New Serious Flight Control Problem Showed Up On Last Flight

[cliffy]

Have a short body in the hangar with a serious rudder problem that suddenly showed up on last flight.

Takeoff was normal, climb was normal but on  climb out it was noted there was no left rudder input available.

Only right rudder responded with appropriate movement. The left rudder input was blocked solid, couldn't move the pedal.

Landing gear extended for return and rudder worked normal both directions.

In the hangar the jacks were pulled out and upon retracting the gear again the left rudder input was totally blocked but we found the culprit-

the arm that comes down from the rudder cross shaft that connects with the linkage at the top of the nose wheel well was being locked by part 

of the nose gear tubing when in the retracted position.

The question in mind is - how did this suddenly appear as it never has had a problem before ?

It looks as if the gear retracts too far up in to the wheel well allowing the nose gear tube to go slightly above the bottom of the shaft coming down from above. 

In looking at 2 other short bodies- one shows that the Hiem joint ball end has been slightly ground off for clearance and the other shows a slight touching of the Hiem ball end on the nose gear tube so this may be more prevalent than thought.

It appears as if the nose gear retraction can be lessened (by the use of the eccentric bolts) and allow enough clearance to alleviate this issue and still allow the tire to retract far enough to clear the bottom of the nose gear doors. This will be tried Monday. 

The question still remains on hw this suddenly showed up No markings on the tubing blocking the rudder except for just a little paint missing so this has not been going on for a long time. 

Complete visual inspection by 3 A&Ps has found no discrepancies. No broken or bent parts, loose or missing parts, nothing seems out of line from the gear bell crank under the floor (manual gear airplane) forward through the entire nose gear section. The arm coming down is not bent or broker (still welded to the rudder cross shaft), nothing so far has been found wrong.

Has anyone ever seen this problem before- blocked left rudder?

This is a new for us here. 

 

[N201MKTurbo]

Electric or Johnson bar?

[47U]

1 hour ago, cliffy said:

In the hangar the jacks were pulled out and upon retracting the gear again the left rudder input was totally blocked but we found the culprit-the arm that comes down from the rudder cross shaft that connects with the linkage at the top of the nose wheel well was being locked by part of the nose gear tubing when in the retracted position

Picture?  I’m having spatial disorientation.

[IvanP]

My guess would be that something got bent if this problem suddenly occurred without any prior signs of gradually worsening interference. How was your last landing before this flight - do you recall anything unusual? Any noticeable intereference or change when you retracted the gear after takeoff on this last flight?You mentioned that no bends were detected - did you just eyeball it or did you check the tubes with straight edge? It does not take much of a bend to get some inrteference in Mooney gear. 

[cliffy]

9 hours ago, N201MKTurbo said:

Electric or Johnson bar?

As it says 'Manual Gear"

 

7 hours ago, IvanP said:

My guess would be that something got bent if this problem suddenly occurred without any prior signs of gradually worsening interference. How was your last landing before this flight - do you recall anything unusual? Any noticeable intereference or change when you retracted the gear after takeoff on this last flight?You mentioned that no bends were detected - did you just eyeball it or did you check the tubes with straight edge? It does not take much of a bend to get some inrteference in Mooney gear. 

Nothing out of the ordinary was noted up until the last flight. No hard landings either. Have 2700 hrs in this aircraft. 

Its being looked at again by another set of A&P eyes tomorrow to see if anything can be seen that hasn't been seen yet.  That will be 5 A&Ps looking at it. 

[Echo]

disconcerting. Offset by my new knowledge that once I reach 2700 hours in short body Moonies, I am immune to hard landings. I have that to look forward to sweet.

[takair]

If I’m picturing this correctly, one of those heinous (edit….meant Heim, but spell check corrected to what we are all thinking) joints should have a part of it machined flat for clearance.  However, as you stated, if that alone were the issue, it would have been seen a long time ago.  I would look for slop that finally hit its limit….or….be sure the rudder pedal torque tube has not cracked and partially failed.  I think there are three places to look.  In this case I would look where the small control arm to nose gear link is attached.  I have seen this torque tube crack and break.  Worst case no control, but I can picture a version where it jams.  In the case I was, the gentleman was heavy set and tall and would somehow put his weight into the pedals while situating himself.  Luckily they broke on the ground.  I think this is a similar scenario that sometimes breaks the seat back.  Under certain loads, I can see the force ending up n the joint I mention.  It is very hard to inspect, but can be done….

summary….look at the torque tube where the control link attaches…be sure it’s not cracked….  Repair is a whole other discussion….

