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Mooney gear up at my home field today


yvesg

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Hi, Anthony. No. THE spring is an Eaton/Avionic Products/Plessey actuator issue, as installed in Mooneys from 1978 on. This thread relates to Duke actuator equipped Mooneys built in 1977 and before. The accident aircraft is apparently a '77 J.

That is a Duke actuator on the picture.

You can search for the Mooney SB20-282 for info and plenty of illustrations on the no- back spring.

Mostly on Eaton actuators. eaton actuators may be on any serial number including early Js ( although the factory started installing them after 78).

The SB is very informative.

Most SB are actually informative even when they don't need to be complied with.

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That is a Duke actuator on the picture.

You can search for the Mooney SB20-282 for info and plenty of illustrations on the no- back spring.

Mostly on Eaton actuators. eaton actuators may be on any serial number including early Js ( although the factory started installing them after 78).

The SB is very informative.

Most SB are actually informative even when they don't need to be complied with.

Are you sure it is SB20-282? There is a SB20-282a about avionics on the mooney site...

Yves

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Are you sure it is SB20-282? There is a SB20-282a about avionics on the mooney site...

Yves

SB20-282 was the first one I believe. There are subsequent ones, revisions , updates , etc ....  That's why some called it the no back spring fiasco 

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I had to put one down on its belly once when the gear wouldn't extend.  The thought of trying to get the prop stopped did cross my mind but in the end the risk of complicating an already stressful situation did not seem like a good idea.  I kept telling myself - fly the plane and don't make a bad situation worse.

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My gear failed to lower using the emergency system at annual a month or so ago....I have the Eaton actuator on my J...the culprit was the brass clutch which cost $432 from the factory....I discovered it on a Monday afternoon here in rural Scotland and I had the replacement in my hand by Wed lunchtime....excellent service from Steve and Ruth at the factory! Anyway for the Eaton it sounds like a similar failure mechanism to the. Dukes described above.....if the clutch is partially engaged due to badly rigged engagement cable/spring the spline will partially engage during normal operation and you won't necessarily know...but all the while it is rounding the square hole in the clutch...until eventually the clutch will not turn the shaft....see pics of the actuator...and the offending clutch....a call to Don Maxwell helped confirm the diagnosis before pulling it apart....there was no need to remove the entire actuator...just remove the back end

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Why is foaming a runway a bad idea.

1. Not necessary. There are many GU landings caught on video. Has there ever been one where the aircraft caught fire? I honestly can't remember any.

2. Because most guys end up missing it.

3. Potentially very expensive. I understand that if the airport offers it, they pay for it. If you request it, you pay for it. I have heard that it's not cheap and the insurance companies won't pay for it. 

 

Would I request it? No. Would I accept it if they offered it to me? Probably. 

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A little related to this topic:

 

When I stop my engine,  I notice that the prop always stop in the vertical position.

Your prop may be improperly "clocked". I can't tell what model you fly, but if it's got a 4-banger, the prop typically does not stop vertical. Simple to re-clock if you like safety wiring things. :-)

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Sadly, this failure is one of the very few serious problems that affect the vintage planes that have electric gear. The stripped shaft is no longer in production, so there are no new parts. Used ones are very scarce because the problem is somewhat common. The Mooney factory solution is to upgrade you to the newer system at a cost of $12,000 I think. At this point you will have to call every salvage yard you can find and then, start networking here and on the MAPA list to find somebody who is parting out a plane that has a usable one. Unfortunately, without it, your plane is unairworthy and grounded. 

 

I know all this because I bought my plane from a bank. It was a repo. Before the plane was sold, the bank performed an annual on the plane by a shop that while is not a Mooney specialist, I think it is not a bad shop. They discovered that my plane also had a stripped shaft on the emergency deployment mechanism. That shop scoured the country for that part and bought what they believed at the time to be the only one available in the States for... something like $3500 for one tiny, ordinary looking used part. Thankfully it was the bank's dime, not mine. I suspect at annual, some IAs feel sorry for the owners and look the other way.

