Archived

This topic is now archived and is closed to further replies.

Guest dakrisht

Simple Active Runway Q (LAX)

Recommended Posts

What do I need to do to make the Active Runways always be 24L & 25R and 24L & 24R for Los Angeles International (KLAX)???One of the things I never understood was how in all these years and different versions of FSX, MS hasn't learned that at KLAX Runways 07 & 06 are rarely used. LOL.A quick tip is greatly appreciated...(p.s. I've flown into LAX via IFR from the East and even told ATC to change my approach to 24R, and LAX tower still had me go to Runway 07!!)

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

If you create a Westerly wind, then you will get 24L/R or 25L/R. If there is no wind, then FS seems to default to the other end of the runways. I know of no way to change that default. R-

Share this post


Link to post
Share on other sites
What do I need to do to make the Active Runways always be 24L & 25R and 24L & 24R for Los Angeles International (KLAX)???One of the things I never understood was how in all these years and different versions of FSX, MS hasn't learned that at KLAX Runways 07 & 06 are rarely used. LOL.A quick tip is greatly appreciated...(p.s. I've flown into LAX via IFR from the East and even told ATC to change my approach to 24R, and LAX tower still had me go to Runway 07!!)
There is no quick tip since FS9/FSX selects runways based on a complex scoring system. MS does not have to learn what runways are used rarely since this is not a responsibility placed on MS.It is not the decision of MS to close a runway end but the descision is made by the Airport Authority. MS follows what the Airport Authority publishes as active runway useage regardless of rarity. There are many stock airports in the default database that MS closed one end of a runway. MS is not going to close one end as you suggest for KLAX since KLAX says the 06/07's are active runways and can be used when required. KLAX also has ILS's for all 06/07 runways which also includes published ILS and RNAV(gps) approach code. If you the users of FS want to close a runway end then you must do it using the same rules that MS has always used to accomplish this by lowering the active runway score to as close to zero as possible..Since KLAX list the runways as 06/24's and 07/25's you must reverse the Primary Number of 06/07 to 24/25. Now the runways will list as 24/06's and 25/07's which decreases the score by 10000 points for the 06/07's.When that is done you change the runway headings so the new Primary 24/25's list as 263 degrees.Change the Start Locations to coincide with the runway reverse number change.Change the 8 ILS headings and freq's to coincide with the runway reverse number change.Once you have the runway numbers and all associated data reversed delete the 06/07 Start Locations (lowers the selection score)Close for Takeoff and Landing the 06/07 runways (lowers the selection score) Open up the approach code in the FS database and copy out all approaches and then delete the approach code for all 06/07 runways and using the Blocking Attribute XML statement add DeleteAllApproaches ="TRUE" (lowers the selection score).You have now done exactly as MS has been doing for years to create a differential by lowering the Active runway selection score to a very low number for the 06/07 runways in respect to the 24/25 runways. FS/ATC will now use the 24/25's as the primary runway selection in all kinds of weather and winds (winds less then gail force when airport is VMC).The ILS's for runways 06/07 cannot be deleted but are not a factor in the scoring process since they are only for a User Plane to lock on to the beams for horizontal alignment and vertical descent profiles based on a Glide Slope for a properly slotted Glide Path. ATC does not recognize any ILS which is owned by the runway so it does not have any affect on lowering the active selection runway scores.

Share this post


Link to post
Share on other sites
If you create a Westerly wind, then you will get 24L/R or 25L/R. If there is no wind, then FS seems to default to the other end of the runways. I know of no way to change that default. R-
Thanks, that did the trick...

Share this post


Link to post
Share on other sites
What do I need to do to make the Active Runways always be 24L & 25R and 24L & 24R for Los Angeles International (KLAX)???One of the things I never understood was how in all these years and different versions of FSX, MS hasn't learned that at KLAX Runways 07 & 06 are rarely used. LOL.A quick tip is greatly appreciated...(p.s. I've flown into LAX via IFR from the East and even told ATC to change my approach to 24R, and LAX tower still had me go to Runway 07!!)
IFAIK, the rules that FS uses for active runways are based on"1. First give priority to ILS equipped runways (would rank any non-ILS runways lower than those with ILS, regardless of length or any other criteria).2. Look for the longest runways with the above priorities being established, regardless of direction.3. If 1. and 2. above yield reciprocal runways (i.e. both reciprocal runways have ILS, and both of course are the same length if there is no displaced threshold at one end), then select the lower digit (i.e. 08 takes precedence over it's reciprocal 26).You note that you have tried configuring the ATC to land on 25 but it still gives you 07. Please note that there are 2 phases to each instrument procedure in FS, the approach (the first thing you could change) then the landing runway. You must choose both of them, otherwise you will be given a 25 approach and a clearance to "circle-to-land" on 07, which defeats the entire purpose. Remember, you are playing a computer game.Bruce.

