Yaw Gear with Gear down

[merrja]

Has anyone else with an F model noticed a tendency to yaw with gear down, full flaps and under a decent amount of power such as flying a long ILS? 

[kpaul]

1 hour ago, merrja said:

decent amount of power

This will cause yaw and unless you have a yaw damper installed.

Why fly an ILS full flaps?  If I am on an ILS I would only use partial flaps or no flaps (gasp). I do not enjoy large pitch changes caused by configuration changes while IMC.

[Yetti]

lots of right rudder would be P factor.   On take off power for a turn you don't put in left rudder... you just release right rudder

[201er]

9 hours ago, kpaul said:

This will cause yaw and unless you have a yaw damper installed.

Why fly an ILS full flaps?  If I am on an ILS I would only use partial flaps or no flaps (gasp). I do not enjoy large pitch changes caused by configuration changes while IMC.

Maybe not on an ILS cause most ILS approaches have really long runways on the end of them. But I've seen some LPV approaches to ILS minimums with not so excessively long runways on the end and it's nice to have full flaps by 500 feet to be slow enough when you pop out at minimums.

[Piloto]

Check the nose wheel linkage to the rudder. The nose wheel is uncoupled when retracted and coupled when gear is extended. It may need lubrication or something is jamming when extended. Best way to check is on jacks.

José

[Guest]

Does it do this with partial flaps?  I would check the flap deflection at full flap setting to be sure they are both even.

Clarence

[merrja]

It seems to be with the gear down with >20" of MP.  I'll do some more test flying this week.  Seems to be the same yaw no matter what the flaps setting.  

Edited October 22, 2017 by merrja

[carusoam]

With the long body and tail trim, you get a very noticeable left yaw on descent, and right yaw on ascent....

The exact same, but exact opposite direction, of what @Yetti described above.  Not exactly, because the attitude/yaw isn't as strong going downhill...

Procedure with the long body is to lower the nose, adjust the tail trim to center the ball.

You probably See this with all Mooneys.  You need to be in smooth air to know that is happening.  Having tail trim is just a nice measurable way of putting a measurement on it...

Stuff we learned about in our PP training but couldn't put a finger on it using our trainers at a few thousand feet agl....

i tried to measure a ground speed difference using tail trim to center the ball vs leave the tail centered... Unfortunately both indicated 165 kts GS heading downhill 20”mp, 300 fpm.... the experiment didn't last very long.  The nose was really pushed and pulled around with the trim. Just not showing anything on the gps GS KLN90B.

PP thoughts only. Not a CFI...

Best regards,

-a-

[Hank]

6 hours ago, carusoam said:

With the long body and tail trim, you get a very noticeable left yaw on descent, and right yaw on ascent....

You probably See this with all Mooneys.  You need to be in smooth air to know that is happening.  Having tail trim is just a nice measurable way of putting a measurement on it...

I've never noticed this in my C, descending at whatever my cruise MP was, and 500 fpm. Speed increases nicely to ~170 mph. Now I need to pay attention and see what happens . . . .

[carusoam]

Keep your eye on the ball, Hank!  

Best regards,

-a-

[Andy95W]

On both M20Cs that I've owned, I need right rudder while climbing and just a little bit of left rudder while descending. Both rigged very straight and fast.