Solved: Are my main gear hitting the wing on retract?

[Aerospace]

 

Solved: low throttle switch malfunction.

1992 J: The other day I had an alarm when I tried to retract the gear. After several seconds, I put the switch back to the down position (alarm went quiet) and the gear would noticably (I tried it twice) make the usual clunk of going back down and the barber pole would go back to showing green gear down.

I informed the tower that I had experienced this anomaly and was returning to land with gear indicating safe down and locked. They confirmed they could see the gear was down and provided some calming comments like: 'better down than up' and 'that woulda made for a long trip'.

After a safe landing, I inspected the gear and saw what looks like evidence of rubbing. Paint on the tire shoulder, scuffs and scratches on the wing behind the wheel well.

Here are some facts and pics:

1. My first plane, bought last year (lots to learn)

2. Have not checked date on pucks

3. No log entry for replacing pucks ever

4. First time having any gear issue

5. Was a 95 degree day

6. Did not try pressing override button

7. I already plan on replacing the pucks

Do you think old squished pucks can cause this or is this something else?

[Aerospace]

Also, who is near CRG in Jacksonville FL and wouldn't mind lending me some jacks for a swing test. 

[N201MKTurbo]

The only thing I can think of is the wheel was over extended. This can only happen if the bolt at the top of the pucks came out or the shaft that goes through the pucks is broke.

Hard to imagine any of that happened, but i would get it on jacks and check it out.

I can't think of any way the pucks could do that.

[EricJ]

Definitely need to do a gear swing.    Something is very out of whack to do that, so it should be evident during a swing.

 

[N201MKTurbo]

I think the wear mark in the wing came from the gear doors. Do you have the lower gear doors?

 

[mike_elliott]

Those are not the "monster" retreads that have been known to catch in the well are they? Smart move to have a swing test done. Jake at Daytona can do this in short order for you

[N201MKTurbo]

The first place Monster retreads hit are on the center zerk. These are not Monster retreads. Let's just say I have experience with this.

BTW,

Since I ground down the monster retreads so they fit, they don't seem to wear at all. They have been on the plane for about 5 years and still look brand new....

[Ragsf15e]

26 minutes ago, Aerospace said:

1992 J: The other day I had an alarm when I tried to retract the gear. After several seconds, I put the switch back to the down position (alarm went quiet) and the gear would noticably (I tried it twice) make the usual clunk of going back down and the barber pole would go back to showing green gear down.

I informed the tower that I had experienced this anomaly and was returning to land with gear indicating safe down and locked. They confirmed they could see the gear was down and provided some calming comments like: 'better down than up' and 'that woulda made for a long trip'.

After a safe landing, I inspected the gear and saw what looks like evidence of rubbing. Paint on the tire shoulder, scuffs and scratches on the wing behind the wheel well.

Here are some facts and pics:

1. My first plane, bought last year (lots to learn)

2. Have not checked date on pucks

3. No log entry for replacing pucks ever

4. First time having any gear issue

5. Was a 95 degree day

6. Did not try pressing override button

7. I already plan on replacing the pucks

Do you think old squished pucks can cause this or is this something else?

Obviously you need a swing check on the ground, and @EricJand @N201MKTurbo are way smarter than me on this, but i think you’d blow the gear actuator cb if the gear hit something short of retraction… I’m guessing you have a different problem… but then I trust the other guys too, so…

[PT20J]

Worn shock disks will not cause a mechanical retraction issue (They cause issues on airplanes with squat switches, but yours should have an airspeed safety switch). You can check the disks by putting in full fuel and measuring the gap between the top retaining plate above the disks and the collar on top of the center post that goes through the disks. Max gap is 0.6 in. (Ref Service Manual 32-81-00).

The marks under your wing look to me to be where the MLG fairings should be. Has your plane been modified with the flush gear doors STC?

Since the gear went up, it is probably not an issue with the airspeed safety switch.

It sounds more like an issue with the up limit switch.

The gear actuator is rated for 2000 lb so if the gear were hitting something I would think something would be noticeably bent.

 

[Ragsf15e]

My terribly uneducated guess… throttle gear warning switch.  Free on the internet.

[N201MKTurbo]

2 minutes ago, PT20J said:

Worn shock disks will not cause a mechanical retraction issue (They cause issues on airplanes with squat switches, but yours should have an airspeed safety switch). You can check the disks by putting in full fuel and measuring the gap between the top retaining plate above the disks and the collar on top of the center post that goes through the disks. Max gap is 0.6 in. (Ref Service Manual 32-81-00).

The marks under your wing look to me to be where the MLG fairings should be. Has your plane been modified with the flush gear doors STC?

Since the gear went up, it is probably not an issue with the airspeed safety switch.

It sounds more like an issue with the up limit switch.

