What is TIS and how is it provided?

• A. Traffic Information System; Works through Mode S; informs the pilot of nearby traffic
• B. Terrain Information System; Signals via GPS
• C. Traffic Information System; Receives data from ATC
• D. Total Information System; Onboard radar

Answer: (A)

Traffic Information System is a system that provides you with information about nearby aircraft to help you maintain situational awareness and avoid collisions. It uses the Mode S transponder signals to detect other aircraft in your area and deliver traffic advisories to you, either directly or through integrated cockpit displays. This is why the best description is that it works through Mode S and informs you of nearby traffic.

Terrain Information System would pertain to terrain data, not traffic, and isn’t provided by Mode S in the same sense. The idea of receiving data from ATC is more aligned with TIS-B in some setups, but the coreTraffic Information System concept specifically emphasizes Mode S-based traffic detection and advisories to the pilot. The other terms listed aren’t how TIS is defined.