nonthreatening/nonhostile; TOI was identified based on specific and credible intelligence that was later determined to be invalid or unreliable; or displayed data is identified and characterized as invalid . 

## TRAFFIC- 

a. A term used by a controller to transfer radar identification of an aircraft to another controller for the purpose of coordinating separation action. Traffic is normally issued: 

1. In response to a handoff or point out, 

2. In anticipation of a handoff or point out, or 

3. In conjunction with a request for control of an aircraft. 

b. A term used by ATC to refer to one or more aircraft. 

TRAFFIC ADVISORIES- Advisories issued to alert pilots to other known or observed air traffic which may be in such proximity to the position or intended route of flight of their aircraft to warrant their attention. Such advisories may be based on: 

a. Visual observation. 

b. Observation of radar identified and nonidenti- fied aircraft targets on an ATC radar display, or 

c. Verbal reports from pilots or other facilities. 

Note 1: The word “traffic” followed by additional information, if known, is used to provide such advisories; e.g., “Traffic, 2 o'clock, one zero miles, southbound, eight thousand.” 

Note 2: Traffic advisory service will be provided to the extent possible depending on higher priority duties of the controller or other limitations; e.g., radar limitations, volume of traffic, frequency congestion, or controller workload. Radar/ nonradar traffic advisories do not relieve the pilot of his/her responsibility to see and avoid other aircraft. Pilots are cautioned that there are many times when the controller is not able to give traffic advisories concerning all traffic in the aircraft's proximity; in other words, when a pilot requests or is receiving traffic advisories, he/she should not assume that all traffic will be issued. 

(Refer to AIM.) 

## TRAFFIC ALERT (aircraft call sign), TURN (left/right) IMMEDIATELY, (climb/descend) AND MAINTAIN (altitude). 

(See SAFETY ALERT.) 

TRAFFIC ALERT AND COLLISION AVOID- ANCE SYSTEM (TCAS)- An airborne collision 

avoidance system based on radar beacon signals which operates independent of ground-based equip- ment. TCAS-I generates traffic advisories only. TCAS-II generates traffic advisories, and resolution (collision avoidance) advisories in the vertical plane. 

## TRAFFIC INFORMATION - (See TRAFFIC ADVISORIES.) 

TRAFFIC INFORMATION SERVICE-BROAD- CAST (TIS-B)- The broadcast of ATC derived traffic information to ADS-B equipped (1090ES or UAT) aircraft. The source of this traffic information is derived from ground-based air traffic surveillance sensors, typically from radar targets. TIS-B service will be available throughout the NAS where there are both adequate surveillance coverage (radar) and adequate broadcast coverage from ADS-B ground stations. Loss of TIS-B will occur when an aircraft enters an area not covered by the GBT network. If this occurs in an area with adequate surveillance coverage (radar), nearby aircraft that remain within the adequate broadcast coverage (ADS-B) area will view the first aircraft. TIS-B may continue when an aircraft enters an area with inadequate surveillance coverage (radar); nearby aircraft that remain within the adequate broadcast coverage (ADS-B) area will not view the first aircraft. 

TRAFFIC IN SIGHT- Used by pilots to inform a controller that previously issued traffic is in sight. 

(See NEGATIVE CONTACT.) 

(See TRAFFIC ADVISORIES.) 

TRAFFIC MANAGEMENT PROGRAM ALERT- A term used in a Notice to Airmen (NOTAM) issued in conjunction with a special traffic management program to alert pilots to the existence of the program and to refer them to a special traffic management program advisory message for program details. The contraction TMPA is used in NOTAM text. 

TRAFFIC MANAGEMENT UNIT- The entity in ARTCCs and designated terminals directly involved in the active management of facility traffic. Usually under the direct supervision of an assistant manager for traffic management. 

TRAFFIC NO FACTOR- Indicates that the traffic described in a previously issued traffic advisory is no factor. 

TRAFFIC NO LONGER OBSERVED- Indicates that the traffic described in a previously issued traffic advisory is no longer depicted on radar, but may still be a factor. 

