What is the vertical spacing for number 2 in echelon formation?

In an echelon formation, the primary objective is to maintain effective visual communication and tactical positioning relative to the lead aircraft. Number 2 in an echelon formation flies at co-altitude with the lead aircraft. This configuration allows number 2 to be in a strong position for both visual reference and control, while still being separated enough to ensure safe operations and effective maneuverability.

Flying at the same altitude as the lead helps maintain a unified tactical profile, which is essential for maintaining formation integrity. This is particularly important during maneuvers, as both aircraft need to respond to changes in speed and direction cohesively. Additionally, it provides number 2 with the best vantage point to observe lead's actions and maintain situational awareness.

The other options imply different altitude strategies that would undermine formation integrity or compromise visual navigation. For instance, flying below or above the lead could negatively impact the overall coordination and safety of the formation. Thus, maintaining co-altitude is essential for effective communication and control in echelon formations.