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fklein(at)orcasonline.com
Guest

Posted: Tue Oct 13, 2009 10:13 pm Post subject: Mod 73

With the premise that the only stupid questions are those which aren't  

asked, I have a couple for anyone who'd like to comment on this Mod 73.



As I recall, Mod 73 is a direct outcome of the initial concerns  

following William Mills' tragic in-flight break up...particularly a  

concern that the triggering event was one of the tailplanes moving  

outboard and decoupling from the pins on the torque tube flange.  

Following the grounding of UK-based Europas, Mod 73 was devised,  

approved, and implemented on the entire UK fleet as well as on many  

other aircraft based elsewhere. From the list prepared of those who  

implimented Mod 73 (I don't believe) any instances were discovered or  

reported of incipient failures.



Subsequently, the accident investigation (if I recall correctly)  

determined that the triggering event was a failure caused by the  

incorrect location of embedded aluminum plates on the inboard face of  

a flap...a condition which precluded the proper threading for the flap  

pin which was pulled free and destabilised the aircraft...a condition  

totally unrelated to issues intended to be addressed by Mod 73.



If I am even partially incorrect thus far, please enlighten me.



So my questions are:



- Is Mod 73 a required mod for any aircraft based outside of the  

UK?...particularly in the US?



- If not, why implement Mod 73 when there is no evidence that a  

problem with the original design exists?



- Is Mod 73 an example of a prematurely arrived at "fix", approved and  

implemented in a rush to get the Europa fleet airborne again before  

the real culprit was determined...and...does it remain in effect today  

out of a reluctance of regulatory agencies to set things right?



Thanks for any comments and input,



Fred

A194

frans(at)paardnatuurlijk.
Guest

Posted: Tue Oct 13, 2009 11:27 pm Post subject: Mod 73

Fred Klein wrote:



 	  Quote: 	
		   why implement Mod 73 when there is no evidence that a problem

 with the original design exists?


	


Because it makes sense. The changes imposed by mod 73 enhance the safety

of the aircraft. The pip pins are intended to hinder outboard movements

of the tail plane, not to take over torque loads. So changing the design

so that the parts involved can only do what they are supposed to do, and

nothing else, is a valuable improvement.



Whether a real accident has happened or not is not really my concern.

The good thing about the accident was that is was a reason to look again

with an eagle eye to the design of the Europa, and to correct any

(theoretical) flaws. Mod 73 was a result of that.



Frans

jonsmitheuropa(at)tiscali
Guest

Posted: Wed Oct 14, 2009 12:04 am Post subject: Mod 73

Hi, I'm very happy to have completed this mod, if only for peace of mind.  Whether or not the pre-mod design was actually a contributing factor to the failure or not may never be known for sure but the mod is a good one and I am now happy in my mind that it is certainly not possible for that potential problem to occur in the future.  Any improvement in design is good in my book.



BTW, the wing failure and the addressing mod (74) was the rear wing root pin (that takes the pip pin), not the flap pin.



Cheers, Jon

Visit -  www.EuropaOwners.org

johnwigney(at)windstream.
Guest

Posted: Wed Oct 14, 2009 8:43 am Post subject: Mod 73

Regarding the tailplane retention issue, I attach some photos below of a 

modification which precludes any chance of the tailplane becoming 

detached. I think they are self explanatory. For those who get the 

digest and have these photos stripped off, let me know if you are 

interested and I can send them direct. This design is not mine and came 

from Europe - my compliments to the original designer, I do not have a 

record of his name. The end plug idea prevents enthusiastic helpers from 

damaging critical components.



Cheers



ORIGINAL MESSAGE



From: Fred Klein <fklein(at)orcasonline.com>

Subject: Mod 73

With the premise that the only stupid questions are those which aren't  

asked, I have a couple for anyone who'd like to comment on this Mod 73.

As I recall, Mod 73 is a direct outcome of the initial concerns  

following William Mills' tragic in-flight break up...particularly a  

concern that the triggering event was one of the tailplanes moving  

outboard and decoupling from the pins on the torque tube flange.  

