Indicators of Caution
Communication of an on-track incident has advanced since the days when a lone yellow flag would signify the change in track condition to drivers. Today, NTT IndyCar Series competitors have multiple indicators of caution communicating the continually changing track condition during a race.
Radio Communication: As soon as a caution occurs, race control radios the change in track condition to team members and sanctioning body personnel. Immediately, a team’s spotter on top of the grandstand or race strategist on the pit box relays the information to the driver via two-way radio.
Yellow Flag: A flagman located on the starter’s stand displays various flags to communicate the track condition to the drivers. As soon as a caution is called by race control, the flagman waves the yellow flag. Corner workers at road/street course events also display the yellow flag during a full-course or local caution (waving flag at a particular corner).
Track Condition Radio: All cars are required to carry INDYCAR’s track condition radio system. When a full-course caution occurs, race control sends a signal to the car that activates a yellow light in the cockpit alerting the driver to the track condition. Additionally, each spotter on top of the grandstand carries a pager connected to the track condition radio system. When the light system is activated, the spotters’ pagers vibrate, indicating a caution.
Track Light: Each track provides green and/or yellow lights around the outside retaining walls adjacent to the catch fence. When a caution occurs, race control activates a change in lights (green lights off and/or yellow lights flashing) at every location around the track.
Attenuator Light: A road-course rain light is mounted on the attenuator located on the rear of each car. The rain light doubles as a safety light at all tracks. Similar to track condition radio, race control activates the flashing safety light on the attenuator, indicating a caution so that drivers can see the flashing attenuator light on cars in front of them.