraft to gain enough separation distance from the following aircraft, ensuring that the trailing aircraft can safely follow and maintain the required vertical and lateral separation distance.

In practical terms, this means that if the lead aircraft is flying at least 44 knots faster than the subsequent aircraft, it will need at least 3 minutes before the following aircraft can be considered safely separated. This timeframe takes into account the convergence speeds of the two aircraft to ensure adequate spacing is achieved, minimizing the risk of wake turbulence or other separation issues.

Understanding this duration is critical for effective air traffic control and ensuring safe operations within busy airspace. The other options do not meet the criteria set by the 44-knot rule and thus would not provide sufficient time for safe separation.