What is the separation minima for longitudinal and crossing aircraft operating within an ALTRV in domestic airspace?

The correct choice of 30 minutes for separation minima between longitudinal and crossing aircraft operating within an ALTRV (Altitude Reservation for Air Traffic) in domestic airspace is based on established standards for safe air traffic management. This interval provides a sufficient buffer to account for variations in speed, altitude, and flight path, which helps ensure that aircraft do not come into unsafe proximity during their operations.

In an ALTRV, the separation requirement is crucial given that the airspace may be subject to unique operational characteristics due to the presence of special activity or other factors affecting air traffic. The 30-minute separation minimizes the risk of collision and helps facilitate effective traffic flow, especially in areas where typical radar or visual separation may not be feasible.

Implementing a narrower timeframe, such as 20 minutes, would introduce additional risk, as aircraft may not have adequate time or space to maneuver safely. The other choices like 40 minutes or 50 minutes, although conservative, could result in inefficiencies in air traffic operations, potentially leading to increased congestion and delays without providing proportional safety benefits.

Thus, the choice of 30 minutes strikes a balance between safety and operational efficiency in airspace management within an ALTRV context.