Abrupt out of roll trim condition

[FlyingScot]

Greetings all, and Happy Holidays to everyone.

I was wondering if anyone has had an experience similar to this:

I have been flying and enjoying my Ovation2, indeed have taken it up several times over the last week (a surprise this time of year in the Midwest) and yesterday I went for a last test flight in the sequence to further exercise a new 750/650 install.

This time out when I raised the gear after takeoff, the plane wanted to roll left. Not overwhelming, but it took constant and not insignificant right pressure to level it out. Ball was centered, and it did not correlate with yaw. No warnings on the gear, and no obvious turbulence or loss of airspeed. But a very noticeable out-of-trim condition. The autopilot could handle it, but disengage it and the plane rolled left immediately. And when I say rolled, the bank angle continued to increase until corrected/stopped.

The plane has always flown beautifully true, so this was a surprise - so I hightailed it back to the field, and when I put the gear down, the roll pressure went away. Three greens, and a landing w/o incident. And yes the emergency gear extension handle was locked .

Obviously, all of this points to the gear - maybe not closing completely on one side? A door hanging into the airstream? After landing, I did notice the inner door linkage on the right had a lot more slop than the left when I pulled on the door - but it was closed nonetheless.

My A&P is going to put it up on stands before I take it out again, but I was wondering if anyone has had something similar happens to them - 

Thank you in advance - and all the best for the Holiday Season - Bob

 

[N201MKTurbo]

I'm sure your mechanic will fix the gear doors.

[PT20J]

I would expect mis-rigged gear doors to cause a yaw rather than a roll and even at that nothing of the magnitude you describe. The aileron control tubes run close to the gear bellcrank. Should be easy to figure it out if you put it on jacks and remove the belly and observe the gear motion.

[EricJ]

Did you take off behind anything large?   i.e., potentially wake turbulence?

 

[Mooneymuscle56m]

23 hours ago, FlyingScot said:

Greetings all, and Happy Holidays to everyone.

I was wondering if anyone has had an experience similar to this:

I have been flying and enjoying my Ovation2, indeed have taken it up several times over the last week (a surprise this time of year in the Midwest) and yesterday I went for a last test flight in the sequence to further exercise a new 750/650 install.

This time out when I raised the gear after takeoff, the plane wanted to roll left. Not overwhelming, but it took constant and not insignificant right pressure to level it out. Ball was centered, and it did not correlate with yaw. No warnings on the gear, and no obvious turbulence or loss of airspeed. But a very noticeable out-of-trim condition. The autopilot could handle it, but disengage it and the plane rolled left immediately. And when I say rolled, the bank angle continued to increase until corrected/stopped.

The plane has always flown beautifully true, so this was a surprise - so I hightailed it back to the field, and when I put the gear down, the roll pressure went away. Three greens, and a landing w/o incident. And yes the emergency gear extension handle was locked .

Obviously, all of this points to the gear - maybe not closing completely on one side? A door hanging into the airstream? After landing, I did notice the inner door linkage on the right had a lot more slop than the left when I pulled on the door - but it was closed nonetheless.

My A&P is going to put it up on stands before I take it out again, but I was wondering if anyone has had something similar happens to them - 

Thank you in advance - and all the best for the Holiday Season - Bob

 

Definitely check the gear doors like others mentioned.  I noticed a vibration that would come and go, never caused noticeable yaw. Mine wasn’t fitted well and fluttered until the front hinge broke and peeled back and made a mess that cost $3K.  

Edited December 10, 2019 by Mooneymuscle56m

[carusoam]

Any other maintenance to go with that?
like Gear rigging during annual at all?
 

Take a look at what was done in the tail area as far as antenna wires or anything that could possibly be touching something that shouldn’t  get touched...

Did anything get installed on the back shelf? Remote G devices like audio panel or transponder?

See if the batteries are sitting in the right places...

Some odd things I have heard about on MS...

PP thinking out loud...

Best regards,

-a-

[M20S Driver]

Here is one more.  I had the exact same issue when my flap was at  10 deg doing 130 kits indicated.  My mechanic replaced a couple of micro switches to fix the flap actuation problem. 

[Stephen]

Had an unintended  *single* speed brake deploy once... more of a big yaw, but that would be visually obvious. 

[bradp]

Check your flap rigging 

a left roll will happen when someone walks on your flap during cabin entry 

[ReconMax]

Check your flaps and make sure they are retracting fully. Left roll might mean right flap is catching. Potentially, if you wait and retract your flaps after a certain speed is attained, the upward pressure on the flap can cause it to "catch". It'll work properly on the ground and maybe even if you retract quickly on takeoff. The catching I am talking about wont happen if everything is rigged correctly and such. It happened to me because there was a wrong size rivet with a big fat head that was catching on the wing. Potentially, other things might cause similar issues.

You have to look really close while in flight at the flaps when you are experiencing the roll tendency. Compare both sides and take pictures to show your mechanic. Mine was only about a half inch extended when it caught which caused a significant but controllable roll tendency...

Just an idea...

[steingar]

Reminds me of the day my autopilot turned into a killbot.

I was taking off from a local airport after landing and chatting with a pal.  We were both going to fly to a local airport to get lunch.  I took off, and while I was retracting the gear felt a strong leftward roll.  Went ahead and finished stowing the gear, and when I looked up I was looking at a row of hangars approaching me rapidly.  The airplane had rolled into a steep bank, the nose dropped, and I had about 2 seconds to live.

I got the nose up, but the airplane was still strongly rolling to the left.  i figured either I had an autopilot problem or something was jamming the ailerons and I was likely dead.  But I hit the remote shutoff for the autopilot and the aircraft leveled out.  I flew out of it and went on my merry.  My friend who was watching thought I was going to die.

Never did figure out why the autopilot did that, and I've since  just owned it up to crazy autopilot stories.  Seems everyone has one.  I do have a new item on my pre takeoff checklist.  "Autopilot off"."

[PT20J]

Flew a C-310 for a while that had the old Cessna autopilot with the controller mounted to the aft side of the throttle quadrant. I had just finished leaning at cruise altitude when the airplane suddenly wanted to roll left. First thought of course was an engine problem, but this was clearly a roll, not a yaw. Took a couple of minutes to figure out that I had brushed the autopilot ON rocker switch (they were very "soft" switches) and the autopilot came up in roll mode with the turn knob turned to the left. Autopilots are your best friend -- until they're not.

Skip

 

[EricJ]

1 hour ago, PT20J said:

Flew a C-310 for a while that had the old Cessna autopilot with the controller mounted to the aft side of the throttle quadrant. I had just finished leaning at cruise altitude when the airplane suddenly wanted to roll left. First thought of course was an engine problem, but this was clearly a roll, not a yaw. Took a couple of minutes to figure out that I had brushed the autopilot ON rocker switch (they were very "soft" switches) and the autopilot came up in roll mode with the turn knob turned to the left. Autopilots are your best friend -- until they're not.

Skip

The Century III in my J is mounted in the console under the throttle quadrants, and it's really easy to bump it "ON" when adjusting the cowl flaps.    Mine is fubared with an unknown fault that makes it roll hard one way or other after being on for about ten seconds, so before I pulled the breaker permanently I had a few of those exciting wth-is-it-doing moments.