Are there any 'straight-line' flights?
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Are there any 'straight-line' flights?
As in are there any commercial flightpaths were you stay on the same heading the entire flight and don't have to change heading except for slight corrections on landing for example?
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Are there any 'straight-line' flights?
No heading change...that would mean either pure East/west along the equator or North-South. Any other great circle will result in heading changes. Small changes on short flights, very noticeable on long range.
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In theory yes, in practice, no.
To begin with even runway 12 will have a 10 degree direction span (roughly), so the likelyhood of the tracks being exactly the same is very small.
Also local noise abatement will most likely mean there will be some extended routings at low level over residential areas.
There will be some flight that have very few heading changes, but absolutely no change of track seems very unlikely.
To begin with even runway 12 will have a 10 degree direction span (roughly), so the likelyhood of the tracks being exactly the same is very small.
Also local noise abatement will most likely mean there will be some extended routings at low level over residential areas.
There will be some flight that have very few heading changes, but absolutely no change of track seems very unlikely.
As in are there any commercial flightpaths were you stay on the same heading the entire flight and don't have to change heading except for slight corrections on landing for example?
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Just wondering really, no real reason.
Came from a discussion I was having with someone about why a transatlantic flights seems to go in a curve, rather than the straight line they were expecting.
Came from a discussion I was having with someone about why a transatlantic flights seems to go in a curve, rather than the straight line they were expecting.
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Because you're looking at a 2D map which is a 2D representation of a 3D planet. If you read up on chart projections and great circle routes you will find the answer, but basically, that circle is the shortest route. Your map is making it appear longer because the map isn't a uniform scale (once again, 2D vs 3D).
Put another way, the Earth is a sphere. (Technically, it's an oblate spheroid - slightly squashed at the poles.)
The most direct line from a point to any other point is a line that cuts through the entire diameter of the Earth that intersects the two points. (A great circle.)
Except when flying along the equator, or in a direct line between the geographic poles (both of these are also great circles), there is a continually changing heading required to maintain the line.
That's without route structures, holding patterns etc.
The most direct line from a point to any other point is a line that cuts through the entire diameter of the Earth that intersects the two points. (A great circle.)
Except when flying along the equator, or in a direct line between the geographic poles (both of these are also great circles), there is a continually changing heading required to maintain the line.
That's without route structures, holding patterns etc.
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I imagine on shorter flights it's more likely to go in a "straight line". For example, I flew EDI-BLL a few years ago, looking at the GC Map that shows an almost perfectly straight line as the airports lie on roughly the same latitude. I remember the flight barely had to turn after leaving EDI, not until we had to circle once at BLL before landing.
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No, I know why the flight paths seem to curve, but she didn't and I was explaining that to her. Which then got me wondering if there are any flights that do actually go in a straight line in the real world where the runways line up so perfectly that very little course change is needed.
EDI Local, that's the kind of thing I mean.
EDI Local, that's the kind of thing I mean.
Although it is a great circle route with all that entails i dont think the guys up front have to touch the heading select button much aboard the BA 2233 London Gatwick 26 L to Kindley field Bermuda Rwy31 just keep heading approx SE and you end up with a nice 30 odd degree intercept for landing at Bermuda.
Of course it only works when the jetstream is in a normal location-too strong and you can end up going over iceland
Of course it only works when the jetstream is in a normal location-too strong and you can end up going over iceland
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Surely most long haul flights do not use pure great circle routes but instead follow minimum time tracks wherever possible even though the distance by be greater. Winds aloft, weather and available slots all play a part.
I think for long haul, especially Oceanic, the route starts out as a great circle and then as you rightly say gets modified for winds aloft or ETOPS factors.
I flew the Bermuda route many many times and in summer regularly got close to a simple great circle-winter with the N Atlantic winds was another story and as you point out the minimum time path can seemingly take you a very very long way from a a direct path when heading west
I flew the Bermuda route many many times and in summer regularly got close to a simple great circle-winter with the N Atlantic winds was another story and as you point out the minimum time path can seemingly take you a very very long way from a a direct path when heading west