 

[N201MKTurbo]

To get a better view of it remove the panel at the bottom of the firewall.

[LANCECASPER]

22 hours ago, cliffy said:

Have a short body in the hangar with a serious rudder problem that suddenly showed up on last flight.

Takeoff was normal, climb was normal but on  climb out it was noted there was no left rudder input available.

Only right rudder responded with appropriate movement. The left rudder input was blocked solid, couldn't move the pedal.

Landing gear extended for return and rudder worked normal both directions.

In the hangar the jacks were pulled out and upon retracting the gear again the left rudder input was totally blocked but we found the culprit-

the arm that comes down from the rudder cross shaft that connects with the linkage at the top of the nose wheel well was being locked by part 

of the nose gear tubing when in the retracted position.

The question in mind is - how did this suddenly appear as it never has had a problem before ?

It looks as if the gear retracts too far up in to the wheel well allowing the nose gear tube to go slightly above the bottom of the shaft coming down from above. 

In looking at 2 other short bodies- one shows that the Hiem joint ball end has been slightly ground off for clearance and the other shows a slight touching of the Hiem ball end on the nose gear tube so this may be more prevalent than thought.

It appears as if the nose gear retraction can be lessened (by the use of the eccentric bolts) and allow enough clearance to alleviate this issue and still allow the tire to retract far enough to clear the bottom of the nose gear doors. This will be tried Monday. 

The question still remains on hw this suddenly showed up No markings on the tubing blocking the rudder except for just a little paint missing so this has not been going on for a long time. 

Complete visual inspection by 3 A&Ps has found no discrepancies. No broken or bent parts, loose or missing parts, nothing seems out of line from the gear bell crank under the floor (manual gear airplane) forward through the entire nose gear section. The arm coming down is not bent or broker (still welded to the rudder cross shaft), nothing so far has been found wrong.

Has anyone ever seen this problem before- blocked left rudder?

This is a new for us here. 

 

I know that there is no rudder trim on an Aerocruze 100, but was there anything during the recent installation that was moved out of the way and put back that could be binding?

[MikeOH]

@cliffy Have you reported this to the NTSB?

 

[201Steve]

this is impossible. Fake news. Johnson bars are impervious to failure of any kind. 
-all Johnson bar owners

[47U]

On 4/20/2025 at 12:45 PM, cliffy said:

In the hangar the jacks were pulled out and upon retracting the gear again the left rudder input was totally blocked but we found the culprit-the arm that comes down from the rudder cross shaft that connects with the linkage at the top of the nose wheel well was being locked by part of the nose gear tubing when in the retracted position.

I can now visualize… and Rob (takair) had a good post…

6 hours ago, takair said:

summary….look at the torque tube where the control link attaches…be sure it’s not cracked….

Cliffy, have you been able to figure out why the interference is occurring?  ‘Something’ must have changed.  Even if the interference resolves when the gear is down, if something is breaking, that could be really bad.

I think the shaved-down Heim bearing is for clearance with the steering horn only.  There’s no change whether the gear is up or down.  I also would think that if the elliptical bushings have not been touched, then something else has changed to cause the interference when the gear comes up.   Something bent or broken.  Maybe something structural, like the nose gear trunnion mount(s) fuselage tubes.

[cliffy]

8 hours ago, takair said:

summary….look at the torque tube where the control link attaches…be sure it’s not cracked….  Repair is a whole other discussion….

 

Been there done that  No issues found Removed bottom plate on firewall for better access and still no problem noted

 

7 hours ago, N201MKTurbo said:

o get a better view of it remove the panel at the bottom of the firewall.

See above  :-)

Nothing on the autopilot install that would have affected it    Roll is ailerons and pitch of course is elevators

 

@MikeOH  Not yet but I will     Don't know if that ever happened 25 years ago when I had a 737  lock up in roll twice! Company had me do a test flight with maintenance on board- scared him when it happened again on the test fight.  Typical "can not duplicate squawk" until the test flight.

Turned out to be a bad roll control module mounted on the keel beam in the wheel well. 

47U   Your pictures are correct    It has now been looked at by 6 A&Ps  None can see any reason WHY it happened but can see WHAT is going on.

NOTHING is broken, bent,  loose, missing.  Even used pry bars to see if we could find any loose play - NOTHING. 

