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When ATC gives you headings to fly, do they consider wind correction? In theory they should because they call it a heading and not a track, but do they? After all, the heading they want you to fly depends on wind direction and airspeed.

Or do they actually mean track instead of heading?

Lnafziger
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Philippe Leybaert
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2 Answers2

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When the controller says heading, he means heading. So if he wants you to go into a specific direction, he will take wind into account. The reason for issuing heading are:

  1. Every aircraft can fly it, because a compass is fitted on every aircraft. Track keeping requires more sophisticated avionics.
  2. If two aircraft fly adjacent to each other, the wind will offset them by the same amount and therefore separation is assured.

Quite often a controller will ask you to report your present heading prior to instructing a one so he can make more accurate adjustments to your course, especially if you were under own navigation before being vectored.

With Mode S radars and the right equipment in the aircraft, the current heading can be downloaded from the avionics without the pilot being aware of it.

DeltaLima
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    #2 is not entirely true. When there's a significant crosswind, an aircraft flying a heading of 200 at 100kts will have a different track than an aircraft flying the same heading at 200kts – Philippe Leybaert Dec 18 '13 at 17:08
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    That is true, but in such a situation the separation issue will be resolved longitudinally before it becomes a problem laterally. – DeltaLima Dec 18 '13 at 17:13
  • Still, I wonder if a controller will provide the correct heading to a light airplane flying at 90kts with a 60kt crosswind (which is not that uncommon above 3000ft) – Philippe Leybaert Dec 18 '13 at 17:18
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    They'll certainly try! I've never heard a controller provide a track to be flown. – egid Dec 18 '13 at 17:20
  • @PhilippeLeybaert -- (not sure why I just happened to stumble across this) -- re your comment-- well, it's complicated. Yes, the ground tracks are different. Yet from the airmass reference frame the direction of travel is the same-- so it is absolutely valid to say that separation is assured. There is no possibility that the aircraft will ever get closer together than the shortest distance you could measure between each of their air track lines, meaning an imaginary line drawn from nose to tail of each individual airplane, and extended infinitely far in each direction, fore and aft. – quiet flyer Mar 01 '23 at 14:53
  • The "air track" line of one plane is parallel to the air track line of the other, and the shortest distance between those two lines is the closest the planes could ever get, even though the ground track lines are not parallel. (A bit of mind-bender...) – quiet flyer Mar 01 '23 at 14:55
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ATC gives headings, and they mean heading; any wind correction is included in the controller's planning. You'll occasionally hear controllers adjust headings ("turn 10 degrees left") because the wind exceeded their expectations.

egid
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