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nose gear failure


Billledger

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I have just purchased a vari eze ... after a great frist 30 minute flight landed like a dream but very long. I landed and checked the plane over then got back in for another thrill, on the way to the runway 15 for take off my nose gear failed and my nose hit the ground. no major damage to aircraft but after an inspection I noticed that the grear teath were worn off on the back side (where almost impossible to see without very careful inspection. well anyway ... has anyone else had this or simmilar experance and Where do I get a replacement? Or do I just take it out and bring to a machine shop or something?

 

Thanks for any input

Bill

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As described in the CPs many years ago:

 

I used a severly modified 1/4 Craftsman Ratchet wrench as the UP / DOWN lock for the nose gear handle. This prevents the nose gear from jumping out of over-center. This is a fairly simple modification that uses all the existing handle hardware.

 

Basically, you drill out the center of the 1/4 drive. The gear handle shaft will now go through the ratchet wrench.

 

Remove the original phenolic gear handle bearing that was installed in the instrument panel.

 

Cut the handle off the ratchet wrench. Using a dremel, open up a recess on the pilots side of the instrument panel where the gear handle comes through. The ratchet will fit snugly in this recess and now act as the bearing.

 

The little flipper level for rachet direction should be below the shaft (on the bottom).

 

scratch the exterior of the rachet for flox. Connect the handle, rachet, and drive tubes together to check fit, length, etc.

 

 

Make sure there is good clearence when you turn the handle. Then drill a small hole through the handle shaft and the 1/4 drive. Press a small roll pin into this hole.

 

This now locks the gear handle to the rachet assembly and the handle will now only turn in the direction that the rachet goes. To reverse direction, you need to move the lever on the rachet.

 

You may need to replace the the original drive shaft tube (from the handle to the "U" joint), as the bolt holes may not line up.

 

When your happy that everything fits, flox the hole that the rachet slides into and put it all together. Put the drive shaft bolt in place and one last clearence check. If everthing is OK, then let the flox cure, and your in business.

 

In the future, to remove the handle, you need to remove the small ring clip from the rachet and the handle and 1/4 drive will slide out backwards. Carefull you don't loose the little ball, spring, and rachet paw.

 

 

Waiter

F16 performance on a Piper Cub budget

LongEZ, 160hp, MT CS Prop, Downdraft cooling, Full retract

visit: www.iflyez.com

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You can also get a whole new gear from McMaster-Carr.

 

Under "find products", type "gears". Then select bevel gears. I made my own Brock nose gear assembly many years ago. I got the gear, the worm and the spring assembly from them. The rest of the tube assemblies I had machined.

 

The parts used in the original Brock unit were very common gears.

 

As Wayne has also said, you can turn the gear around.

 

The over center lock is accomplished by the two porkchop looking pieces. The tabs that stick out in dogleg fashion are the limit stops when they touch the crossbar. Removing a small amout of material from the front face of these tabs allows the mechansim more travel before they reach the stop. The result is more over center travel. ( It's deeper into the lock )

 

By a small amount of material I mean about 1/16th at a time and no more than 1/8th.

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thanks for all the help I will be going to the airport to look it over tomorrow. I have not built one of these so all of this info is helpful. I was wondering weither I could just turn the grear around .. and you answered that question.

 

to do this work .. do I take the whole gear out of the plane or do I work on it inside the nose. any pics or help with getting to this gear.

Another question:

I assume that this gear has some sort of gear lock but the only thing that I have done is turn knob till it stops both ways ... I have not ever felt a lock if there is one ... would probally help if I had a schematic of this nose gear althou it does look simple (of course that is looking from the little nose hole :)

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If I remember right, it is just easier to take the whole mechanism out---lots of stuff in there. Take a look at the plans to get yourself oriented.

 

If you had a properly operating overcenter lock, most likely, you did not have the gear all the way around when you were taxiing. This would have been evident by the aircraft being unusually harder to steer on the ground.