Share this post


Link to post
Share on other sites
IFAIK, the rules that FS uses for active runways are based on"snip-------1. First give priority to ILS equipped runways (would rank any non-ILS runways lower than those with ILS, regardless of length or any other criteria).2. Look for the longest runways with the above priorities being established, regardless of direction.3. If 1. and 2. above yield reciprocal runways (i.e. both reciprocal runways have ILS, and both of course are the same length if there is no displaced threshold at one end), then select the lower digit (i.e. 08 takes precedence over it's reciprocal 26).Bruce.
Bruce There is a whole lot more to the rules then what a visual shows Contrary to popular belief No 1. has nothing to do with runway selection. You can add ILS's to any runway and that does not give priority over a non ILS runway. In fact a non-ILS runway can have an additional 12 more approach types that are a factor when airport weather is IMC. The ILS is for the User Airplane only so a Pilot can track the Loc and GS. The ATC Engine could care less about a ILS runway. The ATC Engine when assignmenyt of runway is looked at works with the ARINC 424 written XML approach code compiled to a bgl and then passed to the various Engines by way of the .dll files. Add a ILS to any runway and ATC still sees it as a visual runway. If the runway had a higher priority just because of a ILS then ATC would not close that rwy when weather becomes IMC at the airport.There is a longest runway startup code in FSX but it has other formula factors that have higher priorities deciding factors that determines runway selection. Just one of these factors is the runway length that is coded to Empty Weight of the planes aircraft.cfg file. The aircraft.air file is used to determine type airplane which 6 different types exist (thanks Tom Gibson for his Cal Classic research).No Engine (Glider)Only called for landing, for takeoff the message 'Call Towplane' is displayed. For landing returns 1000ft.Helo-TurbineMethod not called for landing/take-off. If it was called, it would return 4000ft.Rocket Returns 4000ftPiston Engineif at least one proper engine # block defined -> 2500ft else 4000ft# Block Single Piston Engine Planesreturns 2500ft of runway length# Block Multi Piston Engine Planes Returns 4000ftTurboprop (Cessna Grand Caravan, Dash 8, KA 350)Returns 4000ftJet (B747, B737, etc.) and very complexIf no empty weights specified in the aircraft.cfg: returns 5000ftElse:value = ((empty_weight pounds - 10000) * 2000 / 90000 ) + 5000if ( value > 7000 ) return 7000if ( value < 5000 ) return 5000and this is the most complicated RWY selection based on EW vs runway length The above coding is used for all 4 parallel runways at KLAX or all 5 parallel runways at KATL, etc. to be used simutanously for landing in both FS9 and FSX. The formula allows any Jet plane with a EW of less then 74,000 lbs to use a 6500 ft runway and any plane over 74,000 lbs to be forced to use a runway longer then 6500 ft. That is called runway weight restriction and is used at my FSX EHAM, FSX KATL airports, etc. I also wrote coded weight restriction runways for ImagineSims FS9 KATL. There is a startup runway length formula used but the ARINC 424 XML ILS approach code takes precedence over the longest runway. If no ILS approach code exist a subset group is computed using the longest runway of the group:Score = 0If runway length > 70% of longest runway at airport -> Score += 50Score += tailwind or headwind (tailwind < 0 and headwind > 0)If (unknown 'runway group' flag) Score += 10If (runway landing==yes) -> Score += 100If (runway takeoff==yes) -> Score += 100ILS approach code takes precedence (both VMC and IMC) over the length score for the landing runway which also MUST BE the Takeoff runway (multiple runways that are greater then 7.9 degree true heading)A group is scored by it's base runway. If that runway is the 'primary end' of a runway, (low number) the group will get 100 extra points if 'primaryTakeOff' is true and it will also get 100 extra points if 'primaryLanding' is true.When the base runway is the 'secondary' end, (high number) the group will get 100 extra points if 'secondaryTakeOff' is true and will also get 100 extra points if 'secondary Landing' is true.FS by default sets the primary end as the lowest number for a runway (06/24). If you reverse the 06/24 then 24 becomes the primary end and carrys a higher score by 200 points. Once the score is totaled FS multiplys by 10,000. Note:ALL Runway scoring based on the longest runway is nullified if my Crosswind Runway Technique or Runway Weight Restriction selection is in use. There are default runways in FSX that show the base end as the high runway number such as EGLL RWY 23/05. Since the low number is listed last FSX by default closes rwy 05 so the selection score starts out low and the runway can be closed successfully. When you put it all together the priority list for selection of runway is- Runway group selection <<<==== is 06 the base end or is 24 the base end - IMC/VMC determination <<<<===== Weather Engine - Approach selection <<<<====== ATC engine- Required length calculation <<<<===== Airport/AI Engine is 4th in the list based on type plane or EW if Jet is selected - Runway selection <<<===== RWY 06/07 at KLAX is the desired since Base end is the low number carring the highest score if winds are 0.0 (FS does not know 0.0 and defaults to .001 wind speed) FS does not know what a reciprocal is. The word reciprocal is a 3rd party utility term and FS only knows what the base is per a primary end such as 06 exist. The other end of a runway has no number or does not need a number since the scoring is based on the XML term of base/ Primary vs Secondary. Only the base end of a runway in FS XML coding carry's a actual runway number.A displaced threshold does not always factor in since the landing runway is computed first and the takoff runway must be the same. The invisible target landing point embedded into a runway texture is in the same place regardless of a displaced threshold. However if a runway with the displaced threshold is the active takeoff runway then weight restriction for the length can be factored in.hope this helpsjim

Share this post


Link to post
Share on other sites
Bruce There is a whole lot more to the rules then what a visual shows .........jim
Hi Jim,Thanks for all the info. There is a lot more to r/w selection than I ever imagined :). I fly IFR in real life as a hobby and am aware of runway selection criteria in that environment- and although it additionally takes into consideration noise abatements and other factors to create a "no-wind" preferred r/w, it's amazing how FS uses the info it has to make that selection.Thanks, Bruce.

Share this post


Link to post
Share on other sites