Following the grounding of UK-based Europas, Mod 73 was devised,  

approved, and implemented on the entire UK fleet as well as on many  

other aircraft based elsewhere. -------------

europabill(at)bellsouth.n
Guest

Posted: Wed Oct 14, 2009 10:14 am Post subject: Mod 73

John,



Can you send again?  Didn't see any pictures...



Thanks,



Bill

A010 Europa Monowheel Classic

---

rlborger(at)mac.com
Guest

Posted: Wed Oct 14, 2009 10:25 am Post subject: Mod 73

John,



How 'bout posting them on the Europa Owners site.  Appropriate place would be a sub album in the "Builders photo album."



Thanks,

Bob Borger

 

On Wednesday, October 14, 2009, at 11:25AM, "John & Paddy Wigney" <johnwigney(at)windstream.net> wrote:

 	  Quote: 	
		  



Regarding the tailplane retention issue, I attach some photos below of a 

modification which precludes any chance of the tailplane becoming 

detached. I think they are self explanatory. For those who get the 

digest and have these photos stripped off, let me know if you are 

interested and I can send them direct. This design is not mine and came 

from Europe - my compliments to the original designer, I do not have a 

record of his name. The end plug idea prevents enthusiastic helpers from 

damaging critical components.



Cheers

budyerly(at)msn.com
Guest

Posted: Wed Oct 14, 2009 10:51 am Post subject: Mod 73

<?xml:namespace prefix="v" /><?xml:namespace prefix="o" /><![endif]-->  Fred,

 Here is my two cents as an average builder:

 Question 1

 - Is Mod 73 a required mod for any aircraft based outside of the   

UK?...particularly in the US?



 My Comment:

 The US declares you are the builder of the aircraft.  You may modify  or choose not to modify your kit...It is your decision as the builder, as the  kit manufacturer is a 49% helper, but you are the builder.  Just as if  you built the plane from scratch.  It is highly recommended that all  ADs/mandatory actions directed by your kit manufacturer be  followed.  If the UK's PFA or LAA grounds their planes, technically you  don't have to ground your experimental, but as some kit manufacturers  have found, the FAA can ground a kit if it believes losses are  occurring due to design problems or recommended/directed construction  procedures...  Your plane is an experimental, each is technically different  and the rules for FAA involvement in monitoring the accidents, as in certified  aircraft, does not receive the same scrutiny...  SLSA/ELSA have different  rules like certified aircraft.

  

 Question 2

 - If not, why implement Mod 73 when there is no evidence that a   

problem with the original design exists?



 My comment:  This is a builder/maintainer issue.  All builders  are not created equal nor is care always taken putting the tailplanes on and  off.  Occasionally, the tailplanes are never taken off and rust  on.   When taken off for inspections, so much force is used, the inner  and or outer bearing may be loosened and or broken loose and missed by the  owner.  I have also seen that in their maintenance exuberance, owners  have sprayed oil into the stab holes and melted all the foam away from  the bearings leaving only glass to support the outer bearing.  Believe it  or not some of the pip pin holes are so sloppy, pins can fall out and other  methods are used to secure the pin and tail plane...  

  

 If built and maintained properly, you may never have a problem, but the Mod  73 tailplane mod, adds extra glass and support to ensure your outer bearing is  solidly glassed and in fact glassed more solidly.  Down side is you may  need a longer pip pin.  Oh well.  Go to McMaster Carr.

  

 Question 3

- Is Mod 73 an example of a prematurely arrived at "fix",  approved and  

implemented in a rush to get the Europa fleet airborne  again before  

the real culprit was determined...and...does it remain in  effect today  

out of a reluctance of regulatory agencies to set things  right?



 Comment:

 Yes and no.

 It is a quick and necessary bandaid to get the fleet flying abroad and  properly inspect the fleet.

 I would prefer to see all of us to use the Europa Club mod of a tube of  glass supporting both bearings.  This is a great mod, in my opinion, and  should be the standard.  The NG control surfaces bond in the bearings much  more securely...Dare I say properly.  But the bandaid of outer bearing  reinforcement is a great way of getting more support around the bearing and  checking the fleet.  

