TCAS Operational Performance Assessment


Pilot and Controller Event Questionnaires

About TOPA

TOPA is an FAA-funded program whose focus is the characterization and assessment of TCAS II in the U.S. National Airspace System (NAS). This program is based primarily on data obtained via a monitoring system installed at 20 Mode S radar sites throughout the United States. The TOPA data collection and analyses are conducted by industry organizations that are under contract to the FAA.

Data are automatically collected from these sites whenever a Resolution Advisory (RA) is displayed on an aircraft within the coverage area of the Mode S radar. These data include information on the aircraft receiving the RA, the type of RA issued, and radar track information on nearby aircraft.

Pilot and Controller questionnaires have been developed to obtain data from the individuals involved in a TCAS event. These questionnaires have been used throughout the TCAS monitoring programs to supplement quantitative data collected on TCAS events using ground based radars and TCAS recording devices installed on aircraft. Historically, questionnaires have been completed by hand and then returned to ARINC for review and processing. This web site provides the ability to complete the questionnaires online and have them automatically included in the TOPA analysis database.

All data collected by TOPA are used for TCAS analysis purposes only. The data are not used to support punitive or enforcement actions. All data are de-identified within 45 days to protect the privacy of individuals, organizations, and facilities involved in a specific encounter

Stay Informed.

Register with TOPA and receive email updates regarding the TCAS program. Registration is easy, simply complete the form located here.

Contact Us.

Questions or concerns? Click here to contact us.