About Contrail, the daily flight path game

Contrail is a free daily geography game. Each day you get three rounds, easy, medium and hard. Every round names two to four airports, and you draw the flight path between them on a blank world map with no dots, cities or labels. You score points for putting each airport in the right place and for keeping your line close to the real route. A perfect day is 1000 points: 250 for the easy round, 350 for medium and 400 for hard.

Why do flight paths curve on a map?

Planes fly great circles, the shortest route across a round Earth. Flattened onto a map, those routes bend toward the nearest pole. That's why a flight from San Francisco to Dubai heads north over Canada, Greenland and the Arctic instead of crossing the Atlantic, and why New York to London arcs up past Newfoundland. A straight line on a flat map is almost never the shortest path, and Contrail is a quick daily way to build an intuition for the real shape of the world.

How to play

• Find the first airport on the unlabeled map and draw your route to the next one. Longer rounds have up to four stops.
• Zoom and move the map freely. Drag the ends of your line to fine-tune them. A hint shows one airport for half its points.
• After you submit, a plane flies the real route. Compare your line with everyone else's, check the daily leaderboard, and share your score.
• Want it harder? Turn on Codes only to hide the city names and play with just the airport codes, like LHR, NRT and GRU.

Questions

Is it free? Yes, and there's nothing to install. It works in any browser on phones, tablets and computers.

When is there a new puzzle? Every day at midnight US Eastern time (9pm Pacific), the same moment for everyone.

Is there more? Try Interstate, the sister game, where you trace a US highway from end to end on a blank map of the states.

Ideas, bugs or a question? Email contrailgg@proton.me.