  

 The problem with the accident investigations is the cart and horse.   What caused Williams accident for sure?  He had two problems, both should  have been caught and fixed during the build and through subsequent  inspections.  The tail plane wobble is a point I harp on constantly, that  the stab should have no movement when attached.  Yes, I disagree with  wallowing out the tube to allow the movement.  Andy and I have never  seen eye to eye on this, but it doesn't hurt anything and should flutter  begin, the outer bearing is free to move a little.  Dare I say any  flutter is BAD, and now you see why I disagree. 

  

 I have only found two flying aircraft with tailplane bearings broken  here at the shop.  But I have done all the tailplanes IAW the mods,  because I believe it makes for a better product, and it is easy to sell a plane  with all the mods properly documented.

  

 As an accident investigator in a prior life, we all die a little when we  loose a fellow aviator.  It is our mission not to bury our loss by saying  it can't happen to me, but to try to make the aircraft, procedures, or  training better to save not just ourselves, but others who come after us so they  don't have to experience our loss.  

  

 Just my thoughts.

  

 Bud Yerly

  

 [quote] [b]

jeff(at)rmmm.net
Guest

Posted: Wed Oct 14, 2009 11:36 am Post subject: Mod 73

Well said Bud!!!



Jeff Roberts

Eagleville Marketing Group / www.eaglevillemarketing.com



615-355-7575 Office

615-406-8651 Cell

615-534-1082 Fax

"Not Advertising to save money is like stopping your clock to save 

time."



On Oct 14, 2009, at 12:42 PM, Bud Yerly wrote:



 	  Quote: 	
		   Fred,

 Here is my two cents as an average builder:

 Question 1

 - Is Mod 73 a required mod for any aircraft based outside of the 

 UK?...particularly in the US?

 My Comment:

 The US declares you are the builder of the aircraft.  You may modify 

 or choose not to modify your kit...It is your decision as the builder, 

 as the kit manufacturer is a 49% helper, but you are the builder.  

 Just as if you built the plane from scratch.  It is highly recommended 

 that all ADs/mandatory actions directed by your kit manufacturer be 

 followed.  If the UK's PFA or LAA grounds their planes, technically 

 you don't have to ground your experimental, but as some kit 

 manufacturers have found, the FAA can ground a kit if it believes 

 losses are occurring due to design problems or recommended/directed 

 construction procedures...  Your plane is an experimental, each is 

 technically different and the rules for FAA involvement in monitoring 

 the accidents, as in certified aircraft, does not receive the same 

 scrutiny...  SLSA/ELSA have different rules like certified aircraft.

  

 Question 2

 - If not, why implement Mod 73 when there is no evidence that a 

 problem with the original design exists?

 My comment:  This is a builder/maintainer issue.  All builders are not 

 created equal nor is care always taken putting the tailplanes on and 

 off.  Occasionally, the tailplanes are never taken off and rust on.   

 When taken off for inspections, so much force is used, the inner and 

 or outer bearing may be loosened and or broken loose and missed by the 

 owner.  I have also seen that in their maintenance exuberance, owners 

 have sprayed oil into the stab holes and melted all the foam away from 

 the bearings leaving only glass to support the outer bearing.  Believe 

 it or not some of the pip pin holes are so sloppy, pins can fall out 

 and other methods are used to secure the pin and tail plane... 

  

 If built and maintained properly, you may never have a problem, but 

 the Mod 73 tailplane mod, adds extra glass and support to ensure your 

 outer bearing is solidly glassed and in fact glassed more solidly.  

 Down side is you may need a longer pip pin.  Oh well.  Go to McMaster 

 Carr.

  

 Question 3

 - Is Mod 73 an example of a prematurely arrived at "fix", approved and 

 implemented in a rush to get the Europa fleet airborne again before 

 the real culprit was determined...and...does it remain in effect today 

 out of a reluctance of regulatory agencies to set things right?

 Comment:

 Yes and no.

 It is a quick and necessary bandaid to get the fleet flying abroad and 

 properly inspect the fleet.

