Several years ago, I saw a set 4-5 of con-trails converging at nearly the same time and height. They were each executing large turns (90 to 300 degrees) over the same space, starting from various directions, and leaving from various. This took over/near Kansas City Int'l (MCI).

Sadly, I failed to take a pic.

Recently, I got another pic! Same location, apparent altitude, same high-degree turn, but only one con-trail.

What would cause a plane (or 4 planes!) to make such large turns? Surely diverting to a new airport would only cause a minor deviation from cruising alt.

Both times I was 17.5 mi south of MCI. I think I've probability mis-characterised their altitude.


  • $\begingroup$ Once in a while I also see something very very similar to that over my head and they are from jet fighters... training or just having fun :) $\endgroup$
    – sophit
    Nov 25, 2022 at 12:34
  • $\begingroup$ Can you give us an idea of where this is? There may an area they are not allowed to overfly, and they have to make this little "detour". Or it may be the junction between two airways which avoid that area. For instance North of Las Vegas there's a large area with no airways, so the airways on the sides have pretty large angles between them. $\endgroup$
    – jcaron
    Nov 25, 2022 at 13:24
  • $\begingroup$ Sorry, I missed that you wrote this was near MCI. Can you let us know the direction you were facing when you took the picture, and possibly where relative to MCI you were? Also, did you check on flightradar24 or flightaware for any flights around that date/time? $\endgroup$
    – jcaron
    Nov 25, 2022 at 13:56
  • $\begingroup$ Both times I saw this, I was 17.5 mi due S of MCI. I.e., facing north. I'm probably wrong about them being at cruising alt. $\endgroup$ Nov 26, 2022 at 1:42
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    $\begingroup$ If you look at the airways in the area on skyvector.com you'll see it could be an aircraft coming from J80 or J26 going to J41 for instance. Depending on where they are coming from/going to it's probably not an ideal routing, but there could be some issue on the more direct routing that would have sent them this way. Next time you see this, look up flightradar24 (you can install the app on your phone) to see what flight it is, it could help explain exactly why they are doing this. Note that it is quite possible it happens very often but you only notice it when they leave contrails. $\endgroup$
    – jcaron
    Nov 26, 2022 at 14:41

2 Answers 2


They were probably "stacked up" in a holding pattern while waiting for permission to land at a busy airport. This is a common occurrence and the flying maps that pilots use will have a "racetrack" marked up near the destination airport. If things are too busy on the ground to manage incoming traffic, the air traffic controller will instruct the pilot of an arriving plane to divert and "hold as published", which means proceed to the racetrack and go round in circles until you get the all-clear instruction.

Each plane in the holding pattern is assigned their own altitude to circle in, and the ATC will pluck the bottom-most plane out of the stack and clear them to land. Then all the other planes that are stacked up are reassigned the next-lower altitude to hold on and the whole stack "drops" down one level.

This puts the plane that has been holding the longest at the bottom of the stack, and the newest plane to arrive is inserted into the topmost level in the stack.

ADDED IN EDIT: As pointed out by others here, course changes like the one pictured are often performed by military aircraft, performing maneuvers on training flights. You can pick these out from the ground by noting that such flights do not generally follow the airway patterns for your area. For example, in western Oregon between Eugene and Portland, all the commercial flights high enough to pull contrails follow north-south lines. A jet at cruise that flies overhead here on an east-west track is therefore not a commercial flight because there are no commercial destinations along that line.

BTW once on a flight between Portland and the SFO bay area, our pilot announced that ATC wanted us to arrive 5 minutes or so later than scheduled and in response the pilot made a slow right circle, at cruise. This was approximately over the Oregon-California border. I do not know how often passenger jets get instructed to "hold at cruise" like this.

  • 2
    $\begingroup$ I've heard of racetracks, but I've never heard of them being at cruising altitude before. Can that be right? Do planes really circle up to 200 miles from the airport? $\endgroup$
    – Michael
    Nov 25, 2022 at 3:26
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    $\begingroup$ @Harper, This is routinely done every day. In an ATC's training, they are required to drop a stack of five planes or more sequentially, by memory, in case their radar displays fail and they have to manage the racetrack by hand. $\endgroup$ Nov 25, 2022 at 8:38
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    $\begingroup$ @Harper-ReinstateMonica You can be sure that it's a solved problem. Basically any flaw in the system, that you can think of, if you aren't heavily involved in the matter, has been dealt with decades ago. $\endgroup$
    – Dakkaron
    Nov 25, 2022 at 8:58
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    $\begingroup$ This answer is accurate in describing holding, but I’m not convinced it’s applicable to the photo. All I see is a course change. $\endgroup$ Nov 25, 2022 at 16:53
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    $\begingroup$ I can’t imagine a stack ever forming at MCI. It’s just not that busy. $\endgroup$
    – TomMcW
    Nov 27, 2022 at 0:19

In my experience as an observer, aircraft performing large turns (greater than say a simple 45-degree "bend" in the flight path) up at the contrail level have a greater-than-average chance of being military rather than commercial aircraft. Always a good reason to break out the binoculars and see what aircraft is leaving the trail.

From your description, it's difficult to tell whether any of the aircraft were actually flying together in close proximity, or not. If so, aerial refueling comes to mind as a possible explanation. But one can imagine many other scenarios, including various training exercises, where one or more military aircraft would follow a flight path that was configured to prioritize objectives other than simply transiting from point A to point B as efficiently as possible.

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    $\begingroup$ The usual objection about not invalidating existing answers notwithstanding, perhaps the question could be modified to address the last paragraph of this answer -- $\endgroup$ Nov 25, 2022 at 11:44
  • $\begingroup$ Both times I was 17.5 mi south of MCI. I think I've probability mis-characterised their altitude. No known military activity that I know of there. $\endgroup$ Nov 26, 2022 at 1:52
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    $\begingroup$ A tanker on an aerial refueling mission seems like the most probable explanation... especially for the not-photographed case of several contrails doing similar things... one or two tankers & multiple receivers, all following similar tracks. $\endgroup$
    – Ralph J
    Nov 26, 2022 at 5:40
  • $\begingroup$ Edited question to remove mention of plan(es) being at cruising altitude. I do not the altitude. $\endgroup$ Nov 27, 2022 at 4:16
  • $\begingroup$ @user1745937 -- to me the edit doesn't really change anything, and wouldn't have affected my answer, the point is that they were high enough to make contrails, which is pretty much only going to happen up at the levels that a jet would consider using for long-range cruising flight, or at least somewhere kind of close to that. (Google "at what altitude do contrails form"). And to the best of my knowledge, the "holds" mentioned in other answers are not routinely executed that high, though one answer does detail one specific exception, a single circle performed to delay the arrival. $\endgroup$ Nov 27, 2022 at 14:26

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