We adjusted the eccentrics to lower the nose gear in the wheel well (slight movement down) so that it now clears the arm. Spent the day in another shop with them looking at it and doing the adjustments. The nose gear doors also needed to be adjusted after lowering the gear in the well of course. Gear works just fine now along with the rudder input. Only thing left is reassembly and test flight. 

 

47U  WHO has a nose wheel well that clean?  :-) 

 

[Flyler]

You've looked under, have you looked above? If the pivot point "2" were to lower somehow, either by wear or loose bolt, perhaps the link would drop low enough to contact and interfere.

[N201MKTurbo]

Well, according to the parts diagram, you have link 22 in backwards.

[Ragsf15e]

15 minutes ago, N201MKTurbo said:

Well, according to the parts diagram, you have link 22 in backwards.

Good catch!  

[47U]

3 hours ago, cliffy said:

47U  WHO has a nose wheel well that clean?  :-) 

Last summer I went through the whole nose gear.  Stripped, painted, bushings, donuts, steering link and upper structure from LASAR, the whole she-bang.  And I’ve been able to get my oil consumption (leaks/blow by) down to a quart every 12-15 hrs which helps.  It was a mess before I started, though.  Something had to be done.

55 minutes ago, N201MKTurbo said:

Well, according to the parts diagram, you have link 22 in backwards.

Don’t disagree with your statement.  However, I put it together the same way as I took it apart.  The shaved Heim bearing obviously goes into the steering link for clearance issues.  Could be the IPC is wrong, or over the 35 years before I owned the airplane someone deviated.  I would guess that it had been apart before I took ownership.  At this point who knows?  Is it worth fixing to match the IPC?  Debatable.      

Below is the IPC for my serial number.  Lacks clarity… ambiguous, at best.

 

 

Edited April 22 by 47U
IPC graphic added.

[takair]

I could have sworn I remember the shaved part as going aft and down to better clear the gear, but I can find no evidence of that at the moment. 

[47U]

3 hours ago, takair said:

I could have sworn I remember the shaved part as going aft and down to better clear the gear, but I can find no evidence of that at the moment. 

That makes a lot of sense.  Because you are right.

And I’m wrong, again.  I took the picture to be sure, and then I didn’t follow it.  A short search into the archives (in the light of morning) revealed…

I’m lucky I didn’t have the same interference as Cliffy.  Lucky.  I just returned from Willmar for tank reseal.  It was over 30 hrs tach time, there and back.  But, I’ll be fixing this before further flight.

Rob, not sure if I’ll ever get to the Northeast, but I owe you dinner, or at least a beverage!

[takair]

It’s a good forum, we all learn.  The manual is not very useful on some of these topics.  Rich also caught that the link was backwards.  Cliff’s issue is still a little disturbing, especially in light of the recent 310 accident in Boca.  

[Echo]

You guys never cease to amaze me on your knowledge of these airframes.  What a great thread.

[cliffy]

57 minutes ago, Echo said:

You guys never cease to amaze me on your knowledge of these airframes.  What a great thread.

EVERYONE learns here EVERYONE!

In fact I hadn't thought to look and see if way back when someone before me (27 years ago) might have reversed the link. 

I'll be looking at it today  before I relube everything under the floor and replace the belly panels to see if there is a flat spot on the other end.

Now my link does NOT have any threads showing on the male side Interesting difference I've seen on 2 other Mooneys.

The original maintenance manual (the only one we ae REQUIRED to go by) is very sparse. Back then A&Ps were on their own a lot -

before attorneys. 

[takair]

4 minutes ago, cliffy said:

EVERYONE learns here EVERYONE!

In fact I hadn't thought to look and see if way back when someone before me (27 years ago) might have reversed the link. 

I'll be looking at it today  before I relube everything under the floor and replace the belly panels to see if there is a flat spot on the other end.

Now my link does NOT have any threads showing on the male side Interesting difference I've seen on 2 other Mooneys.

The original maintenance manual (the only one we ae REQUIRED to go by) is very sparse. Back then A&Ps were on their own a lot -

before attorneys. 

And before digital cameras…lol. 

[Ragsf15e]

I actually just bought both sides (male/female) ends of that link, the center nut, and the bolts/nuts that secure it.  All of it was available from lasar and/or Mooney.  My nosegear is ok right now, but getting loose in that joint, so my mechanic wanted the parts on hand next time we have it on jacks.  I’ll carefully consult the manual now to make sure it’s in right!

[EricJ]

It's possible that the orientation of that link makes no difference.