 

The teeth on the gear have no capacity to hold up your weight---they are just designed to lift the gear up and down with no weight.

 

If you in fact did have the gear all the way down for taxiing, then it probably jumped overcenter while taxiing----there are many "fixes" for this.

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Bill

 

You will have to remove the gear assembly to get at the bolts that hold the bevel gear on.

 

Here are two drawings that should help. Join the two and you have a complete side view. You should be able to access the assembly from a front battery hatch if you have one. You should be able to get it out without removing the canard. It would be easier if you removed the battery.

 

Since you bought the plane, this area is often used to mount limit switches for gear warnings. Look for these.

 

Once out, carefully check the worm drive assembly. Push it front to back without turning it. To get the worm centered on the bevel, washers may have been used when it was built. I used a phenolic washer that eventually wore out and needed replacement. Make sure there is no end play here. Adjust with washers to take up any extra play.

 

Clean up everything with mineral spirts. You can use wheel bearing grease during re-assembly.

Open-EZ r5 A6.pdf

Open-EZ r5 A7.pdf

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Well .... I took it out yesterday and put it back in. and it worked fine going down .... what i did not do is raise it up all the way ... before I left checked it out one more time. and it would not go all the way up. I didnt have time to check it but I think maybe I didnt align the gear up like I should. On the good note. I at least understand everything better and have more of an understanding of what actually happened. My conclusion is ...... ..... ..... PILOT ERROR :( I think when the wheel touched the ground I felt the resistance and thought that it was all the way down. evedintly it was not and will not make that mistake again! Now my intentions are to get it back to my hanger! I plan to lock the ger down and visually inspect it after put down and fly it 15 min to my home airport and hanger (where all my tools are). working away from your home is not as fun! then make any adjustments there.

 

~Bill

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Bill:

 

I had a very similar exsperience with my old Longeze that I built. I taxied out to do my run up. While taxing the plane sounded like it was making funny noises not enough to keep me from going flying though. I had to taxi almost a mile to get to the run up area. When I throttled up my plane fell onto it nose very abruptly it pushed the nose bumper into the foam and stripped all the teeth off of the gear. It was a long depressing walk back to the hanger. I took the whole gear mechanism out of the plane and turned the cast gear over. Be carefull that you get the load on the brass gear right. I think what happened is that I let the gear drop after I had propped the plane and got it running I think it went down to fast and hit the stop and bounced back out of over center. The taxi ways were very smooth at chino airport so it did not take any real shock until I throttled up the motor and it pushed the nose down braking the gear. It is the weakest spot in the retract mechanism. My cozy Iv that I am presently building has the same mechanism in it. Like waiter said in his post I am going to install the little ratchet mechanism that keeps the gear crank handle from only turning one way. This should act as a lock to either hold your gear up or down locked where you want it to be. STeve Build on

Steve Harmon

Lovin Life in Idaho

Cozy IV Plans #1466 N232CZ

http://websites.expercraft.com/bigsteve/

Working on Chapter 19,21

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Bill,

 

Just a side note and you may have already done or know this, the green foam used in the fuselage construction is a horrible product and easily given to delamination.

 

After a solid drop on the nose it is not unreasonable to suspect possible delamination on the sides and underside of the fuselage.

 

Have a good look over the full length of the fuselage, a bit of tap testing with a quarter as you go wouldn't hurt.

 

Probably be fine but doesn't hurt, it really is an awful foam used in the fuselage.

 

Mick

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Please note that it is blue 3/8" foam in the fuselage. [well at least mine]. I dont know what kind of foam you are referring to, but in these Cozy IV's, that foam assembly with two plies of BID on each side is VERY robust. It is the old config of the NG-30 design with the carry-over battery cut-out that is the weak link.

As a side note there are a several hundred of these planes flying with this 'inferior' foam, as you call it, and they are holding up marvelously for 20 years...not delaminating left and right.

