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Christopher Low

Trim settings

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The trim settings in FU3 seem to be initialised for take off. That's why I never have to touch them ! However, those in FS2002 are very different. Every aircraft that I have tried seems to have the trim set to "Journey to the centre of the Earth" mode :-) In other words, even with maximum flaps and maximum power, the plane still wants to dive unless a certain amount of pressure is applied to the joystick.Since I have absolutely no idea where the trim should be set for take-off for ANY aircraft, would anyone here like to explain this. Since the trim controls themselves don't seem to have any indication of the angle of elevator deflection, this causes problems when a particular setting needs to be described. I am currently using the FFG Saab 340, and I would very much like to know where the trim should be set for take-off, since I don't want to EVER touch this again :-lolChris Low,ENGLAND.

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Oh Chris... it's far beyond me how you can demand so much from your flight models that you can't even find a plane you like to fly... and then want to "dismiss" something that is so fundamental and important to flying ANY aircraft.One day you will take that real world GA sample flight and things might change for you :-lol

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The trim looks like a wheel that you can scroll up or down in a slot and there's a white indicator showing the setting. Find the trim read-out (main panel or pedestal window) and set the trim tab somewhere in the middle. Most FS2002 aircraft start out being trimmed way down (trim tab high). There may even be a position marked as "TO" for take-off in the middle range.If you haven't assigned trim to two of your joystick buttons it would be a good idea to do so. Keyboard commands: Numpad with num lock OFF -- key 1 = trim up, key 7 = trim down. With trim assigned to two of the joystick buttons, preferably choosing buttons on top of the stick, proper trimming will be easy. In fact, many real aircraft have trim buttons on the yoke. I'm currently using a stick with two buttons placed on top of the stick, a bit to the left, one above the other. Trim down is assigned to the upper one and trim up to the lower one. I use my thumb to fine-tune trim during all phases of flight. And, I use the exact same button assignment for both sims.best regards,Hans Petter

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I've forgotten how "left drift" for single engine airplanes was simulated in FUII/III. There is a constant complaint about it in FS2002.......... as if something is terribly wrong! :) This is in addition to the "stuck to the runway"--- complaints!!L.Adamson

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>Larry, >>Please explain. >Chris,I don't remember if FUIII required some "right" rudder during the takeoff roll and climbout----------------- in aircraft such as a single engine Cherokee. Some simulations don't seem to require any on the takeoff roll. Fact is, if I was to steer onto a runway with a real Cessna 172 or Piper Archer, I'd have to be immediately adding some right rudder as I pushed in throttle. Otherwise, the plane will tend to bee-line for the left side of the runway. This effect will remain after takeoff until I'm leveled off in cruising speed. At that point, most small aircraft are pre-trimmed with manually set trim tabs on the rudder, or perhaps off-set vertical stabs. The engine is even off-set to the right on the engine mounts.Or..........you can also have adjustable rudder trims. This pull to the left is caused by "slip-stream" effect of air moving off the propeller in a spiral pattern, engine torque, and P-factor. If the engine rotates the "other" direction, then the effect is reversed. Counter-rotating props will cancel it out. Engines mounted to push instead of pull will have other effects, etc.I once was barreling down the runway in a real Cessna 172 (they're not really that fast!) when the engine sputtered to near idle just as I was going to rotate. With no more torque, the plane made an immediate drift to the right of the runway because I was applying a fair amount of right rudder. It's surprising just how much rudder is required to keep them straight. I like to see simulations where my rudder pressure in single engine GA aircraft is constant, and the plane doesn't seem to start drifting in both directions. In reality, the "feel" is almost like riding the edge of a sloped gutter, or riding the edge of a wake on a slalom water ski. You're constantly pushing against it, even after liftoff from the runway. Even the FS2002 defaults do this quite well, and some third parties even better. But it does get many complaints from those who don't know of the effects. Same with not setting trim settings before takeoff. It makes the plane seem stuck to the runway, and then more pull to rotate which results in a high angle of attack and possible stall.In real life, if you've done a touch and go, and had some "down" trim in for the landing, you'll really feel it while trying to pull back on the yoke for takeoff. You'll immediately be grabbing the trim wheel to trim the force out. With a home PC, this additional force is never really evident, therfore you just keep pulling back until the plane leaps off the runway. My own mind is conditioned for immediate relaxing of the yoke/stick after breaking ground, depending on the airplane, but it's much better to trim for takeoff beforehand.L.Adamson

