Nose gear shock absorber

[M20 Ogler]

My C still has it. Should it get removed? I’ve not seen one on any other Mooney before and did not know they were a thing until I saw my plane for the first time. 

[Shadrach]

I think it probably improves the nose gear performance to some degree. Whether it’s noticeable or not is debatable. You could always remove it and then reinstall. I ordered a new truss from LASAR over a decade ago so I had no choice in removing mine.

[N201MKTurbo]

If you are taxiing over a rough surface, the nose will sometimes get into this resonant bounce. The shock will stop it. The bounce doesn't hurt anything. Most people take it off and gain about 5 Lbs. of useful load. Mooney quit putting them on.

[RLCarter]

Isn’t there a bulletin to remove it?

[1964-M20E]

Go ahead and remove it.   It is one of those extra parts that always work their way into machinery or left over when assembling your kid's toys 

[Andy95W]

Shock Removal.pdf

It's actually an Engineering drawing that allows removal. 

Edited July 6, 2021 by Andy95W

[carusoam]

1) It weighs a lot…

2) It probably works for a few years…

3) It probably stopped working a few years ago…

4) Most have been removed…

5) Keeping the nose gear maintained keeps the need for this device to a minimum….

6) If you get a nose wheel flutter while on the ground… aka the eight second ride… there is a procedure to check for wear, and properly set the nose gear…

PP thoughts only, not a mechanic…

Best regards,

-a-

[Mooneymite]

I thought mine was the last C in America to still have the damper installed.  I guess not.

Half my landings are on our turf runway, so I believe that the nose damper is advantageous.  I should probably remove it and see if it actually makes a discernible difference.

[Shadrach]

5 hours ago, Mooneymite said:

I thought mine was the last C in America to still have the damper installed.  I guess not.

Half my landings are on our turf runway, so I believe that the nose damper is advantageous.  I should probably remove it and see if it actually makes a discernible difference.

I think that the damper definitely offers an advantage on turf. I can’t imagine how having a damper would not be advantageous. The only evidence I have is seeing the difference in how my nose gear now reacts going over a parking chock. It compresses and slams back to full extension. Seems that it would be preferable to have something smoothing that tendency out on unimproved surfaces.  I wouldn’t call 2.1lbs heavy @carusoam but every bit helps.

My guess is that Mooney discontinued the damper not because it does not work but because under the vast majority of Mooney operations, smoothing out shock oscillations is not needed. If you’re running on turf, it’s probably kinder to the gear components to have one installed

Edited July 6, 2021 by Shadrach

[EricJ]

2 hours ago, Shadrach said:

I think that the damper definitely offers an advantage on turf. I can’t imagine how having a damper would not be advantageous.

I think it's just a tradeoff between the benefit and the added weight/maintenance.    There is definitely a benefit to having them, I think there's just generally been a lot of opinion that the benefit is small compared to the downsides.

I've made some funky landings where it sat it on the mains and then the nose bounced a couple of times when it came down.   That's a downside of the rubber-donut suspension;  it has very little damping compared to strut suspensions.   The damper is there to reduce that bounce.  

 

[Raymond J1]

Necessary on irregular grass track, I keep it just for this job.

 

Edited July 6, 2021 by Raymond J

[Mooneymite]

2 hours ago, EricJ said:

I think it's just a tradeoff between the benefit and the added weight/maintenance. 

Is there specified maintenance?

I've never done a thing to the damper, if there is something I need to be doing, point me to the source, please.

I will say that the damper mounting lugs were really, really helpful when I replaced my nose gear doughnuts using a turnbuckle for some of the compression.

[EricJ]

2 minutes ago, Mooneymite said:

Is there specified maintenance?

I've never done a thing to the damper, if there is something I need to be doing, point me to the source, please.

I will say that the damper mounting lugs were really, really helpful when I replaced my nose gear doughnuts using a turnbuckle for some of the compression.

If it stops damping, it needs maintenance.   Wear is normal on dampers, whether they're hydraulic or friction based.   Take it off and see whether it resists motion in both directions.    If not, it needs maintenance as it is no longer damping.   If it isn't damping the only thing it's doing is adding weight to the airplane.

 

Edited July 6, 2021 by EricJ

[Shadrach]

3 hours ago, EricJ said:

 That's a downside of the rubber-donut suspension;  it has ABSOLUTELY NO damping compared to strut suspensions.   The damper is there to reduce that bounce.  

 

Fixed it for you!

[Shadrach]

3 hours ago, Raymond J said:

Necessary on irregular grass track, I keep it just for this job.

 

Not necessary for grass but better. Most of the grass that I land on is <2000’ so most touchdown are on the firmer side.

[PT20J]

My 1978 J had one; my 1994 J does not. Due to the geometry of the main gear, Mooneys tend to be nose heavy when resting on the mains, and on landing the nose wheel can come down fairly hard sometimes depending on touchdown speed, deck angle and sink rate at touchdown. I found the shock absorber made the nose wheel touch down softer.

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