Azerbaijan Airlines National Aviation Academy Faculty: Air transport Group: 1139aa theme: tcas teacher: Sevda Aliyeva Student: Fariz Safarli

Warnings
Traffic advisory (TA)
Clear of conflict
Resolution advisory (RA)
TCAS II provides the following types of voice announcements:
When a TA is issued, pilots are instructed to begin a visual search for traffic causing the TA. If traffic is visually acquired, pilots are instructed to maintain visual separation from traffic. The training programs also indicate that no horizontal maneuvers should be made solely on the basis of the information displayed on the traffic screen.
When an RA is issued, pilots are expected to respond immediately to the RA. This means that the aircraft must sometimes maneuver against ATC instructions or ignore ATC instructions. In these cases, the controller is no longer responsible for the separation of the aircraft involved in the RA until the conflict is resolved.
TCAS I

• TCAS I is a cheaper but less capable system than the current TCAS II system introduced for general aviation use on airliners. TCAS I systems can track traffic around an aircraft (up to 40 miles away) and provide information on the approximate bearing and altitude of other aircraft. It can also generate a collision warning in the form of a "Traffic Advisory" (TA). The TA alerts the pilot that another aircraft is nearby and announces "Traffic, traficc" but does not offer any suggested remedies; usually the pilot decides what to do with the help of ATC. When a threat is passed, the system announces "Conflict Clear".

TCAS II
TCAS II was the first system introduced in 1989 and is the current generation of TCAS instrument warning used on most commercial airliners. The US Airways 737 was the first aircraft certified with the AlliedBendix (now Honeywell) TCAS II system. It offers all the benefits of TCAS I, but will also offer the pilot direct, audible instructions, known as RA, to avoid danger. Suggestive action can be "corrective" and prompt the pilot to change vertical speed by saying "Descent, descend", "Climb" or "Level off, stop leveling". In contrast, a "preventive" RA may be issued, warning pilots not to deviate from their current vertical speed, announcing "Follow vertical speed" or "Maintain vertical speed, hold". TCAS II systems coordinate their handling recommendations before issuing commands to the pilots, so that if one aircraft is instructed to descend, the other is usually ordered to climb - this is to maximize the distance between the two aircraft.