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Guest D-SK666

Flight dynamics: pitch stability & trims

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I really love the tinmouse, superb model, best panel graphics I have ever seen in any addon, but I have questions concerning the flight dynamics. I own the PMDG 737 and I was a big fan of the Dreamfleet 737 in FS 2002. When I compare the hand-fly feeling of the three 737s I use, I wonder why the pitch stability of the tinmouse is so weak (I don`t find the right english word, I mean something like nervouse). I know that the 737, as well as any other airliner, needs a lot of trimming. But the tinmouse is the most difficult plane to trim and bring in a stable flight situation like an approach. With the PMDG or the old Dreamfleet that was never a problem, but with the tinmouse I am constantly fighting against slight up- and down-pichting due to the stability. This is not just a matter of trimming as I have the overall impression to fly a small plane like a cessna because this plane has "power" on her elevators like a fighter-jet.I also own the Dreamfleet 727, Level D 767 and the Hilmerby DC 9 which should allow some comparisons. These two addons are much more stable and absolutely easier to hand-fly. So this should not be a joystick-problem.Of course, I have never flown a real plane except for the good old Cessna 152 in the flight school, so I just carefully ask if this is behavior is really intended by the makers.

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Have you enabled "Fix Control Acceleration" in FSUIPC?See question number 10 in the FAQ in this forum.CheersBob ScottATP IMEL Gulfstream II-III-IV-V L-300Santiago de Chile

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Hi,Besides what Bob points out, what technique are you using? If you have the right power setting for the phase of flight and don't make sudden abrupt changes, I find the Tinmouse extremely stable; I even think sometimes the AP is on when it is not. I will try to address this in the manual on an "Operations" section. I've found a few "tricks" that seem to work OK for flying this jet by hand; and others for that matter.... You know, if anybody uses FSNet it would be awesome to try a dual flight with the Tinmouse... :)regards,Macs :)

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I don`t have a registered FSUPIC, but I know the hint concerning the steering fix. I think this should only help when you switch autopilot off, for example. But actually, fly total manually.Yesterday, I did some further testing with different addons in the same flight situations. To me, it looks this way:1. Averall stabilityIt doesn`t matter if you fly a DC 9, another 737 or the DF 727, all other planes seem to feel a bit heavier. The elevator feels a bit too effective, you can do very fast pitch changes, I think my virtual passengers already have very green faces and the flight attendants complain about this ugly smell...Please, do not take this as something like: "I`ve found a bug" or "... total unrealistic", I just think that the elevator (and the ailerons) should be a bit less effective. Perhaps, the plane needs a bit more moment of inertia (right english word for "Tr

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>I don`t have a registered FSUPIC, but I know the hint>concerning the steering fix. I think this should only help>when you switch autopilot off, for example. But actually, fly>total manually.No, this has nothing at all to do with the A/P. The TinMouse II panel sends a continuous and often rapid stream of commands of various types to FS, and this rapid-fire arrival of commands is what triggers the acceleration glitch. FS does not distinguish between commands sent to the flight controls and those sent anywhere else. Anytime there's a sequence of commands of any type arriving to FS fast enough, it can go into the accelerated command mode, which causes control input changes to be accelerated, making for an unhappy overcontrol situation if not corrected.>To me, it looks this way:>>1. Averall stability>>It doesn`t matter if you fly a DC 9, another 737 or the DF>727, all other planes seem to feel a bit heavier. The elevator>feels a bit too effective, you can do very fast pitch changes,>I think my virtual passengers already have very green faces>and the flight attendants complain about this ugly smell...Not in my system. If you're having the acceleration problem it will indeed overcontrol in that manner. With the FSUIPC control acceleration fix in place it does not offend my sensibilities, which are based on 4000+ hours of r/w experience.>2. Trimming>>I already tuned down the trim button repeat down in the>FS-menue. Nevertheless for me it is more work to keep a>certain pitch attitude with the tinmouse than with any other>airliner. Two or three klicks on the trim button and the plane>raises its nose up in the air and I can do nothing to pull the>nose down again. In this situation the elevator is not>effective enough or the trims are too effective.Lowering trim repeat won't fix control acceleration issues. With the acceleration glitch, every click of trim is being multiplied as if you had the trim key held down, and you won't be able to escape this overcontrol issue.Bottom line, the registered version of FSUIPC already provides fixes for these problems. You've already made your point about not wanting to pay for FSUIPC, but please be aware that I do not have the time or inclination to try duplicating Pete Dowson's fixes within my panel programming. As I've hinted at in the FAQ, I consider FS9 together with the registered full-featured version of FSUIPC to be the basic platform upon which I am building the panel. Anything less than that may result in a less than desireable outcome.RegardsBob ScottATP IMEL Gulfstream II-III-IV-V L-300Santiago de Chile

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Thank you very much for spending your time for that detailed answer. I understand, FSUPIC costs about 25 euros, that is much money for a tool that I cannot use for anything else than a questionable steering improvement for one single plane. And I am a student...My other favorits (DF 727, Level D, PMDG 737, Hilmerby DC-9 and Project Tupolev 154) all would not make any use of a registered FSUPIC.But, and that is actually a "problem": The tinmouse is the plane with the most beautiful panel and and has a superb model of my favorite airliner (the 737 classic). So, please, before I spend the money, allow one last question:This acceleration thing, does this really affect the overall steering in such a subtile way? I mean, I would not call it unflyable, the speed of the trim wheel spinning is o.k., I complain more about the overall agility, especially during pitch changes. Or, to compare two planes: the 727 is a grandpa`s plane compared with the direct fighter-jet-reaction on steering inputs with my 737.If you tell me that FSUPIC would make the overall feeling "heavier", I will buy FSUPIC!

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It's probably best to let some other forum members answer this one. There are a few threads here about the trim oversensitivity, and those I know of who had the issue resolved it with the control acceleration fix. And yes, the acceleration affects the pitch sensitivity. When you press and hold down a key while typing, after a few seconds the key begins to repeat very rapidly. When the trim button is pressed during a stream of other key-based events (generated by the panel) in FS, it behaves as though the button has been held down and repeats the inputs very rapidly. So when you press the trim button, it makes an input many times larger than normal, which means you are constantly overshooting the desired trim setting. That said, FSUIPC is very useful beyond just a control feel issue for this panel...for the end user as well as the panel programmer. It allows major flexibility in axis assignment and calibration, allowing one-to-many mappings of throttle axes, programmable ranges for thrust reverse, graduated-sensitivity axis response shaping, weather effect smoothing, and fixes for all sorts of FS9 bugs like the battery drain bug, the deadly ATC.dll crash when using external ATC programs, control spiking and acceleration, the list is long. Add to that its very flexible button and key programming interface. There's a lot there. And no, there's no commission for me from Pete... ;-)RegardsBob ScottATP IMEL Gulfstream II-III-IV-V L-300Santiago de Chile

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