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ILS rudder trim. IM STUPID!!!

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ok wellim in a very very VERY dozy mood and im feeling thick so here is my extremely basic commonly asked annoying question.well i enjoy simming and doing IFR flights in bad weather and then rounding it up with a nice ILS landing... however with a crosswind or a windy final approach autopilot drifts and drifts and drifts until off of the rway course now i know that i need to set rudder trim for my landing.do i do this "automatically" and then leave a/p to or do i manually hold the rudder where i need it until touchdown.if a/p lands with the automatic trim how do i set this and how do i know what to set it to depending on wind speed/direction and aircraft weight.Thank you for your much appreciated help.cheersRichy

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Well, Richy, I do not think you are stupid, and I realize some will not appreciate my answer, but let me ask this:1. What kind of airplane are you flying? Sounds like a GA single, since you mentioned rudder trim.2. Have you ever flown an ILS without using the AP? Can you do it?Let me say this:I have a friend who once landed a plane (Cessna 210) in almost zero/zero conditions on an ILS and without using the AP. Real world here, not FS.That being said, I would suggest that you first hone your skills flying the ILS by hand. It's pretty easy once you get used to it. In fact it is not a big deal at all.Seriously, forget about the AP, fly the plane on the ILS by hand, and learn how it reacts. If you are doing this in a jet, dump it, and try first in something like a Cessna 172.Get away, far away, from using the AP, and start learning to control the plane. Learn to "pilot" it.Once you can do that, then you should use the AP.Then, we'll talk about issues concerning the APs use. ;)Hope this helps you. :)Regards,http://www.dreamfleet2000.com/gfx/images/F...R_FORUM_LOU.jpg

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well i can land ils with a/p a can hand fly an approach but have never tried hand flying an ils, sounds interesting i was however flying a jet i was just wondering how i could stop a/p "drifting" off of the rway course. i will give hand flying the ils a go today in a 172.just so i know what is the basic fix for stopping a/p drifting off the rway in a full a/p landing in say a 737 or any commercial jet?Thanks againRichy

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Personaly i would never use rudder trim to correct a x-wind landing approach. My feet or fingers whatever u use would be on the axis for the rudders and compensating this way..Reason being.If you are approaching and reach the DH mark and then call landing, on joy the wind suddenly shifts (which it can) then you are stuck with fumbling about with rudder trim.. Would probably cause alot of comotion in a heavy x-wind with rain low cloud and night time for instance.. Even a terrible crash..Just my 2 cents worth..James.

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ok so in my case to perform a fully automatic ils x-wind landing in 0 visibility i would twist my joystick so my nose faces into the wind.am i correct?Thanks

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Are you expecting the ILS to "autoland" your aircraft? That's what it sounds like. None of the default planes and few add-ons include autoland in their flight model. Even the ones which I own who say they have an autoland feature are not too reliable in really bad weather.That having been said, FS Autopilot-coupled ILS approach is designed for just that; the approach phase of the flight. At some point (for me it's usually 400' - 800' AGL) the autopilot should be disconnected and the landing completed manually. For me, more crosswind means turn it off sooner so I have more time to correct for the imperfactions that you note.R-

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well maintain the rway course and glidslop until 50 feet or so or until the wheels touchdown i know m pmdg flares and will touch down then i disengage a/p.i believe i have seen a full autoland on you tube of the defualt 737.so can i geet a/p to fly in with x-wind oon perfect course for the rway until 50-400 feet?Richy

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Look at the chart for the airport's runway. It will list the DH (decision height) for the Category of ILS approach you're flying.Typically though, it is ~300' AGL...At that point, you either call the landing, disconnect the AP and "hand fly" to the runway, or you call missed approach and execute the missed procedure.

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ok but how do i physically get a/p to approach with crosswind until 300ft/Richy

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The autopilot is limited to what it can do. But this can get you started:While in cruise (or even before you take off, if you don't allow the weather to chnage), figure out which runway is going to be the landing runway. If you look at the Map, you will see some weather information. ATC will try to get you landing into the wind, so you can guess what runway you will get. Conversely, on approach, you can ask ATC for that specific runway.On descent, tune your nav radio to the ILS frequency of the runway you will land on. If you have parallel runways, or if the wind is changing, it's a good idea to have the frequencies of alternate runways available. Make sure that you are recieving the ILS signal. You can use the Ident to hear the morse code, and also watch your main instruments, as you should see ILS bugs.If you are not heading basically at the runway, fly your aircraft so that you are, use autopilot heading commands.Reduce speed, set flaps and lights. Turn on your MKR (marker) radio button to hear the markers on the ground. The glideslope should be active about 10 NM away. You will want to intercept the glideslope from BELOW. That means the ILS glideslope needle should be too high: you always fly your airplane towards the needles. Use engine power to control altitude, not the nose.As you make intercept and the needles come closer to center, press the APR (approach) autopilot button. This should snare the glide slope. If it does not, be prepared to go around and try again. Use the GPS as a moving map to help you visualize your landing. If you have done it all, the APR autopilot should bring you in okay. Recall that the standard glide slope will bring you in at a 3 degree angle, so you should see the ILS needles showing that slope. In heavy weather, you may need to adjust your rudder to point the nose somewhat into the wind. If the weather is really bad, the autopilot might quit on you. In the real world, you could be landing at an alternate airport if the visibility is zero and the wind is that bad, but the professional pilots get paid the big bucks to handle these situations. Personally, I don't trust the FSX autopilot in very bad conditions, but this is what you want, so if the autopilot is handling things and you aren't blown off course, then you can attempt a landing. Around the middle marker, you will want your flaps out and your gear down. Kill the autopilot, be prepared to use a lot of rudder, and try to bring her down in one piece. Always be prepared to go around if you are not 100% sure you will put the wheels safely on the numbers! Practise your ILS landings in good weather before you attempt bad weather! Start off with perfect visibility and no wind. This will help you learn the flow of the landing checklists without being distracted by weather variables. Then, add some weather. Then do it at night. Finally, you can try the full zero-zero approach.As for learning how to use your rudder in the wind, there is a drill you can try. Fly low and slow with the Piper Cub or the Skyhawk over a small city with no tall buildings, but with lots of roads. Turn on some wind, say 20-25 kts at 090. Pick a road and fly along it. Then turn 90 degrees and follow another road. Keep following roads and turn 90 degrees to make a rectangle. Keep the road you are following exactly under the aircraft. You will need rudder to do so. Make several laps. Look at the Map. Your aircraft will have left a trail. Is the trail looking like a box? if so, you have mastered the rudder. If the trail looks like a plate of spaghetti, you need more practise. The next drill is to pick a building or other landmark you can easily recognize. Fly so that the landmark stays right on top of your wingtip as you look directly to the side. Then keep turning so that the landmark stays there! This is a very difficult drill. Once you can do this, you are ready for precise flight. After you try this, look at the Map. Is your flight path an egg-shape around the landmark? If it is, then you are using your rudder to help compensate for the wind as you circle, which is very good. The closer you get to a perfect circle, the more steely-eyed a pilot you will be. Practise makes perfect! An ILS landing requires many separate skills that must be mastered individually before you can put them all together. Jeff ShylukAssistant Managing EditorSenior Staff ReviewerAVSIM

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Thanks for the hep and tipsi will do some drills and start getting closer and closer to the dreaded zero-zeroRichy

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... and you're NOT stupid.Stupid people are the ones that don't ask the question.:-beerchug

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:) thanks for all the help youve given me in perfetcing my far from perfect flight techniqueRichy

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