 

To the OP- you may have to get creative. You may have to consider buying one of these rotten hangar rats we see popping up with seeming regularity here on this sight, just to get that little part. Then sell the engine, prop and maybe some avionics to cover the rest. So if you see a project plane that has been sitting come up, check it out. That stupid little part you need so much might actually be OK.

 

This is one situation where I really feel so very, very sorry for the Mooney poor owner. While the insurance company will pay you for the gear  up damage, they are not likely to pay for the part that actually caused the gear up because it is a mechanical failure and not an accident.

 

Good luck and check here often. Someone will likely point you the right way.

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Seems like a simple enough part to turn out on an CNC I guess I should get busy and start making some chips.

Actually it is a tiny simple looking part. But kind of complex. The only war to make it would be with a broach or wire EDM..

I bought one about five years ago it took about a month to find it and it cost $500.00. I was told it was the last one on the planet.

Luckily I work at a place with a wonderful machine shop. If I was to give the foreman the damaged part, sometime that day he would give me a new part.

Don't ask me to play that card. I already owe him too much.

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Sadly, this failure is one of the very few serious problems that affect the vintage planes that have electric gear. The stripped shaft is no longer in production, so there are no new parts. Used ones are very scarce because the problem is somewhat common. The Mooney factory solution is to upgrade you to the newer system at a cost of $12,000 I think. At this point you will have to call every salvage yard you can find and then, start networking here and on the MAPA list to find somebody who is parting out a plane that has a usable one. Unfortunately, without it, your plane is unairworthy and grounded. 

 

I know all this because I bought my plane from a bank. It was a repo. Before the plane was sold, the bank performed an annual on the plane by a shop that while is not a Mooney specialist, I think it is not a bad shop. They discovered that my plane also had a stripped shaft on the emergency deployment mechanism. That shop scoured the country for that part and bought what they believed at the time to be the only one available in the States for... something like $3500 for one tiny, ordinary looking used part. Thankfully it was the bank's dime, not mine. I suspect at annual, some IAs feel sorry for the owners and look the other way.

 

To the OP- you may have to get creative. You may have to consider buying one of these rotten hangar rats we see popping up with seeming regularity here on this sight, just to get that little part. Then sell the engine, prop and maybe some avionics to cover the rest. So if you see a project plane that has been sitting come up, check it out. That stupid little part you need so much might actually be OK.

 

This is one situation where I really feel so very, very sorry for the Mooney poor owner. While the insurance company will pay you for the gear  up damage, they are not likely to pay for the part that actually caused the gear up because it is a mechanical failure and not an accident.

 

Good luck and check here often. Someone will likely point you the right way.

Thanks Dave. Just to make things clear, I am the original poster but just a friend of the poor fellow who had the gear-up ordeal in Gatineau on Monday. It went pretty close that I would be partner with him on a Mooney at some point but it did not happen. It could have been this same aircraft.

I will contact him and let him take a look at this thread. All this information can surely help his mechanic. Thanks to all for your help. After looking at all this, the wife is really happy our bird has the Johnson bar.

Yves

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Actually it is a tiny simple looking part. But kind of complex. The only war to make it would be with a broach or wire EDM..

I bought one about five years ago it took about a month to find it and it cost $500.00. I was told it was the last one on the planet.

Luckily I work at a place with a wonderful machine shop. If I was to give the foreman the damaged part, sometime that day he would give me a new part.

Don't ask me to play that card. I already owe him too much.

 

It is the sort of part that needs a free, public CAD file, or drawings with specs for the metal so that an owner could easily get the part produced locally and legally. This is an area that I wish the new MAC would help with. If they don't want to make the parts anymore, publish the plans so we can make them.

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You would have the Dukes actuator, the same as my plane with the crank on the side wall.

It is real easy to accidentally engage the emergency retract mechanism. If it is engaged and you try to raise or lower the gear the crank handle will spin around real fast and then stop. When it stops you have just sheared the splines out of the disconnect coupling. That coupling is very hard to find.

I had one of the brushes come loose and fall out of my actuator motor once so it stopped working. Luckily my emergency system worked.

^ ^ ^ ^  This!

 

I had some avionics service done on my '77 J.  

 

Unfortunately,  what I thought was a very thorough pre-flight missed the fact that someone at the shop bumped the manual gear engagement lever over as they were under the panel.

