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Hole Enlongation vs. Landing Gear Type

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TELEDYNMCS(at)aol.com
Guest

Posted: Mon Jun 25, 2007 5:18 am Post subject: Hole Enlongation vs. Landing Gear Type

Greetings team,

  

 As I read through the various theories of why the pin holes elongate I'm  left with a question that nobody seems to be asking (or maybe somebody did ask  and I missed it).

 

This is a little out of my area of expertise, but it seems rational to  me that either a mono or a conventional gear Europa, i.e., one with a tailwheel,  would transfer significantly more stress loads to the components in the  rear of the aircraft, thus leading to more wear on everything back there. By  contrast, the trigear would dampen those stress loads by virtue of the main gear  being a considerable distance from the parts in question, thus damping any  forces transferred to the tail area. Stresses transferred by a trigear would  further be damped by the spring action of the main gear legs and the tires  (tyres).

  

 Has anyone ever correlated pin wear to landing gear type? Are there more  mono's and conventional gear Europa's showing pin wear and or hole  elongation than trigears?

  

 In my case, N245E, a trigear, now has a bit over 100 hours TT. About  90% of the take offs and landings thus far have been made from my grass  strip and my pip pins are still tight as a tick. I have observed no  increased play in the tailplanes and only a slight amount of play in the  trim tabs and that hasn't changed since day one. I've also looked closely at all  the hardware in the tail and I cannot detect any wear on any components  whatsoever. I know this is anecdotal at best, but it seams reasonable for those  in the know to correlate pin wear to landing gear type as they chase down  the root cause of the wear that caused the tailplane  flutter.

  

 Regards,

  

 John Lawton

 Whitwell, TN (TN89)

 N245E - Flying

  



See what's free at AOL.com. 

  [quote][b]

Mark Burton

Joined: 10 Jan 2006
Posts: 74

Posted: Mon Jun 25, 2007 5:43 am Post subject: Re: Hole Enlongation vs. Landing Gear Type

 	  Quote: 	
		  the wear that caused the tailplane flutter 	




At this time, we don't know that any wear (if it was actually present) did cause the flutter. The AAIB/PFA may decide that the evidence shows that it did but they haven't, to my knowledge, announced that yet.



Please don't missunderstand me, I am all for improving the integrity of the Europa tailplane system but let's base the discussion on known facts rather than guesses.



Mark

RobNeils(at)qwest.net
Guest

Posted: Mon Jun 25, 2007 7:21 am Post subject: Hole Enlongation vs. Landing Gear Type

N128HW, a tri-gear motorglider, is operated out of a grass strip (WN92,  Spokane, Washington).  The tailplane is tight across all parameters after  150 hours of engine time.

 [quote]   ---

rampil

Joined: 04 May 2007
Posts: 870

Posted: Mon Jun 25, 2007 7:42 am Post subject: Re: Hole Enlongation vs. Landing Gear Type

To take Mark's point a bit further, we do not even know at this point

that flutter was indeed involved in this mishap.  All that is publically known

is that a worst case presumption of flutter was stated as a rationale to

ground the (UK) fleet.



I'd personally like to know if the physical evidence is strongly suggestive,

or simply possible of a link to flutter.  Were there close by witnesses, were

the tailplanes 500 feet behind the rest of the airframe? Is a metallurgical

analysis of the torque tube being done?



The mention of flutter has brought a whole lot of comment, including 

many suggestions to repair components which are not yet know to be

responsible.



It would certainly be nice if Andy, or someone from E04 could elucidate

the situation instead of having all of us wait in the dark for 12 months.



Ira

_________________
Ira N224XS

Brian Davies

Joined: 10 Jan 2006
Posts: 124
Location: uk

Posted: Mon Jun 25, 2007 9:43 am Post subject: Hole Enlongation vs. Landing Gear Type

Ira,



For clarification, the UK Europa fleet is not grounded.  Only those aircraft

that have failed the PFA Flight Safety Bulletin are grounded until

rectification action is taken.  We have indications that the AAIB will be

issueing a preliminary report within the next week.



