A flight tracker is a map with aeroplanes on it. A radar scope is a decision tool. Everything on it exists to answer two questions quickly: are any two aeroplanes going to get too close, and is each one going to arrive at the runway in the right order, at the right height, at the right speed? Here is what you are looking at on ATC Guy — and on the real thing.
The scope is dark so that light means information. The airport sits at or near the centre. Range rings — usually every 5 nautical miles — give distance at a glance: an aeroplane on the third ring is 15 miles out. Nautical miles, not statute; at 180 knots an aeroplane covers 3 NM a minute, which is the arithmetic controllers do in their heads all shift.
Each aeroplane is a small symbol with a short history trail showing where it has just been — the trail's direction and spacing tell you heading and speed before you read a number. Attached to it is the data block: the callsign (BAW123, THY1923), the altitude in hundreds of feet (070 is 7,000 ft), the ground speed, and often the assigned or cleared altitude beside the current one. An arrow or a vertical rate tells you whether it is climbing or descending. On ATC Guy, tapping a data block in LIVE mode reveals the real ADS-B values behind it.
The pink line extending from the runway is the extended centreline — the path aeroplanes must join to land. The goal of approach control is to deliver each arrival onto it, established, at the right altitude and spaced from the one ahead. Where two runways are in use you see two corridors; where Istanbul lands on 34L and 35R at once, both are drawn and each aeroplane is assigned to one.
Two aeroplanes must be either 3 NM apart laterally or 1,000 ft apart vertically (the numbers vary by airspace, but these are the ones ATC Guy uses). The scope shows a violation as an expanding ring and an alert. Behind a heavy aeroplane — an A380, a 777 — the following aircraft needs extra miles because of wake turbulence. On parallel independent runways, aeroplanes established on different localisers may be as close as 1 NM: they are on separate tracks by definition.
Controllers read the scope as a line, not as dots: who is number one, who follows, and how many miles are between them. A good final has even gaps — 3 to 5 miles — with each aeroplane descending on a stable profile. Bunching means someone will have to be turned off or slowed; a gap means a departure can go. The best controllers are barely talking because the line built itself ten minutes ago.
The fastest way to learn to read a scope is to watch a busy one with the answers visible. Open any live radar, pick the runway in use, and follow one arrival from the edge of the sector to touchdown — then take the position and do it yourself.
📡 Open a live radarMore live radars:
Istanbul Airport · Athens International · Amsterdam Schiphol · Zurich Airport · London Heathrow · New York JFK · Tokyo Haneda · Hong Kong International · Dubai International · Madrid Barajas · Atlanta Hartsfield-Jackson · Innsbruck Airport
ATC Guy is a free browser game. Live positions come from community ADS-B receivers (adsb.lol) and update every ~10 seconds. Not for real-world navigation. Contact