How do I use traffic radar or TCAS in a flight simulator?

In a flight simulator, power the avionics, enable AI or multiplayer traffic, set the transponder to altitude-reporting mode, then select TA/RA on the TCAS panel. Use the display range and altitude filter to find nearby aircraft, read their relative altitude and trend, and follow a resolution advisory only when the simulated system commands one.

Traffic radar and TCAS are not the same

In general flight-simulator use, “traffic radar” may describe several systems with different capabilities. TCAS predicts conflicts from transponder traffic; a simulator radar gauge may simply read nearby aircraft from the simulation engine.

A mistake we see constantly is selecting the weather-radar layer and expecting aeroplanes to appear. Select TFC, TRAFFIC or the aircraft's equivalent control instead. Military intercept radar is another separate system and should not be confused with an airline TCAS display.

Legacy simulators often need an additional panel gauge. An FS2004 IVSI and transponder gauge with TCAS mode controls demonstrates an integrated airline-style installation, while an FSX utility-style radar showing surrounding aircraft data behaves more like a general traffic monitor.

How do I set up and use TCAS in a simulator?

1. Supply some traffic. Enable compatible AI or multiplayer aircraft. If the sky is empty, follow our instructions for setting up AI airline traffic in a flight simulator before troubleshooting the display.
2. Power the aircraft systems. Turn on the required electrical buses, avionics and displays. Complex aircraft may also require their normal alignment or initialisation procedure before traffic appears correctly.
3. Activate the transponder and TCAS. Select altitude-reporting mode—usually labelled ALT, ON or an integrated operating mode—then choose TA/RA for full TCAS II operation. Use the aircraft checklist because some models switch modes automatically during take-off and landing.
4. Display the traffic layer. On an airliner this is commonly a traffic overlay on the navigation display or an IVSI/TCAS instrument. Other aircraft place it on a multifunction display, moving map or separate pop-up gauge.
5. Set a useful range and altitude filter. Use a shorter range in terminal airspace and a longer range en route. ABOVE favours traffic above during a climb, BELOW favours lower traffic during descent, and NORM shows the usual band around your altitude. Exact vertical limits vary by system.
6. Watch closure and vertical trend. A target's colour and shape are more significant than distance alone. Do not turn towards or away from a symbol merely because it looks close.

The principal mode choices are STBY, which gives no operational advisories; TA ONLY, which warns about threats without commanding a manoeuvre; and TA/RA, which enables resolution advisories where the aircraft and add-on support TCAS II. Surface targets and some advisories may be suppressed near the ground by design.

How do I read TCAS symbols and altitude numbers?

Most airline-style TCAS displays use shape and colour to show the target's threat level, although older gauges may substitute white for cyan or yellow for amber.

The number beside a classic TCAS symbol normally gives relative altitude in hundreds of feet. For example, +05 means 500 feet above your aircraft, -12 means 1,200 feet below, and 00 means approximately level with you. An up or down arrow indicates a significant climb or descent; the exact trend threshold depends on the implementation.

Some utility radars display absolute altitude, flight level, heading or callsign instead. Check the gauge legend before assuming every altitude label is relative. TCAS threat classification also considers closure time and projected separation, so a nearby diverging aircraft may remain an ordinary diamond while a more distant converging target becomes a TA.

What should I do after a traffic advisory or resolution advisory?

A traffic advisory, often accompanied by “Traffic, traffic”, is an awareness warning rather than a manoeuvre command. Identify the target visually where practical, monitor the display and be ready for an RA; do not make an abrupt vertical or horizontal move solely from the TA.

A resolution advisory gives vertical guidance such as CLIMB, DESCEND, ADJUST VERTICAL SPEED or MONITOR VERTICAL SPEED. On displays with an RA-capable vertical-speed indicator, keep the needle out of the red prohibited area and aim for the green commanded area when one is shown.

For conventional airliner simulation, hand-fly the vertical response if the autopilot cannot follow the RA, and do not invent a lateral turn from the target's bearing. Some advanced aircraft models provide automatic RA response, so use that aircraft's documented procedure rather than fighting its automation. After CLEAR OF CONFLICT, return smoothly to the assigned flight path and advise simulated ATC if the ATC system supports such reports.

Why is my traffic radar or TCAS display blank?

A blank display is usually caused by the traffic source, operating mode or display layer rather than a failed gauge. Check these items in order:

• No compatible traffic exists: confirm that AI is enabled or that multiplayer aircraft are being injected into the simulator. Some network traffic never reaches third-party gauges.
• The transponder is in standby: select altitude-reporting and an active TCAS mode. Changing the squawk code alone does not activate TCAS.
• The traffic overlay is hidden: press the relevant traffic button on the correct navigation display or multifunction display. Selecting weather radar will not show TCAS targets.
• The range or altitude filter excludes the target: increase the range and return the filter to its normal setting for testing.
• The panel lacks power or position data: verify electrical power, avionics and any required aircraft-system initialisation.
• The aircraft does not model functional TCAS: some cockpit displays and switches are decorative, while others show traffic but do not calculate RAs.
• The target is not considered a threat: nearby traffic may produce no TA or RA if it is diverging, vertically separated or subject to low-altitude inhibition.

The quickest diagnostic sequence is traffic source, electrical power, transponder mode, traffic overlay, range and filter, then aircraft support. Test with a known airborne AI aircraft; parked airport traffic may be filtered deliberately and is a poor test of TCAS operation.