PA44 flying crooked

[pchamney 0]

I'm wondering what I've missed. I have a pilot, a front passenger (170 lbs. ea.) and no baggage.

The tanks are both full. The Seminole has started to fly crooked (apparently unbalanced) with the right wing dipping down constantly.

Does anyone have any idea what I should check?

 

Thanks

 

P3DV4

[FDEdev 955]

Joystick calibration

[RichieFly 712]

I noticed this too. I grabbed this aircraft with the sale price; I kept reading how nice it is and all.

It seemed to sort itself out after turning on the YD...I think. Only flew it for an hour last night.

[pchamney 0]

Thanks guys, I'll look into both and report my findings.

[pchamney 0]

Neither of these solved this...

I wonder if Chase Plane has something to do with it.

I'm also using Bert's autopilot mod.

[pchamney 0]

I noticed the aircraft.cfg has opposite values for fuel in the 2nd parameter:

[fuel]
LeftMain  = -7.0,  -3, 0, 55, 2 
RightMain = -7.0,  3, 0, 55, 2    
fuel_type = 1                                
number_of_tank_selectors = 2                    
electric_pump=1

 

I tried setting the LeftMain value to +ve (second parameter 3), but this didn't seem to help.

Maybe someone could post their aircraft config for comparison.

[spearmint_flyer 578]

I've had this problem with the A2A aircraft. Are you sure it's not the P-Factor?

[RichieFly 712]

I just finished another flight. I simulated a check ride: normal takeoff, cruise, slow flight, stalls and full flap landing.

Strangely, I didn't experience the wing drooping this time. I needed to adjust the rudder trim as you might expect. No extraordinary control inputs were needed. I found that the flight characteristics were exactly what I would expect. In fact, very nice indeed.

I didn't use or turn on the AP or YD.

I can't explain why this flight didn't have the roll tendency of the first flight.

[FDEdev 955]

2 hours ago, pchamney said:

I noticed the aircraft.cfg has opposite values for fuel in the 2nd parameter:

[fuel]
LeftMain  = -7.0,  -3, 0, 55, 2 
RightMain = -7.0,  3, 0, 55, 2    

I tried setting the LeftMain value to +ve (second parameter 3), but this didn't seem to help.

As the 2nd parameter is the lateral position of the fuel tank it should be where it is. 

When you start altering values in the cfg file you should really know what you are doing!

Btw, when you moved the left tank to the right side as well there must have been a significant roll moment to the right with full tanks

 

@warriorpilot. The PA-44 has counter-rotating props, no p-factor. Furthermore p-factor makes the plane normally turn to the left.

 

@RichieFly. Strange that you need rudder trim with the counter-rotating props. That's rather unexpected.

[pchamney 0]

51 minutes ago, J35OE said:

As the 2nd parameter is the lateral position of the fuel tank it should be where it is. 

When you start altering values in the cfg file you should really know what you are doing!

Btw, when you moved the left tank to the right side as well there must have been a significant roll moment to the right with full tanks

 

@warriorpilot. The PA-44 has counter-rotating props, no p-factor. Furthermore p-factor makes the plane normally turn to the left.

 

@RichieFly. Strange that you need rudder trim with the counter-rotating props. That's rather unexpected.

You're right that I don't know what I'm doing since the underlying function taking the parameters isn't exposed.  We're left experimenting with values and guessing which parameters affect what.

Perhaps you can inform us about that.

[FDEdev 955]

43 minutes ago, pchamney said:

You're right that I don't know what I'm doing since the underlying function taking the parameters isn't exposed.  We're left experimenting with values and guessing which parameters affect what.

Ever heard of the FSX/P3D SDK?  Every single value concerning e.g. the cfg file is explained there in detail.

No guessing needed.

[pchamney 0]

ok

[Jethro 65]

Just a wild guess, as I don't have this aircraft. If its not P-factor...... does this twin have "Prop-Sync"

[pchamney 0]

5 hours ago, Jethro said:

Just a wild guess, as I don't have this aircraft. If its not P-factor...... does this twin have "Prop-Sync"

Not sure. The props spin in opposite directions in this aircraft, so I would think that various forces would be offset.

That said, I have the controls mapped to single levers as I only have one throttle quadrant.

Anyway, thanks for your reply Jethro.