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Larry,Indeed, FU3 aircraft have this capability. It varies to some extent with different aircraft - the DC3 has a mighty kick, so does the Mustang and the GeeBee. Other aircraft do it to some degree, I'm not sure which ones though.Just make sure 'engine torque' is turned on ;) This can be hard if you don't have rudder pedals though.Jon Point*************************(effyouthree@hotmail.com)*************************

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Larry,The annoying factor about the trim settings is that I have absolutely no idea where they should be set for take-off. Of course, this is all irrelevant now, since FS2002 has been removed from my hard disk....................but then you already knew that :-)With respect to the "left drift", I was aware of this.Chris Low,ENGLAND.

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Hello Larry,in the FU3 physicsfile, which is defined for each flyable model and part of the planes resource file *.RES we sure can add this prop-effects.For each lifting airfoil can be defined a constant named: //propEffectOffsetx.xxwhere we can define this prop based side-drag for each of the defined airfoils (in FU3 this are the simulated wing surfaces which simulates reality close the lift up angle-of-attack behavior etc., for the main wings, rudders, elevators and so on).At the DC3 for example I only defined a little prop effect at the rudder foil. This is sure very little and may be we should increase this effect. But if we do so it is sure critical to hold such an big taildragger in the middle of the runway. I didn

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The stock piston aircraft of FS2002 don't have off-set engines. However, we may edit the aircraft.cfg to reduce torque by moving the engine axis a bit off-center. I've modified most of the piston aircraft to effect this. Quoting Tom Goodrick: To fix the torque problem, I did what aircraft manufacturers do. I offset the engine position to the left. I set it 0.5 feet or 6 inches left (negative y). Those of you who edit FU3 aircraft may consider the same procedure -- just move the engine(s) a bit left of "neutral" and test what this does to counter excessive torque. But remember, the idea is to get it right -- not to cancel out torque entirely. The new GeeBee might be a candidate for off-set engine.Hans Petter

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>The stock piston aircraft of FS2002 don't have off-set >engines. However, we may edit the aircraft.cfg to reduce >torque by moving the engine axis a bit off-center. I've >modified most of the piston aircraft to effect this. Quoting >Tom Goodrick: To fix the torque problem, I did what aircraft >manufacturers do. I offset the engine position to the left. >I set it 0.5 feet or 6 inches left (negative y). >When you say left, how are we looking at it? If I was to stand on my seat and look down at my Lycoming (prop turns C/W-- looking from the front), the rear of the engine is offset to the left side of the firewall, but the prop is pointing slightly to the right. It's the rear of the engine that is offset, so that the prop ends up on the centerline.Regarding FS2002, the default piston aircraft were not bad when using rudder pedals. FS2K was very "squirrly" at throttle up and this was tamed in the next version. The left drift feels natural to me. When Rob Young re-did some files for the 182's it was even better, as well as some other files since then. L.Adamson

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>The trim settings in FU3 seem to be initialised for take >off. That's why I never have to touch them ! Chris, Somehow I missed the true meaning of this the first time around. From this post and others, I'm getting the impression that you don't use trim after takeoff. Only power settings to climb and descend.In real life, you'll be making constant trim changes with different power settings, as well as some in cruise to counteract small amounts of climbing or descending. For instance, If I was to pull power back for a long descent, then I'd also have to add some down trim to keep the airspeed that I want. Note: this DOES vary with different aircraft. For flight simulation. I use two buttons on my joystick, and use them alot. My "mind" fakes trim very well because I know what a real plane feels like. One thing for sure, you'll never set trim just once and then forget it!!!!!L.Adamson

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FS does not support "prop pointing slightly to right". Our only option is to "move" the entire (flight dynamics) power plant to the left, "left" meaning the left side of the fuselage. I know, in real life the prop axis is set at an angle to counter torque but the best we can do in flightsim is to move the propeller in the right (eh, left :-)) direction, even though it keeps pulling straight ahead. You simply pretend that the entire power plant is shifted a few inches to the left.Hans Petter

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