Analysis of an ADS-B in method for calculating the interval management paired approach collision safety limit

Interval Management (IM) Paired Approach (PA) is a proposed NextGen concept to increase arrival capacity at airports with Closely Spaced Parallel Runways during Instrument Meteorological Conditions. To ensure the safety of the IM PA operation, the IM aircraft must be protected from the risk of both collision and wake encounters. This is accomplished through the establishment of collision and wake safety limits that bound the longitudinal position of the IM aircraft relative to the Target aircraft. Traditionally, these safety limits have been developed offline using Monte-Carlo simulation techniques and are based on geographic and procedural characteristics of the IM PA operation for a given runway pair. This paper proposes a new method for calculating a collision safety limit (CSL) for an individual aircraft pair during the IM PA operation using ADS-B Out reports from the Target aircraft. Results for the CSL at San Francisco International Airport are presented and compared with CSLs previously generated using the offline Monte-Carlo simulation method. Additionally, the benefits, drawbacks, and limitations of implementing the new method compared with the offline method are discussed.