Self confessed Wingnut.

Now think about it...wouldn't you rather LIVE your life, rather than watch someone else's, on Reality T.V.?

Get up off that couch!!! =)

 

Progress; Fuselage on all three, with outside and inside nearly complete. 8 inch extended nose. FHC done. Canard finished. ERacer wings done with blended winglets. IO540 starting rebuild. Mounting Spar. Starting strake ribs.

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I dont know what kind of foam you are referring to,.....

He is referring to the urethane foam that was (is) called out in the plans for both the Vari & Long.(this post relates to a Vari-Eze.)

 

Urethane is used for two reasons:

Resists fuel

Eze to shape.

 

The biggest concern I have about this foam is how it performs in the event you have an electrical fire in the nose.

 

Under the circumstances described, just concentrate on fixing the gear assembly and get it back in the air.

T Mann - Loooong-EZ/20B Infinity R/G Chpts 18

Velocity/RG N951TM

Mann's Airplane Factory

We add rocket's to everything!

4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done

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Edge 513

 

and they are holding up marvelously for 20 years...not delaminating left and right.

Actually they're aren't, and mine which is a fairly well built version and always hangared and 21 years old is testimony to the fact. Others will no doubt confirm the fact that the GREEN urethane foam is a less than an ideal product from a structural perspective. Hence it wasn't used after the VE except for non structural sculpting, ie. nose section of the LE's for example.

 

TMann

 

Under the circumstances described, just concentrate on fixing the gear assembly and get it back in the air.

That would have to be one of the most stupid pieces of advice I have ever read.:irked:

 

Mate, with an attitude like that your going to kill yourself, please fly on your own!!

 

The inspection I refered to would take about ten minutes and is easily performed. This very simple inspection could mean the discovery of an unairworthy aircraft or confirm its airworthiness. It may also highlight pre-existing damage, as it would appear that Bill is new to his machine and this inspection may well have been overlooked in the pre-purchase inspection.

 

Just stop and consider how structualy sound an airframe would be with significant delamination around the nose bulkhead/canard attach area of the fusealage.

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  • 3 weeks later...

Ok I started working on nose gear a few weeks ago.... one thing led to another and before it was over Tim and I have totally went through the whole plane and fixed repaired ...etc everything that looked like it needed it or not. nothing that was making it non airworthy but we did find a lot of areas that we needed to add some fiber glass .... we did redo the area where the nose gear was as it had a crack (looked like it was previously patched before) and reinforced it. It is being re-primed today and will be painted this week. should be up in the air this weekend. Thanks for all the help. I am now much more intimate with this airplane ... it was the best thing that could of happened. now on another note I found a small crack in the prop. any suggestions on props? who to send too for repair and better yet ... any recommendations for a new prop? has anyone used one of those carbon fiber props? will they improve performance that much... or are they overrated?

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TMann

Under the circumstances described, just concentrate on fixing the gear assembly and get it back in the air.

That would have to be one of the most stupid pieces of advice I have ever read.:irked:
:ROTFLMAO: ...... What, are you new here or what?

T Mann - Loooong-EZ/20B Infinity R/G Chpts 18

Velocity/RG N951TM

Mann's Airplane Factory

We add rocket's to everything!

4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done

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i have used the blue/green foam cut-outs as tests now and then to show others how strong this plane is. we jump on them until it fails then i show why it failed then show them how we do the edges so it cant fail, and all will say that there would be no way to hurt the part. now, as per the yellow foam or the home-depo pink stuff...............not so good:bad:

Steve M. Parkins

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TMann

 

What, are you new here or what?

New-ish I guess.

 

About 800 hrs on the VE in the last 10 years.

 

My comments on urethane foam stem from experience/knowledge gained working in a commercial sailplane maintenance facility for 2 years + ownership of the VE for 10 years.

 

I stand by my comments!

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