If the plane is below 100 meters in altitude, the trail will be white. If it is above 100 meters, the trail will yellow, then green, then above 2500 meters it will become light blue, then dark blue, purple and for the highest altitude it will be red.

Excellent question! On flight tracking apps and websites like Flightradar24, FlightAware, and ADSBexchange, the color of an aircraft’s trail or icon primarily indicates its ground speed (how fast it is moving over the ground).

Here’s a breakdown of the most common color schemes, using Flightradar24 as the primary example, with notes on other platforms.

Primary Meaning: Ground Speed

The spectrum from red to yellow to light blue represents increasing speed.

• White / Grey: Typically used for aircraft that are on the ground (taxiing, parked) or for which no reliable speed data is available.
• Light Blue / Cyan: Slowest airborne speed. Usually indicates an aircraft traveling below 100 knots (115 mph / 185 km/h). This often includes:
  • Helicopters
  • Small general aviation planes (e.g., Cessnas)
  • Aircraft in a holding pattern or on final approach
• Green: Moderate speed. Generally between 100 and 200 knots. Common for:
  • Regional turboprops (e.g., ATR 72, Dash 8)
  • Aircraft during climb-out after takeoff or initial descent
• Yellow: Fast speed. Typically between 200 and 300 knots. This often includes:
  • Jet airliners at lower altitudes where speed restrictions apply
  • Aircraft in the middle phases of climb or descent
• Orange: High speed. Usually between 300 and 400 knots. Common for:
  • Jet airliners at higher altitudes, but not yet at cruising speed