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# Runway remeaning

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Hello!I use to calculate the Runway remaining distance the formula Ground Speed / Tick 18 adding and write the result to a L:Var every FS cycle and substract the value to previously set runway length. I

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Hi Javier,I may have an alternate method, correct me if my physics is off, as haven't done it for years.Let: L be the distance of the runwaylet

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Sorry let me try that again... ignore the last post.Hi Javier,I may have an alternate method, correct me if my physics is off, as haven't done it for years.Let:L = be the distance of the runwayG = ground speed of the aircraftr = be the radius of the wheel gear (if that value can be found in the aircraft specs)D = distance remaining on runwayThen:D = L - (G * (1/(2*pi*r)))You might have to take the centre of the aircraft as its origin, which might be a problem as there are no wheels there.Therefore you might have to add the extra distance from where the wheels gets its thrust from to the nose of the aircraft.Hope that helps in any way.Adrian

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Sorry let me try that again... ignore the last post.Hi Javier,I may have an alternate method, correct me if my physics is off, as haven't done it for years.Let:L = be the distance of the runwayG = ground speed of the aircraftr = be the radius of the wheel gear (if that value can be found in the aircraft specs)D = distance remaining on runwayThen:D = L - (G * (1/(2*pi*r)))You might have to take the centre of the aircraft as its origin, which might be a problem as there are no wheels there.Therefore you might have to add the extra distance from where the wheels gets its thrust from to the nose of the aircraft.Hope that helps in any way.Adrian
I'm afraid your physics is off.D and L are distances in feet.G is speed in feet/secr is a length in feet and 2*pi*r is the circumference of the wheel in feetYour equation says thatfeet = feet -((feet/sec)/feet)or feet = feet - (1/sec) which is a nonsense.The Runway Distance Remaining (if that's what the OP wants) is the distance in feet from the present position of the aircraft to the end of the runway. It has nothing to do with aircraft speed. Fixed distance-remaining marker boards are often located alongside runways with a single white number on a black background showing the distance remaining in thousands of feet - 5 means 5000 feet remaining.The way it can be calculated is by taking the difference between the aircraft's position and the position of the end of the runway. The former can be obtained directly from FS with some processing. The latter would need to be calculated from the position of the runway its length, its orientation and the aircraft's direction. I don't know how accessible the runway information is from within FS.

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Hello!I use to calculate the Runway remaining distance the formula Ground Speed / Tick 18 adding and write the result to a L:Var every FS cycle and substract the value to previously set runway length. I

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Hi Paul, it may seems weird to use speed to get the aircraft position but read my post below.JavierHello everyone! Excuse the delayed response.I

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Tom is it possible to know the coordinates of the runway threshold? That set of coordinate minus plane coordinates converted to feet could give the remaining distance. Javier
Yes it is. There are GPS variables for a selected runway's coordinates, usually taken from its midpoint. Knowing the bearing of each side and its lenght, using GPS dll's azimuth calcs you can determine the coordinates of both thresholds. Rest is known :( Tom

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