runways positioning

[bombardier]

hello to all;

what deternines the positon of runways at airports? is it the weather conditions, the topography around the airport or maybe other airports or what? for example the dover air base runways goes from southeast to northwest and south to north. I might be a off a few degrees on the runways. but I do know the south runway is 01. and why so many airports have the same runway position in degrees. I have not seen any west to east runways. no thats not true, theres 2 airports one in france and one at heathrow in england that I land often that has west and east runway .

any one answers please explain

bombardier

[Webb]

KMIA (Miami) is 92° /272° because that's the direction the wind blows.

[investdude]

The prevailing wind is the primary factor in determining a runway's positioning. A good example of this is the roughly 130 British Commonwealth Air Training Plan (BCAPT) aerodromes that were built in Canada during the Second World War. The wind information they had at that time was very sparse and they couldn't afford to delay construction waiting for better information so what they did was build them as a triangle of 3 runways. By the end of the war they found that, on average, at all of these triangular airports, one runway (both directions) was used about 70% of the time, a second runway was used about 30% of the time and the third runway was virtually never used. By building 3 runways in a triangle, one of those runways would be closer to the prevailing wind than the other two and couldn't be off by more than about 30*

[Fozzer]

San Francisco KSFO is a good example of runways facing in different directions; 2x N-S, 2x E-W....>>>

https://www.airnav.com/airport/KSFO

...but in all my many Sim Flights, over the years, only Runway 28R seems to be the preferred runway for take-off and landings.
No matter which direction I am facing, I am always routed by ATC up the South Bay to 28R for landing, even though it can be a very long detour!

Maybe there's always a Westerly wind blowing over 'Frisco....(as well as all the Fog!).... ...!

Paul...sometimes I ignore ATC!.... ...!

[G.K.]

Not strictly on topic:

My experience has suggested to me that over the last ten years or so wind patterns have changed in my part of the world. Jets streams have on average moved further south in the UK forcing the highs and lows further south. Also the wind has generally been stronger in recent years. I have no idea if this has effected airports.

Going sailing on most weekends, we tend to notice these things. It may be a part of global warming?

[Fozzer]

In my experience, the wind effects have been most noticeable between the purchase of Heinz© Baked Beans, and Sainsbury's own basic version.

The direction depends upon which way I am facing at the time.

The odour is always excruciatingly painful.

Paul....The answer is blowing in the wind... ...!

[C]

British airfields tend towards W-SW for the main runway. However, space is also a factor - certainly in Europe. For example if you look at an airfield such as RAF Leeming the post WW2 main runway is N-S. This is because the WW2 main runway was SW-NE, but has a main road (the A1) at the western end, and obviously it was impractical to re-route it.