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Jim: I have examined your curved approach technique and I believe I can duplicate (with some practice) though I don't fully understand the theory behind the technique. For example, is there a hard set rule on the 1-mile turn in the technique? I'm only asking in the event I observe some AI having trouble making the turn. Based on your experience, is it possible to make the turn at 2 or 3nm out and still maintain the curved approach technique? Can the heading vary and if so is there some threshold beyond which your technique no longer works? Sorry for all the questions, but it's nice to have some basis as I think I may need to use your technique in the future.
You can make the turn to final as far away as you want within reason (about 5 NM's.)
Set a Cess172 on runway 07R. Slew up and back toward the mountains that are behind you. Slew 1, 2 or 3 miles or where ever you want the AI to make the turn.
Now slew (rotate) the cessna 172 so it points at 140 degree as a starting point. If that approach path is clear behind you then that will be your target approach path. Turn 150 or 160 to tighten the turn if the turn needs to look more like a base leg to runway 07R.
We are doing 2 things
1. Where do you want the turn to occur from the threshold of the runway (distance from threshold)
2. What approach path do you want the AI to fly before the left turn to final (true heading in the approach header).
Once you have a clear approach path and know where the turn will occur to the runway set the IAF and the FAF T_Waypoints on the approach path of the AI plane (5 NM and 10 NM from center line of the runway on the angle) AND NOT in line with the runway which is a straight in approach.
As per FS9/FSX you are fooling the AI Plane to think the center runway line is the same as the approach path (heading of the AI plane).
The AI Plane is vectored to the approach heading path by ATC because of the 2 T_Waypoints are also on the approach path heading. The AI Plane is approaching the runway from a angle (see my Kai Tak approach toward the checkerboard on 88 degree heading).
When the AI plane gets very close to the extended runway center line the AI Plane say's whoa!!! I have to turn to align with the runway and land.
The closer the turn to final the less the turn can be. AT Kai Tak the turn at the checkboard to runway threshold is about 1/2 mile. The turn can only be about 45 degrees Max based on the poor FDE's AI Plane modler's make. Also the faster the plane on approach has to be considered since the turn will cover more ground distance (Cess 172 turn vs B747 turn).
If the turn to final is 3 miles from theshold the degree of turn can be 80 degrees since the AI Plane has 3 miles to recenter itself on the center line of runway.
A word about AI Plane modlers FDE's
I am only one person (for the last 5 years) trying to show AI plane modler's that in FS9 and FSX there are curves and circle to land approaches built into the default approach code.
Microsoft made their default planes NOT ONLY flyable but AI plane behavior also. A FS9/FSX flyable plane like the B747-400 can turn and align with a runway very well when used as a AI plane. A 3rd party AI Plane has very poor FDE's since it can only land on a straight final approach.
Look at how many AI Planes have trouble shooting my curved Kai Tak approach and then land on the side of the runway. I have been telling modler's that AI Planes MUST be able to turn on short final as per FS9 and FSX. Modler's just don't get it!!!
Modler's and FDE design groups brag about how well their planes look on approach and flair for landing but if you test their planes at PHNL using the default FS9/FSX LDA to rwy 26L which is a curved approach their same AI Plane is junk.
I say that because for 5 years I have ask them to give us AI Planes with proper wingspans/model radius (for parking), use the correct empty weights (for runway selection), use the 13 .cfg values to make a AI Plane behave the same as a default Microsoft plane, stop the sink rate in a turn when gear is coming down (turn to final), and all this continues to fall on deaf ears. Jan Martin is updating all his FDE's to look more like a real plane but I do not know if he is testing the FDE's as per what FS9/FSX requires (see below).
Test your curved approach with a Microdoft default plane of the same size that will use the airport. If the default B737-800 can turn and align then 3rd party AI Planes of same size should be able to do it also. Many can't so I have to push the turn to final back a little bit for the crappy AI planes FDE's.
There is another small problem. All of the FSX Microsoft planes are designed with flying characteristics which uses a updated different type aircraft.air file and companion aircraft.cfg file. ALL 3rd party Freeware AI Planes being uploaded today are designed using FS9 .air and .cfg files. There is no such thing has a 3rd Party Freeware FSX AI Plane and we import these FS9 AI planes into FSX.
PAI did not have the best looking textures and were not Frame rate friendly but they had the best FDE's which the behavior is more toward a FS9 default plane. Arrdvark have the worst FDE's and all the rest fall in between. Most Arrdvarks cannot land/roll out very well unless a ILS approach code exist. Thank goodness for a ILS approach code which can make any AI Plane look good on the approach and landing. Roll out is another story.
If a 3rd party AI Plane is as good as a default FS9/FSX Plane it must
1. Fly a default ILS approach where the approach code controls the atitude of the AI Plane and target point on the runway for touchdown.
2. Fly a non ILS approach such as the RWY 09 at TNCM (visual app)
3. Fly the PHNL LDA 26L approach when airport is IMC
4. Fly the PADU Circle to land approach for either end of rwy 12/30
The default FS9/FSX planes have no trouble with these default approaches. If the 3rd party AI Plane can fly them as well as the default MS planes then I will say that impresses me.
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