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Rudder effectivity tables

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Recently , in the general forum, somebody commented on the lack of rudder control in some aircraft models - and I have noticed this myself.Could somebody comment on the tables shown below -- they are from the air files of 3 different aircraft . What do they mean and are they able to be altered.Thanks Barry

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Unless you have an aircraft that is very uniquely different from the ones we know and love, the tables should not have to be altered assuming that the air file is of the correct type for the airframe.Generally, If you have distances from CoG set correctly, square footages, and efficiency factors in the ballpark, you should have a reasonably responding rudder.Look at these records in the .air file: 1206 for general stuff and 1101 for the adjustments to influence response authority and yaw, and Side Force - Rudder. And, remember some forget the yaw damper is left on (rec 1102). :-)Then, assure that flight tuning in the aircraft.cfg isn't "dumbing down" the settings.Milton

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>Unless you have an aircraft that is very uniquely different >from the ones we know and love, the tables should not have >to be altered assuming that the air file is of the correct >type for the airframe. Trouble is that many of the addon aircraft do not fit into the standard categories and are indeed uniquely different.As far as I can see, these standard categories are such things as twin engined jets, single engine props, single engine turbos, etc - presumably of modern design as per the default aircraft.Many of my aircraft are single and twin engine prop taildraggers of historic design ( you could hardly compare their rudder designs to modern day Cessnas and Beech Barons) and twin and multiple engined historic prop driven airliners.So, with the diagrams I attached, just what do they mean? And which one is applicable to which type of aircraft?Barry

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Barry,I am certainly no aeronautical engineer. If you want tables calculated specifically for your aircraft design, engines, wings, weights, dimensions, curves, and shapes (don't we all), then I recommend you hustle on over to Mudpond, download the infamous spreadsheet, and associated utilities, and have it calculate accurate response tables, air and cfg file parameters based on real world data. The results put your aircraft within 1% of the actual performance numbers.It works and I am impressed with the results. Everything else is guesswork, trial and error without the degree. :-)You can get it here:http://www.mudpond.us/Milton

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If you look at the Control Surface displacements applied in Record 311 of the Airfile in Radians, and as Degreees in the Cfg file, you will find that the actual displacement as shown in AFSD or Jerry Beckwith's Gauges frequently is - for the Rudder and Elevator - only about 60 percent of these figures. The Aileron does not seem to be affected. Effectivity is a much larger can of worms involving Record 1101,Scalars and Airspeed. The actual physical deflection is affected by the Records you posted. Jerry's Spreadsheet applies this reduction in deflection although the book figures are correctly entered in the Data Fields.That this is intentional is confirmed by the Elevator Pre-Takeoff Check deflection he recommends. His excellent Spreadsheet is primarily for CFS1, CFS2 and latterly CFS3 Warbird requirements, which are different from Fs2002 drivers.. Effectivity is easily changed using Scalars, although I dislike using them, feeling they are an admission of my failure to properly massage the Air file entries. perhaps someone more knowledgeable will provide an answer.BestAlex

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