 I would prefer to see all of us to use the Europa Club mod of a tube 

 of glass supporting both bearings.  This is a great mod, in my 

 opinion, and should be the standard.  The NG control surfaces bond in 

 the bearings much more securely...Dare I say properly.  But the 

 bandaid of outer bearing reinforcement is a great way of getting more 

 support around the bearing and checking the fleet. 

  

 The problem with the accident investigations is the cart and horse.  

 What caused Williams accident for sure?  He had two problems, both 

 should have been caught and fixed during the build and through 

 subsequent inspections.  The tail plane wobble is a point I harp on 

 constantly, that the stab should have no movement when attached.  Yes, 

 I disagree with wallowing out the tube to allow the movement.  Andy 

 and I have never seen eye to eye on this, but it doesn't hurt anything 

 and should flutter begin, the outer bearing is free to move a little.  

 Dare I say any flutter is BAD, and now you see why I disagree. 

  

 I have only found two flying aircraft with tailplane bearings broken 

 here at the shop.  But I have done all the tailplanes IAW the mods, 

 because I believe it makes for a better product, and it is easy to 

 sell a plane with all the mods properly documented.

  

 As an accident investigator in a prior life, we all die a little when 

 we loose a fellow aviator.  It is our mission not to bury our loss by 

 saying it can't happen to me, but to try to make the aircraft, 

 procedures, or training better to save not just ourselves, but others 

 who come after us so they don't have to experience our loss. 

  

 Just my thoughts.

  

 Bud Yerly

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grahamsingleton(at)btinte
Guest

Posted: Wed Oct 14, 2009 3:20 pm Post subject: Mod 73

Bud Yerly wrote:

 	  Quote: 	
		   Fred,

 Here is my two cents as an average builder:

 As an accident investigator in a prior life, we all die a little when 

 we loose a fellow aviator.  It is our mission not to bury our loss by 

 saying it can't happen to me, but to try to make the aircraft, 

 procedures, or training better to save not just ourselves, but others 

 who come after us so they don't have to experience our loss. 

 Bud Yerly

  

Bud
	


I couldn't agree more

Graham

fklein(at)orcasonline.com
Guest

Posted: Wed Oct 14, 2009 4:30 pm Post subject: Mod 73

On Oct 14, 2009, at 4:18 PM, Graham Singleton wrote:



 	  Quote: 	
		  > As an accident investigator in a prior life, we all die a little  

> when we loose a fellow aviator.  It is our mission not to bury our  

> loss by saying it can't happen to me, but to try to make the  

> aircraft, procedures, or training better to save not just  

> ourselves, but others who come after us so they don't have to  

> experience our loss. Bud Yerly

>

 Bud

 I couldn't agree more

 Graham


	


Graham...I too quite agree w/ Bud's sentiments.



In our common interest of making our aircraft better, would you  

venture an opinion on the tailplane "fix" shown in John Wigney's  

photos posted earlier today?



Thanks,



Fred

A194

ptag.dev(at)tiscali.co.uk
Guest

Posted: Thu Oct 15, 2009 12:24 am Post subject: Mod 73

Hi! Fred

You probably weren't asking me about my opinion of the photo's of the fix

which John Wigney published but here goes anyway.

I think it is an excellent fix with one note of caution which is that I

don't like shaving down the flange of the drive plate. I would have thought

it possible to make the lever bent in the right places to still do it's job

as per the concept, without weakening the drive plate.

Like it or not you now have my humble opinion!

Regards

Bob Harrison G-PTG



--

grahamsingleton(at)btinte
Guest

Posted: Thu Oct 15, 2009 1:44 am Post subject: Mod 73

Fred Klein wrote:

 	  Quote: 	
		   



Fred
	


imho John's solution is adding more engineering to fix a symptom. I 

would prefer removing the cause, which is relying on the adhesion of 

epoxy to stainless steel. Purely mechanical, no true bond. Better to 

make a glass tube properly laid up onto the foam core and the ribs, 

lined with a full length tube with lightening holes. Much more expensive 

in labour but hey, we can always pay ourselves a bit less that day 

The problem is the stainless inserts are not always circular and a bit 

of swarf from the drillings make them jamb. Trouble!

