Air Traffic Skills Assessment (ATSA) Practice Test

When one aircraft estimates its position over the Initial Approach Fix (IAF) for the Instrument Landing System (ILS) twenty minutes before another aircraft, it indicates that the first aircraft is well ahead in the approach sequence. In this scenario, there is adequate time for the second aircraft to be sequenced into the approach without causing concern for separation.

In air traffic control, the established standards for separation typically require that aircraft are sufficiently spaced both in terms of distance and time to ensure safe operations. Given that there is a twenty-minute gap between the two aircraft's estimates of reaching the IAF, this time interval provides an ample buffer to maintain separation.

Since the lead aircraft will complete its approach well before the second aircraft arrives at the IAF, no special instructions for holding, vectoring, or altitude adjustments are necessary. Thus, the appropriate action is to recognize that no separation is required due to the significant time difference, allowing for a safe and efficient approach sequence for both aircraft.