Why do planes fly over Greenland when crossing the Atlantic?

Answer 1

The shortest route is around the world....its curved you know.

Answer 2

There are a couple of factors here. The route is nick named the "blue spruce route". This route is for aircraft the a. Do not have the range to make a pass across the Atlantic and there fore must stop to refuel b. If the aircraft is not equipped with dual HF's (communication system using lower frequencies for longer distance use c. or can also be an option for someone who does not have a comfort level with flying long distances over an ocean.

The third sounds silly, but I have a customer who's aircraft I have worked with who just does not want to fly over large bodies of water... due to if there was a problem... there is no place to land.

Answer 3

It's for safety reasons. If the Aircraft systems or an engine were to fail, then there is a much better chance of redirecting to an airfield if the aircraft is going over land than if it was over the centre of the atlantic ocean.

Also, it really is the shortest route. Get a globe and put your fingers on the UK and America. The shortest route takes you over greenland. It's difficult to picture without a globe.

Answer 4

Somtimes you do and sometimes you don't. Actually, I have rarely crossed over Greenland and I have made about 250 transoceanic crossings, about 100 of which I commanded.

You receive your oceanic clearance before you "coast out". They can clear you onto a specific North Atlantic Track (NAT) which change every day for wind optimization or they can clear you random routing. Their rules are that they are supposed to clear you coordinates that will require you to check back in with them at less than one hour intervals. Basically, they are going to clear you a specific latitude for each ten degrees of longitude. For an example, they may clear you (and I didn't look at a globe when I made these coordinates up):

42 degrees N, 10 degrees W
40 degrees N, 20 degrees W
41 degrees N, 30 degrees W
41 degrees N, 40 degrees W
42 degrees N, 50 degrees W
41 degrees N, 60 degrees W
(your coast in point, wherever that may be)
(then they give you an initial assigned altitude)
(a primary HF frequency and a backup HF frequency)

This is an example of a random routing clearance, after receiving such a clearance you would then read it back to them, item by item.

Some of the theories above are both correct and incorrect, a great circle does decrease the distance traveled versus a rhumb line, however, the winds play a far greater effect than flying a great circle vs. a rhumb line. The NATs change every single day for wind optimization. You will fly great circles between each individual set of coordinates in your clearance, regardless of whether they are part of a NAT or random routing. However, the individual sets of coordinates aren't designed to give you a great circle routing all the way across the ocean.

After passing individual set of coordinates along each interval of ten degrees of longitude in your NAT or random routing, you have to contact the appropriate agency, whether it be Gander, Shanwick, Santa Maria (which are Atlantic ocean agencies), or the appropriate agency for whatever ocean you are crossing, and tell them the time that you passed over that particular lat/long, your altitude, your ETA at the next set of lat/long in your clearance, and then you give them the next set of lat/long after that but without an ETA. You do this over a high frequency radio (which have global range) or via ACARS.

Answer 5

Routes are determined by 2 factors, shortest direction, and upper level winds. Usually, the shortest direction and prevailing winds take the routes to europe over Greenland, but not always. I have flown many times south of Greenland, (in both directions) due to a shift in the winds.

Answer 6

Take a piece of string and hold it between any two locations over a GLOBE of the Earth. You will see a Great Circle route that may surprise you if your view of the world is from flat maps.

Answer 7

It's called A Great Circle. Shortest distance between two points on the globe.

Answer 8

Due to the curvature of the earth it is the shortest route, further planes that haven't got ETOPS certification have to fly close to land incase of emergency.

Answer 9

Shortest route around a globe, between London and Canada mostly.

Answer 10

Because we live on a globe. the shortest route between two points is an arc not a straight line!
I have never really understood why myself so I cannot explain it properly but I do accept it's veracity.

Answer 11

Because it's along the shortest route to Northern Europe. It also provides access to an emergency landing place should it ever be needed.