Graham

peterz(at)zutrasoft.com
Guest

Posted: Thu Oct 15, 2009 3:00 am Post subject: Mod 73

FWIW, In addition to fixing the original design problem as per the suggestiong below, I am planning on a simple stainless spring-clip on the tailplane which catches the drive-plate as a fail-safe backup.

  

 Cheers,

 Pete

 A239

 On Thu, Oct 15, 2009 at 5:43 AM, Graham Singleton <grahamsingleton(at)btinternet.com (grahamsingleton(at)btinternet.com)> wrote:

 [quote] --> Europa-List message posted by: Graham Singleton <grahamsingleton(at)btinternet.com (grahamsingleton(at)btinternet.com)>

 Fred Klein wrote:

  	  Quote: 	
		  --> Europa-List message posted by: Fred Klein <fklein(at)orcasonline.com (fklein(at)orcasonline.com)>

 

	


Fred

imho John's solution is adding more engineering to fix a symptom. I would prefer removing the cause, which is relying on the adhesion of epoxy to stainless steel. Purely mechanical, no true bond. Better to make a glass tube properly laid up onto the foam core and the ribs, lined with a full length tube with lightening holes. Much more expensive in labour but hey, we can always pay ourselves a bit less that day 

 The problem is the stainless inserts are not always circular and a bit of swarf from the drillings make them jamb. Trouble!

Graham   

 ist Un/Subscription,

 www.matronics.com/Navigator?Europa-List" target="_blank">http://www.matronics.com/Navigator?Europa-List

 ronics.com/" target="_blank">http://forums.matronics.com

 Matt Dralle, List Admin.

 =====



[b]

kheindl(at)msn.com
Guest

Posted: Thu Oct 15, 2009 3:24 am Post subject: Mod 73

Surely C the objective of mod 73 was to prevent the tailplanes from moving outboard. There is no guarantee that this 'plaster' stuck onto stainless is going to last the life of the aircraft.

 What is wrong with my simple fix of replacing the TP5 with a long TP5 reaching up to the TP6 C ensuring that the TP6 cannot ever move inboard.

 This also fixes another problem C namely the disbonding of the TP5s  C which has happened to me on both tailplanes.

 BTW C I have never noticed any tendency of the tailplanes migrating outboard. Whenever I remove the tailplanes at the end of my season C the pip pins are still as free and easy as when they went in.

 Karl

 	  Quote: 	
		   Date: Thu C 15 Oct 2009 10:43:46 +0100

 From: grahamsingleton(at)btinternet.com

 To: europa-list(at)matronics.com

 Subject: Re: Mod 73

 --> Europa-List message posted by: Graham Singleton <grahamsingleton(at)btinternet.com>

 Fred Klein wrote:

 > --> Europa-List message posted by: Fred Klein <fklein(at)orcasonline.com>

 >

 Fred

 imho John's solution is adding more engineering to fix a symptom. I 

 would prefer removing the cause C which is relying on the adhesion of 

 epoxy to stainless steel. Purely mechanical C no true bond. Better to 

 make a glass tube properly laid up onto the foam core and the ribs C 

 lined with a full length tube with lightening holes. Much more expensive 

 in labour but hey C we can always pay ourselves a bit less that day 

 The problem is the stainless inserts are not always circular and a bit 

 of swarf from the drillings make them jamb. Trouble!

&gt======================

&gt==================

[quote] 

 		 	   		     	  Quote: 	
		  [b]

craigb(at)onthenet.com.au
Guest

Posted: Thu Oct 15, 2009 3:54 am Post subject: Mod 73

" What is wrong with my simple fix of  replacing the TP5 with a long TP5 reaching up to the TP6, ensuring that the TP6  cannot ever move inboard.

This also fixes another problem, namely the  disbonding of the TP5s , which has happened to me on both tailplanes. " 

 

Karl " 



 That is exactly  what i did during the build. I sourced alloy tube with  the same ID as the  TP5/6 tubes, made it about 100mm longer

 than the  torque tube, so it runs from the inner plywood where the drive bushes are  out past the central rib in the tailplane. It did  require

 a slight  change in the build order, as i epoxied it into the foam before I created the  rib, this however would be hard to do on a completed

 tailplane.

