An Informal ACA is commonly used and is not depicted on charts, and can be established by using which separations?

An Informal ACA is commonly used and is not depicted on charts, and can be established by using which separations?

• A. Lateral
• B. Altitude
• C. Time
• D. Lateral, Altitude or Time

Answer: (D)

An informal ACA is used when there isn’t a charted airspace coordination area, so deconfliction is achieved by applying separations in one or more dimensions. You can establish it with lateral (horizontal) separation to keep assets apart along the ground track, altitude (vertical) separation to raise or lower flight levels, or time separation to ensure actions don’t occur at the same moment. Because the question asks which separations can be used to establish an informal ACA, the option that includes all three—lateral, altitude, or time—best matches the real practice. In some scenarios any one of these separations will work, but the comprehensive answer correctly reflects the available methods for informal ACA.

An informal ACA is used when there isn’t a charted airspace coordination area, so deconfliction is achieved by applying separations in one or more dimensions. You can establish it with lateral (horizontal) separation to keep assets apart along the ground track, altitude (vertical) separation to raise or lower flight levels, or time separation to ensure actions don’t occur at the same moment. Because the question asks which separations can be used to establish an informal ACA, the option that includes all three—lateral, altitude, or time—best matches the real practice. In some scenarios any one of these separations will work, but the comprehensive answer correctly reflects the available methods for informal ACA.