The Plane Highway in the Sky

 If you’ve ever looked at a flight tracker sometime around 10 or 11 pm eastern, you might have noticed something—perfect lines of planes stretching all the way to Europe. These are just some of the over 2,000 daily flights that cross the Northern Atlantic. With so many flights, there just has to be organization. This is the most direct route from New York to London. You may think it’s this, a straight line, but that straight line isn’t actually a straight line. This curved line is a straight line because, despite what some may think, the earth is curved. From New York to London the curve you see on a flat map isn’t too extreme, but in the case of a longer flight, such as from New York to Bangkok, the most direct route is not this, but this—straight over the North Pole. It makes more since if you look at a north-pole oriented map. If you draw the most direct route between Atlanta and London, you’ll see that it passes over every major east coast international airport. That means that planes from Atlanta to Europe travel on the exact same route as planes from Charlotte, Washington, Baltimore, Philadelphia, New York and Boston. On top of that, all these transatlantic planes typically leave between 6-8 pm Eastern to time their arrival for early morning in Europe. This means that there are potentially hundreds of planes all going the exact same route at the exact same time. The North Atlantic also has something known as the Jet Stream. These easterly winds average around 110 mph and if planes fly in them, they can cut hours of their travel time, however, the winds are only strongest in a line three miles high (5 km) and 100 miles (160 km) wide. That further concentrates the flights. On average, an eastbound transatlantic flight from New York to London takes about 6 hours and 15 minutes. Coming back against the jet stream, the same flight takes over 7 hours. Sometimes, the winds can be even more active such as on January 8th, 2015 when British Airways flight 114 flew from New York to London in only 5 hours and 16 minutes—a new record for a commercial subsonic plane. On that day, the jet stream was blowing over 200 mph (320 km/h) and the Boeing 777 reached a speed of 745 mph (1200 km/h) —only 16 mph (25 km/h) below the sound barrier. So when winds can cut an hour off a flight and a 777 burns 2,700 gallons (10,200 liters) of fuel per hour and jet fuel costs $1.89 per gallon, that’s a $5,103 difference between being in the right, and the wrong winds. Hopefully you now see why this is important. So there are all these planes that are flying the exact same route, but usually that’s no problem. The busiest route in North America, New York to Chicago, sees over 100 flights per day leaving as frequently as every five minutes during the morning and evening rush and these planes just fly the most efficient route. Before the flight, route planners file a plan with air traffic control and during the flight, they’re just directed by air traffic control in a way that keeps them 5 nautical miles from other planes. The difference between New York to Chicago and New York to London is that, over the North Atlantic, there is no radar. You see, radar only extends about 250 miles offshore. Transatlantic planes can be more than a thousand miles from shore. That’s why every morning, the route planners at Gander Air Traffic Control Center in Gander, Newfoundland publish the days North Atlantic Tracks. The night before, every airline that will fly across the atlantic the following day sends Gander a preferred route message indicating what they think the best route will be. For the most part, Gander center follows these requests and creates a set of 10 or so routes. These tracks attempt to get the most amount of planes on the most efficient route to Europe. The tracks are labeled: Zulu being the southernmost route, Yankee being the second southernmost, then Xray, then Whisky, and so on and so forth. Here’s how a flight on the tracks works, and I’ll warn you, this is when the post gets technical. Let’s say we’re going from New York to Paris. Around half an hour before scheduled departure, the captain talks to normal air traffic control to request clearance for the route up to around Newfoundland, Canada. In most cases clearance is given, and soon after we’ll take off. ABOUT when the plane crosses the Gulf of St Lawrence, the pilot will request the North Atlantic Track that he or she desires. Here’s today’s message describing the day’s routes over the Atlantic. After looking over this, the pilot decides to request track Whisky. That means that, at least for now, we’ll head towards the RAFIN waypoint, our oceanic entry point. Waypoints are fixed spots that are used for flight navigation. These are much easier for Air Traffic Control to communicate to pilots than map coordinates when speaking over radio. Occasionally you’ll see some creatively named waypoints. Just north of Lebanon, New Hampshire are HAMMM, BURGR, and FRYYS. On approach to Kansas City Airport there’s SPICY BARBQ TERKY SMOKE RIBBS. Boston has two waypoints in support of their sports teams, the KUBBS and BEARS. Some waypoint names are more somber. On the northern approach route to Washington Regan National Airport, just miles away from where a plane hit the Pentagon on 9/11, the waypoints read WEEEE WLLLL NEVVR FORGT SEP11. Since the North Atlantic Tracks change every day, the MOTAM just gives entry and exit waypoints, and then coordinates for the route in between. Since the track coordinates are pre-programed into the autopilot before take-off, there’s no reason to name them as waypoints since they won’t be given over radio. In the case of this flight, we’re REQUESTING track WHISKY and, more than likely, Gander Control Center will give permission, although, sometimes they’ll tell us to take a different track, usually because we’re closer to another plane than the minimum separation distance. Since it’s much more difficult to know where planes are over the North Atlantic, THEY’RE required to be 15 minutes separated—about 140 miles—rather than the normal 5 miles in areas with radar coverage. Assuming we’re granted clearance, we’ll head towards RAFIN waypoint and make sure that our satellite communication systems are working, then we’ll check to see if the High Frequency Radio is working—a backup in case other communications go down. Minutes later, just after passing RAFIN waypoint, the controller will say “radar services terminated, have a good night,” and then we’re on our own. All the North Atlantic Tracks are preloaded onto autopilot, so there’s nothing really to do except wait. When we we hit 30 west, we enter the Shanwick airspace approaching Western Europe. We switch our radios to Shanwick’s frequency, then fly a few more hours to our Oceanic Exit Point—GUNSO waypoint—meaning we’ve successfully traversed the Northern Atlantic.