  

 craig   



 



[quote] [b]

pjeffers(at)talktalk.net
Guest

Posted: Thu Oct 15, 2009 5:21 am Post subject: Mod 73

Karl,

    

   When taking the tailplanes on and off the friction produced by having 6 or 7 times the contact are between the torque tubes and the TP bushes would be enormous and add a significant weight penalty to an area with great lever arm IE CG considerations.

   Re the plaster stuck onto stainless. This is the significant improvement made by the mod in that disbondment is now prohibited, by introduction of a physical barrier to migration of the bush.  Previously it was only held in place by the adhesion of stainless to structure in one linear direction.

    

   Pete 

 

 

 --

fklein(at)orcasonline.com
Guest

Posted: Thu Oct 15, 2009 7:23 am Post subject: Mod 73

On Oct 15, 2009, at 1:15 AM, Robert C Harrison wrote:



 	  Quote: 	
		   You probably weren't asking me about my opinion of the photo's of  

 the fix

 which John Wigney published but here goes anyway.


	


Bob...au contraire...I welcome opinions from all sources...Fred



do not archive

budyerly(at)msn.com
Guest

Posted: Thu Oct 15, 2009 7:41 am Post subject: Mod 73

<?xml:namespace prefix="v" /><?xml:namespace prefix="o" /><![endif]-->  Karl,

 The problem is friction of the tight fit of the TPs.  The longer the  bearing, the more force to get it on and off.

 Making a tube of glass (using the method of wax paper or similar to keep  the glass from direct contact) where both edges of the TPs have a lip which not  only holds the bearing in shear, but in compression (via the lip) also.   This would be slightly less force required on installation and removal, and  as the tube passes into the stab, prevent a hard metal to metal impact on the  outer bearing possibly creating a shock failure...

  

 Of course I cringe in how some folks take their tail planes off and  on.  No bearing would stay put the way some are handled.  It is all in  balance and alignment as well as the oh so important patience.

  

 As you have found, properly built and maintained tailplanes can last  forever.  Congrats on a well built stab.

 You obviously did a fine job.

  

 Bud

 [quote]   ---

kheindl(at)msn.com
Guest

Posted: Thu Oct 15, 2009 8:24 am Post subject: Mod 73

Pete and Bud C

  

 I don't agree with the friction theory. My tailplanes slide on and off with ease. If anything C it is easier now C as there is no lignup problem with the two separate tubes. The torque tube is always lightly greased for that reason C but also to keep corrosion of the torque tube at bay.e

 I don't think that weight is an issue here. I use an alu tube and the difference between that and the shorter steel tube is really minimal. 

 Actually C an increase in tail weight is beneficial for many Europas C when you consider all the add-ons up front C like cs propeller C instrumentation C autopilot C cabin heat C you name it C compared to the original 80hp mono C on which the cg calculations were based.

  

 Karl

 

 

 



  

  To: europa-list(at)matronics.com

Subject: Re: Mod 73

Date: Thu C 15 Oct 2009 09:19:16 -0400

From: pjeffers(at)talktalk.net



 Karl C

  

 When taking the tailplanes on and off the friction produced by having 6 or 7 times the contact are between the torque tubes and the TP bushes would be enormous and add a significant weight penalty to an area with great lever arm IE CG considerations.

 Re the plaster stuck onto stainless. This is the significant improvement made by the mod in that disbondment is now prohibited C by introduction of a physical barrier to migration of the bush.  Previously it was only held in place by the adhesion of stainless to structure in one linear direction.

  

 Pete 

--

budyerly(at)msn.com
Guest

Posted: Thu Oct 15, 2009 9:23 am Post subject: Mod 73

<?xml:namespace prefix="v" /><?xml:namespace prefix="o" /><![endif]-->  I see, you use aluminum tube.  The aluminum tube is probably 1/8  larger (outside) and at .049 thick gives you about 3-4 thousandths  clearance for a better slip fit.  Hence our concern with friction, thinking  you were using the stainless tube.

  

 Bud

 [quote]   ---

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