The gear actuator is rated for 2000 lb so if the gear were hitting something I would think something would be noticeably bent.

 

When I bought my plane the gear was all messed up. I can tell you that it will blow the breaker before it does any damage.

 

[Shadrach]

Good advice above. I will add that I do not see anything that looks odd in the attached images. The gear doors leave witness marks on all Mooneys over time. I put prop tape on the doors in the area where they contact the wing. I see no scuffing or paint tire transfer in the wheel wells, just the typical collection of crud the all accumulate if not washed regularly.

Edited August 2, 2023 by Shadrach

[Aerospace]

36 minutes ago, N201MKTurbo said:

I think the wear mark in the wing came from the gear doors. Do you have the lower gear doors?

 

No, but it may have had them before I owned it.

32 minutes ago, PT20J said:

Has your plane been modified with the flush gear doors STC?

I don't think so. It did have some kind of speed kit STC installed though.

[PT20J]

13 minutes ago, Aerospace said:

No, but it may have had them before I owned it.

I don't think so. It did have some kind of speed kit STC installed though.

Looks like someone removed the lower gear doors and the aft fairings. 
 

[Aerospace]

34 minutes ago, PT20J said:

Looks like someone removed the lower gear doors and the aft fairings. 

Hmm, separate from this current issue do you think it's worth tracking down replacements?

[N201MKTurbo]

I think some of the MSE J's didn't come with lower gear doors.

Personally, I wouldn't add them.

[Aerospace]

What does the gear indicator show when the gear is fully up? When I commanded the gear retract, the alarm sounded instantly and the gear unsafe annunciator lit up. I gave it plenty of time to retract, like 20 seconds, and the annunciator, alarm, and barber pole never went away. So I put the switch down and for the life of me it felt like a normal gear extension with the change in drag and speed and attitude and the reassuring soft clunk.

[Aerospace]

1 minute ago, N201MKTurbo said:

I think some of the MSE J's didn't come with lower gear doors.

Personally, I wouldn't add them.

That's what I was thinking. I may buy a lot on a very nice grass strip.

[N201MKTurbo]

1 minute ago, Aerospace said:

What does the gear indicator show when the gear is fully up? When I commanded the gear retract, the alarm sounded instantly amd the gear unsafe annunciator lit up. I gave it plenty of time to retract, like 20 seconds, and the annunciator, alarm, and barber pole never went away. So I put the switch down and for the life of me it felt like a normal gear extension with the change in drag and speed and attitude and the reassuring soft clunk.

When you say the barber pole, do you mean the floor indicator? If it didn't change, the gear wasn't moving.

[Aerospace]

Yes, the indicator on the floor showed diagonal lines. Does that mean the gear is up?

[N201MKTurbo]

16 minutes ago, Aerospace said:

Yes, the indicator on the floor showed diagonal lines. Does that mean the gear is up?

Mine isn't like that, but yours may be. When the gear is down, it should show two horizontal lines that are lined up.

I think you have an issue with your pressure switch. If you hold the button down long enough, the gear should go up. Time is distorted when there is an alarm going off.

[N201MKTurbo]

31 minutes ago, Aerospace said:

That's what I was thinking. I may buy a lot on a very nice grass strip.

Don't add them if you are flying off of grass. One gopher hole and they are all bent up.

[Hank]

25 minutes ago, Aerospace said:

Yes, the indicator on the floor showed diagonal lines. Does that mean the gear is up?

On my C, it's green and says "GEAR DOWN" when down, and is red when up but I forget what it says. The red-and-white barberpole may show in transit, but I've only seen it when my pucks were old and weather was cold and they wouldn't come up the last little bit.

[toto]

1 hour ago, Aerospace said:

Yes, the indicator on the floor showed diagonal lines. Does that mean the gear is up?

Yes.  On my J, a red and white barber pole means "up" and a green "Gear Down" indicator means down.

[Aerospace]

1 hour ago, N201MKTurbo said:

I think you have an issue with your pressure switch. If you hold the button down long enough, the gear should go up. Time is distorted when there is an alarm going off.

Maybe I do, seems logical. Except doesn't that switch, in addition to activating the alarm, also disable the gear from retracting? I'll do the gear swing soon and will know either way, just got back from the affordable airplane jack store (HF). Yours is a '77 right?

33 minutes ago, toto said:

Yes.  On my J, a red and white barber pole means "up" and a green "Gear Down" indicator means down.

Thanks, your '89 may be the same as my '92

 

1 hour ago, Hank said:

On my C, it's green and says "GEAR DOWN" when down, and is red when up but I forget what it says. The red-and-white barberpole may show in transit, but I've only seen it when my pucks were old and weather was cold and they wouldn't come up the last little bit.

Thanks.