 

It wasn't on my checklist and is not obvious down past my knee from the pilot's position.

 

Net result on the 1st gear retraction was as described, with the added bonus of the aluminum Dukes case splitting open and dumping the gear set after something bound up.

 

Gear dangling, both the electric and manual gear extend no-worky, and I ended up with a belly landing (no foam.)

 

There is now one more item checked after anyone other than me is in the plane!

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I know that on my annual two years ago my mechanic found that my emergency gear extension was well past worn (1983 M20K).  It took some doing but he found the replacement part.  I do not think that if my mechanic did not have 25 years plus working on Mooney's and had been factory trained that he would have found the problem.  Just goes to show you that you really do need a Mooney expert working on your plane.  The Mooney is not your average plane for just any A&P.  Just take a look at the flight control rigging.  It is an art and requires special know how and tools to do it right.  By the way, whoever did this gear up landing did a great job.  Well done.

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This sounds terrible. I didn't realize that if the Duke's Gear actuator spline fails, the manual mechanism no longer works. That is troubling.

 

Re: Duke's:  Is there a service bulletin that describes all that typically goes wrong with the Duke's actators?  So far I have heard (from above):
1) The disconnect spline (I guess) shearing off  (or was it stripping of the spline?).

2) An electric motor brush falling out.

 

You guys have me worried. I just put a new big-bore 390 motor and scimitar prop in my '69 E and had it painted too. 

John

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^ ^ ^ ^  This!

 

I had some avionics service done on my '77 J.  

 

Unfortunately,  what I thought was a very thorough pre-flight missed the fact that someone at the shop bumped the manual gear engagement lever over as they were under the panel.

 

It wasn't on my checklist and is not obvious down past my knee from the pilot's position.

 

Net result on the 1st gear retraction was as described, with the added bonus of the aluminum Dukes case splitting open and dumping the gear set after something bound up.

 

Gear dangling, both the electric and manual gear extend no-worky, and I ended up with a belly landing (no foam.)

 

There is now one more item checked after anyone other than me is in the plane!

 

I now put a piece of lock wire with loops twisted in the ends holding the lever in the disengaged position. It is like a beefy twist tie.

 

If I need to use the emergency extension I remove the lock wire and then engage the crank.

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I now put a piece of lock wire with loops twisted in the ends holding the lever in the disengaged position. It is like a beefy twist tie.

If I need to use the emergency extension I remove the lock wire and then engage the crank.

instead of using lock wire use shear wire, does the same thing but allows you to easily break it in an emergency instead of trying to divide your attention and remove the lock wire.

Brian

Sent from my iPad using Tapatalk

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This sounds terrible. I didn't realize that if the Duke's Gear actuator spline fails, the manual mechanism no longer works. That is troubling.

 

Re: Duke's:  Is there a service bulletin that describes all that typically goes wrong with the Duke's actators?  So far I have heard (from above):

1) The disconnect spline (I guess) shearing off  (or was it stripping of the spline?).

2) An electric motor brush falling out.

 

You guys have me worried. I just put a new big-bore 390 motor and scimitar prop in my '69 E and had it painted too. 

John

 

The electric motor will eventually wear out (happened to me) but so long as your emergency system is up to par it is not an emergency.  The failure mode there is if the emergency engagement system is mis-rigged such that the two mating splines are kissing and not completely apart.  The kissing connection will ruin the ends of the splines, making engagement impossible when you need it.  Check it at every annual when you inspect & lube the actuator.  Don't worry too much.  :)

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instead of using lock wire use shear wire, does the same thing but allows you to easily break it in an emergency instead of trying to divide your attention and remove the lock wire.

Brian

Sent from my iPad using Tapatalk

 

I thought of that, but I didn't have any. Besides, I didn't want it to break. My Ex-partner would have found a way to break it with his knee.

 

Either way removing the lock wire isn't hard. Much easier then turning the crank the 1000 turns or so that it takes to lower the gear!

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I now put a piece of lock wire with loops twisted in the ends holding the lever in the disengaged position. It is like a beefy twist tie.

 

If I need to use the emergency extension I remove the lock wire and then engage the crank.

 

What does the wire connect to?

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