We all want a lasting and efficient solution to whatever is judged to be the

fix for a yet unspecified problem.  Regrettably, this always results in a

delay whilst investigations are carried out and modifications (if necessary)

are designed.



Brian Davies 



--

rampil

Joined: 04 May 2007
Posts: 870

Posted: Mon Jun 25, 2007 10:35 am Post subject: Re: Hole Enlongation vs. Landing Gear Type

Hi Brian,



Thank you for the clarification.

It had been my understanding that all UK Europas were grounded until

offical inspection and that the majority of those aircraft inspected actually

failed inspection from the comments posted here.



Is there anything that can be made public about the nature of the evidence

for stabilator oscillation to destructive failure?

Regards,



Ira

_________________
Ira N224XS

Brian Davies

Joined: 10 Jan 2006
Posts: 124
Location: uk

Posted: Mon Jun 25, 2007 1:33 pm Post subject: Hole Enlongation vs. Landing Gear Type

Nothing concrete yet, Ira.



We will just have to wait a few more days to hear what the AAIB have found.



Brian 



--

grahamsingleton(at)btinte
Guest

Posted: Mon Jun 25, 2007 2:58 pm Post subject: Hole Enlongation vs. Landing Gear Type

John

you are probably right, or lucky, or both.

Graham



TELEDYNMCS(at)aol.com wrote:

  it seems rational to  me that either a mono or a conventional gear 

Europa, i.e., one with a

 	  Quote: 	
		   tailwheel, would transfer significantly more stress loads to the 

 components in the rear of the aircraft, thus leading to more wear on 

 everything back there. By contrast, the trigear would dampen those 

 stress loads by virtue of the main gear being a considerable distance 

 from the parts in question, thus damping any forces transferred to the 

 tail area. Stresses transferred by a trigear would further be damped by 

 the spring action of the main gear legs and the tires (tyres).

  

 John Lawton

 Whitwell, TN (TN89)

 N245E - Flying

TELEDYNMCS(at)aol.com
Guest

Posted: Tue Jun 26, 2007 6:32 am Post subject: Hole Enlongation vs. Landing Gear Type

In a message dated 6/26/2007 2:59:32 AM Eastern Daylight Time,  europa-list(at)matronics.com writes:

  	  Quote: 	
		  At this    time, we don't know that any wear (if it was actually present) did    cause

the flutter. The AAIB/PFA may decide that the evidence shows that it    did but

they haven't, to my knowledge, announced that yet.



Please    don't missunderstand me, I am all for improving the integrity of the    Europa

tailplane system but let's base the discussion on known facts rather    than

guesses. 	
  

 Mark, 



 I'm not guessing about anything here. The purpose of the question I  posed was entirely aimed at obtaining facts about whether or not  there anyone had noticed a correlation between torque tube wear and  landing gear type, not to guess whether or not tailplane flutter caused the  accident. It's the PFA that is all hot and bothered about  associating pitch system wear and tailplane flutter, not me. It's the  PFA that has issued documents that infer a link to sloppiness in the pitch  system to tailplane flutter based on a single, isolated incident, and the  notion (or guess if you will) that tailplane flutter is what caused the crash,  not me. It's the PFA that seems to be the one that is doing  the guessing here, not me. All I did was read the documents the  PFA released regarding this incident and, based on their  commentary, asked a legitimate question about whether anyone had  noticed a correlation between landing gear type and torque tube  wear. Although it seems like an obvious question to me, judging  by the responses thus far, apparently no one has bothered to look for a  correlation. 

 

If Europa 04 keeps records on who they've sold Mod 62 kits to and what  kind of landing gear the aircraft uses, it would be easy to see if the wear on  the torque tube(s) is more prevalent in mono's, trigears or neither. Since  the PFA seems to be suggesting (guessing) that wear in the pitch  system possibly lead to tailplane flutter which resulted in the recent crash in  the UK, it stands to reason that the PFA would want to isolate those  aircraft where the wear is more likely to occur, if indeed wear is more  prevalent in one type of landing gear as opposed to another and if sloppiness in  the pitch system lead to tailplane flutter and if that flutter caused the crash.  If indeed this is the case, the focus of any corrective action should be  directed where it is most needed. What the PFA has done so far is the  scatter-gun approach.

