Bud
Wow, thanks for a very thorough answer, I have a longer list for my
next inspection.
Jerry
Sent from Iphone
On Jul 15, 2010, at 5:26 PM, "Bud Yerly" <budyerly@msn.com> wrote:
> Jerry,
> You are not alone and not living dangerously, as it seems you have a
> well built reliable gear. However the non mandatory mod 51 arm
> helps keep the stress down on the three bolts in the retraction
> arm. Eventually, through trailering, rough air, rough airstrips and
> countless landings you may experience trouble. If the arm flexes at
> the connection to the LG08 it may be difficult to lower the gear and
> it may require you to unload the aircraft to near negative G to flop
> the gear handle out of the slot. On takeoff, you may find that the
> gear will not lock up properly. Extending the gear may leave the
> LG08 mechanism at less than vertical. Looseness at this joint will
> progress rapidly through normal use as the gear has no over center
> lock per say and will bend at its pivot points slightly both up and
> down, exacerbating the problem.
>
> Even with mod 51, if the gear is not perfectly vertical from LG8
> down, the gear handle takes the load. That dog leg in the gear
> handle with the bends will flex over time, causing a higher than
> anticipated tension load on the Mod 51 diagonal brace. We'll have a
> material and proper dimensions to use for the arm soon. We all used
> Home Depot aluminum on previous builds and I should have questioned
> it, but I fly a trigear and rarely get a monowheel of significant
> age in the shop. No one reported the problem so it was unknown to
> me until now.
>
> I would recommend one look at his retractable gear carefully on his
> annual, and at 5 years or 500 landings do a full inspection and
> rebuild. Call me conservative in a liberal world, but the bushings
> and landing gear block take a beating and are never cared for (I
> hate that dirty hole..). All the retractable gear certified planes
> I have experience with require not just a retraction check but a
> complete check of the bearings and bushings annually, slop and play
> are defined in the maintenance manual for the aircraft. Why
> shouldn't we do the same thorough inspections and replace known wear
> points at a specific time to preclude future problems.
>
> Klaus and I discussed time changing out the following:
> At 5 years or 500 landings,
> Replace the bungee.
> Wheel bearings KLNJ 1 1/2 They are sealed bearings, and I haven't
> seen a failure but why wait until they break.
> Brake pads (inspect caliper for corrosion)
> Upper and lower bushings AIC 060816/AIC 060820. Inspect annually for
> play and replace if detected and replace at 5 years anyway.
> Inspect Mod 51 arm for wear and replace as necessary
> Inspect shock absorbers and rubber block. If it hops like a bunny,
> change the shocks, if it sits low, change the block. I don't know
> how low, low is, but the block is about 70mm on an empty mono, so
> if it has lost 10 mm in height since new, it probably needs replacing.
> Look at the long bolts Euro 26 and pins LG 04 for deformation,
> replace as necessary
> Change the outrigger legs, inspect the pivot points and the locking
> mechanism for corrosion and wear. Remove and replace as necessary.
> Replace the outrigger tires/wheels if worn.
>
> I do not have a checklist for how I check the mono gear for play,
> and frankly just look at the mechanics as I do not own one... I
> support the aircraft, push on the lower arm and watch the mechanism
> when down, especially the locking arm. Look at the LG 04 pin and
> support for cracks and wear. Any deformations of the gear requires
> replacement. Then partially retract the gear and check for play in
> the joints, wiggle the arms to check for play, and pivot points for
> play (nasty dirty job), and finally lock the gear up and check
> movement of the gear mechanism by pushing up on the gear and using
> my bore scope to see if there are problems. I have never removed
> the mod 51, but I have also never worked on a high time mono. As
> for the outriggers, I have to look at the book if I have to take one
> apart just to figure how to put it back together. I make sure that
> the gear leg locks down and that the flap moves through the proper
> number of degrees before unlock. I was not familiar with the Europa
> Club bushing mod many of you had on the outriggers until Jim Butcher
> led me through one. I have only seen the standard factory build.
> If there is a comprehensive checklist other than the FAA condition
> inspection, I'd like to see one for my own education.
>
> Sorry to be so long winded.
>
> Bud Yerly
> ----- Original Message -----
> From: Jerry Rehn
> To: europa-list@matronics.com
> Sent: Tuesday, July 13, 2010 9:18 PM
> Subject: RE: Europa-List: Check your Landing Gear Retraction Lever
> Strut (Mod 51)
>
> Bud
>
> I have not installed Mod 51 and have been flying with lots of
> landings for 10 years, am I living dangerously? I check the gear and
> don't see issues but am I missing something? Am I the only one with
> out Mod 51?
>
> Jerry
>
> Mono 914
>
>
> From: owner-europa-list-server@matronics.com [mailto:owner-europa-
> list-server@matronics.com] On Behalf Of Bud Yerly
> Sent: Tuesday, July 13, 2010 5:17 PM
> To: europa-list@matronics.com
> Subject: Re: Europa-List: Check your Landing Gear Retraction Lever
> Strut (Mod 51)
>
>
> Klaus and others,
>
> Please send me pictures of your elongations or failures of the strut
> for me to analyze. If you can provide the type material and
> thickness also.
>
> Normally 6061 common aluminum angle of 1.6 mm or 1/16 inch is plenty
> strong enough.
>
> Elongation of the hole at the bottom indicates slight movement of
> the gear lock ,retraction mechanism (most probably in the down
> position) due to not staying perfectly vertical with the gear down
> and eventually the stresses from bending, as Klaus said, or from the
> latch slot gear retraction arm interface bending, and or the three
> bolts elongation has caused fatigue of the material or too much
> force on the aluminum angle strut.
>
>
> We will need some look see time to evaluate should if we go to steel
> or a specific material/dimensions, time change, or what.
>
>
> In the mean time, if everyone can look at their Mod 51 landing gear
> retraction lever strut brace if over say 500 hours and look for
> wear, as soon as you can, and low time planes on your next annual,
> then send me updates, I'd appreciate it.
>
>
> Many thanks,
>
>
> Bud Yerly,
>
> Europa Tech Assistance.
>
> direct email: budyerly@msn.com
>
> or just hold control key and click below to email
>
> via Europa website: mailto:enquiries@europa-aircraft.com
>
> via Custom Flight Creations website: mailto:mail@customflightcreations.com
>
>
> ----- Original Message -----
>
> From: klaus dietrich
>
> To: Europa-List Digest Server ; jimmy Keppert
>
> Sent: Tuesday, July 13, 2010 1:29 PM
>
> Subject: Europa-List: Check your Landing Gear Retraction Lever Strut
> (Mod 51)
>
>
> Check your Landing Gear Retraction Lever Strut (Mod 51)
>
> after 10 years in service and some 800 hours with as many landings,
> my Landing Gear Retraction Lever Strut (Mod 51) had an oval oversize
> hole at the bottom end (14mm; for the MS 20392-5C37 bolt which is
> 9,5 mm) and it finally broke at the top (just below the AN 3 bolt
> probably due to some misalignment due to the play at the bottom...
> no play at the top AN 3 bolt, however!
>
> The three screws on the Landing Gear Retraction Lever at the top
> seem to hold (no play)....
>
> I'm still searching for an explanation; my aluminum angle was
> probably not strong enough: material thickness: 1,5 mm; L-profile:
> 20 mm x 8 mm
> also the strut is not absolutely straight and there is some sideways
> flexibility which may have favored the play...
>
> Klaus
>
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