Trimming Mooney Bravo under instruments

[Guest davis078]

Trimming this plane under IMC is driving me crazy. The HSI is not precise enough to zero in on a level attitude, and the plane tends to oscillate from climbing to descent too much. And, of course, the VSI is great at telling me what I was doing 5 seconds ago but not so good at helping me get level.Is the Bravo this hard to trim in real life? Does anyone have any tips on how to efficiently trim this aircraft and to quickly damp out these oscillations with no outside visibility? It's hard to mess with charts and radios when I'm having to fight the attitude this much. . . maybe I just need to practice more.Mark

[Guest JIMJAM]

You can CHEAT by changing stabilty related lines in the planes cfg file.But YES, there are plaes in REAL life that cannot be perfectly, hand off trimmed.There are factors such as weight and balance,fuel burn, winds and how the plane is rigged. Some have tanks on the left and right you switch back and forth so its a lateral cg issure. Others as the plane becomes lighter, wants to climb.Thats one of the reasons they invented the autopliot.Try flying a real helicopter for 100 miles. I have flown real mooneys but as with most light planes, sometimes you get a smooth as glass ride,others the sky is full of potholes.Some are rigged really well and some no matter what wants to crab,climb or stay put.As I said, you can cheat with the .cfg file to make it rock solid and more resistant to being upset but I own the Carendo Mooney at I would not touch a thing.Also widen the deadzone and lower the sens of your joystick. Might help.

[Guest RonB49]

Hi Mark,>the VSI is great at telling me what I was doing 5 seconds ago but >not so good at helping me get level.I'm not a RW pilot but I believe this is correct. The VSI does lag behind the movement of the plane and is not recommended as an aid to pitch trimming the plane. So watch the attitude indicator.Also consider that in the real plane you are turning a trim wheel and the airfoil movement is smooth and directly proportional to amount that you move the wheel. In the sim, pitch trim is step-by-step digital signal that is not so precise. Most devices that we use for pitch trim (a rocker switch on a yoke, for instance) are mapped to the keyboard's NUMPAD 1 and NUMPAD 7 keys. I've always thought there might be a market for a real trim wheel device for flight sim but I don't think one exists.So I use the trim keys or yoke rocker to get me as close as possible to level, then use the throttle to maintain the correct altitude. With the throttle I have an analog device that gives me the fine tuning ability required. Having said all that, nowadays I generally use the autopilot; it's so much easier.R-

[Guest JIMJAM]

The ones I flew had auto trim and for people coming from manual wheel trims,often over trimmed.The mooney has alot of positive dih so its real stable. Its also clean and picks up speed fast pointed down.PS-Do not spin a real Mooney.There is a elevator_trim_effectiveness line in the aircraft.cfg. Raise it/lower it and see what happens.You can always put it back to 1.IMO alot of the defaults and some paywares trims and elevator effectivness are always touchy.If you like the default, get the Carendo.There is also a real Mooney owner here who might see it and jump in.

[Manny 1,293]

Every aircraft has a Gait. You should know, for the specific aircraft you are flying, for a given power setting, at a specific attitude setting what the IAS should be. IF you know these three parameters at various operating conditions. Climb, cruise, descend (Precision), descend (non precision), then you simply fly by those numbers. Thats how one flies in IFR. Not trial and errorHere is one for Mooney. Try this. Do not chase the VSI. If the aircraft oscillates, don't sweat it, it would come find its equilibrium. Just maintain proper power setting and attitude. and then wait for it to steady, then trim it.http://forums.avsim.net/user_files/188060.jpg

[Guest byoungblood]

>Hi Mark,>>>the VSI is great at telling me what I was doing 5 seconds ago>but >>not so good at helping me get level.>>I'm not a RW pilot but I believe this is correct. The VSI>does lag behind the movement of the plane and is not>recommended as an aid to pitch trimming the plane. So watch>the attitude indicator.Actually, you should watch the altimeter to determine level flight, then use the pitch trim to adjust your speed. Trying to do it the other way around is what results in the oscillations, as you end up chasing the VSI and altimeter trying to maintain your altitude with pitch the aircraft with pitch. Then you can look at the attitude indicator to see where the nose is for that power setting and airspeed. Granted, small manual (not trim) corrections may have to be made to keep the aircraft at your desired altitude, but as long as you keep the power set the same and maintain your airspeed, the aircraft should hold altitude with a minimum of control input.

[Guest davis078]

Thanks. This advice is just what I needed. With some patience I've been concentrating on keeping the pitch right with a given power setting, and the oscillations have been damping down by themselves. I'm getting much better at this now.About coming up with these "numbers". . . is that something that you come up with yourself through experimentation, or are the preferred configurations published in a POH or something?Mark

[Manny 1,293]

Hi Mark.You most likely won't find these in a POH. But its generally known for most aircrafts. But its not very hard to take the aircraft up to get these yourself.Manny