 



Regards,

  

 John Lawton

 Whitwell, TN (TN89)

N245E - Flying

  

  

  

  

  

  

 

  



See what's free at AOL.com. 

  [quote][b]

carl(at)flyers.freeserve.
Guest

Posted: Tue Jun 26, 2007 7:54 am Post subject: Hole Enlongation vs. Landing Gear Type

Hey guys, were on the same side - arent we?

  

 The PFA are on our side too in case anyone thought otherwise!  I agree  they are doing a lot of guessing but at least its educated as opposed to the  speculation that has been going on in this forum (and I include myself in that  category). 

  

 Its understandable that we all want answers but taking exception at what  someone has said is pointless and unecessary.

  

 It would be better if we all shut up and waited till the AIIB publishes its  findings but that aint going to happen - is it?

 [quote]   ---

willie.harrison(at)tinyon
Guest

Posted: Tue Jun 26, 2007 8:49 am Post subject: Hole Enlongation vs. Landing Gear Type

John



It is a fair question, but we'd need to be careful in interpreting the answer - Monos tend to be older and more home-crafted than tris so you'd have to disentangle those factors from any possible direct link between slop and undercarriage configuration.



Incidentally, a senior bod at the PFA told one of our colleagues earlier this week that "We may never know the full story".  We may be stuck therefore with having to adopt the scatter gun approach to ensuring the integrity of our aircraft.



Willie Harrison

G-BZNY (passed all its FSB 006 checks today. Popham here we come...)



On 26 Jun 2007, at 15:31, TELEDYNMCS(at)aol.com (TELEDYNMCS(at)aol.com) wrote:

[quote]  In a message dated 6/26/2007 2:59:32 AM Eastern Daylight Time, europa-list(at)matronics.com (europa-list(at)matronics.com) writes:

  	  Quote: 	
		  At this   time, we don't know that any wear (if it was actually present) did   cause

the flutter. The AAIB/PFA may decide that the evidence shows that it   did but

they haven't, to my knowledge, announced that yet.



Please   don't missunderstand me, I am all for improving the integrity of the   Europa

tailplane system but let's base the discussion on known facts rather   than

guesses. 	
  

 Mark, 



 I'm not guessing about anything here. The purpose of the question I posed was entirely aimed at obtaining facts about whether or not there anyone had noticed a correlation between torque tube wear and landing gear type, not to guess whether or not tailplane flutter caused the accident. It's the PFA that is all hot and bothered about associating pitch system wear and tailplane flutter, not me. It's the PFA that has issued documents that infer a link to sloppiness in the pitch system to tailplane flutter based on a single, isolated incident, and the notion (or guess if you will) that tailplane flutter is what caused the crash, not me. It's the PFA that seems to be the one that is doing the guessing here, not me. All I did was read the documents the PFA released regarding this incident and, based on their commentary, asked a legitimate question about whether anyone had noticed a correlation between landing gear type and torque tube wear. Although it seems like an obvious question to me, judging by the responses thus far, apparently no one has bothered to look for a correlation. 

 

If Europa 04 keeps records on who they've sold Mod 62 kits to and what kind of landing gear the aircraft uses, it would be easy to see if the wear on the torque tube(s) is more prevalent in mono's, trigears or neither. Since the PFA seems to be suggesting (guessing) that wear in the pitch system possibly lead to tailplane flutter which resulted in the recent crash in the UK, it stands to reason that the PFA would want to isolate those aircraft where the wear is more likely to occur, if indeed wear is more prevalent in one type of landing gear as opposed to another and if sloppiness in the pitch system lead to tailplane flutter and if that flutter caused the crash. If indeed this is the case, the focus of any corrective action should be directed where it is most needed. What the PFA has done so far is the scatter-gun approach.

 



Regards,

  

 John Lawton

 Whitwell, TN (TN89)

N245E - Flying

  

  

 [b]

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