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Downed EAA Plane

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jay(at)horriblehyde.com
Guest

Posted: Tue Mar 30, 2010 4:05 am Post subject: Downed EAA Plane

An interesting thing about jamb-nuts; if we are thinking of the same thing

here.  We call them 'half-nuts'; usually people place the full sized nut

under the half or jamb nut- I used to as well.  However, the correct way is

to put the thin nut first - see 

http://www.boltscience.com/pages/twonuts.htm



Jay

--

longg(at)pjm.com
Guest

Posted: Tue Mar 30, 2010 6:00 am Post subject: Downed EAA Plane

Regardless of your ego, it's always good to read 43.13 part 1 & 2 when

building an airplane. It's written at a 9th grade level so little things

like that should not get by. They make a big deal on exposed threads for

studs, bolts etc. How many of you know the formula for how deep a stud

needs to be screwed in? It's so simple, if you can't see 2 threads, get

a longer bolt.



In areas where I can't frequently inspect potential loose nuts, I always

use Loctite and if I'm feeling particularly nervous I give the thread

and nut a thin coat of epoxy. There's lots of other neat stuff in the

43.13 like max number of washers, 3 and never use a jam nut more than

once - toss it.



It's your ass in the plane, so do it right.



Glenn



--

jon(at)finleyweb.net
Guest

Posted: Tue Mar 30, 2010 6:25 am Post subject: Downed EAA Plane

Glenn,

  

 Please explain the purpose of your "ego" comment.

  

 Jon

DO NOT ARCHIVE

 

--

longg(at)pjm.com
Guest

Posted: Tue Mar 30, 2010 6:54 am Post subject: Downed EAA Plane

Jon,



Ego may imply I know better than the book, or jeez, I'd have to walk all the way back to the shop for a longer bolt - I'll put it in on next time. Just like in flying, the macho attitude (John Kennedy) will get you into as much trouble as the resignation attitude. Build it and fly it by the book, then we have the right to complain to someone else.



Glenn



--

rampil

Joined: 04 May 2007
Posts: 870

Posted: Tue Mar 30, 2010 9:22 am Post subject: Re: Downed EAA Plane

Glenn,



Before you insult old ghosts, maybe you should read the 14 page

(if I recall correctly) NTSB report on John-Johns accident.

His flying endeavors were marked, in my opinion, by always trying

hard to do the right thing.  I don't think he was cavalier or ego-driven

at all, just unlucky. He may not have had the aptitude for instrument

flight, but he tried hard, and attended the best IFR flight school in the

country at the time



http://ntsb.gov/ntsb/brief2.asp?ev_id=20001212X19354&ntsbno=NYC99MA178&akey=1



It was his sister-in-law's fault!

I am not now, nor have I ever been a fan of the Kennedy dynasty, tho

I did admire Jack and Bobby!

_________________
Ira N224XS

longg(at)pjm.com
Guest

Posted: Tue Mar 30, 2010 10:40 am Post subject: Downed EAA Plane

You're joking right? His head was bigger than the airplane. That was his

MO. He was all about driving that thing out into the dark on his own. As

you may remember he turned down the offer of the CFI going along with

him.



What he did was let one small mistake build up into a giant one -

especially with family on board. Get-there-itis got him. If he had flown

by the book and did what he learned at the best IFR schools at first

entry into IMC or simply darkness he would have turned right around and

gone back inland.



He is now the butt of every CFI example of what happens to a pilot when

orientation is lost. Sure one can be unlucky, but I don't buy that in

his case.



I suppose we'll never really know.



Glenn



--

simon(at)synchdes.com
Guest

Posted: Tue Mar 30, 2010 11:36 am Post subject: Downed EAA Plane

Glen and Ira,

 

 What I've always wondered about with the fatal John-John flight was "why didn't he turn on the autopilot and let it fly him in IMC to his destination?"  Didn't his Saratoga have autopilot?  He must have been distracted by the two passengers on board, who had a lot to talk about.  I've flown into dark areas before I had my instrument rating, and it scared the holy hel out of me-enough to fly back into VMC.

 

 I've never been a fan of the Kennedy dynasty either.  I have a t-shirt with a picture of Ted Kennedy and O.J. Simpson on it.  Below it, it says "Vodka and OJ."

 

 Simon Ramirez

 Do Not Archive

 

 

 On 3/30/2010 2:34 PM, longg(at)pjm.com (longg(at)pjm.com) wrote: [quote]   [quote]--> AeroElectric-List message posted by: <longg(at)pjm.com> (longg(at)pjm.com)  You're joking right? His head was bigger than the airplane. That was his MO. He was all about driving that thing out into the dark on his own. As you may remember he turned down the offer of the CFI going along with him.  What he did was let one small mistake build up into a giant one - especially with family on board. Get-there-itis got him. If he had flown by the book and did what he learned at the best IFR schools at first entry into IMC or simply darkness he would have turned right around and gone back inland.  He is now the butt of every CFI example of what happens to a pilot when orientation is lost. Sure one can be unlucky, but I don't buy that in his case.  I suppose we'll never really know.  Glenn  --

MauleDriver(at)nc.rr.com
Guest

Posted: Tue Mar 30, 2010 11:36 am Post subject: Downed EAA Plane

You must be joking.  I've read the report and analysis of the report 

several times.  Lot's to learn there but I never got enough info to know 

that his "head was bigger than the airplanes" or "that was his MO".



He screwed up and I've caught myself  with a dismissive smile while 

describing the incident to others.  I'll try harder to check myself in 

the future.



There but for the grace of whoever, goes I.  Thinking I'll never be 

subject to a simliar set of circumstances takes a pretty big head.



I agree, we'll never know,

Bill Watson



longg(at)pjm.com wrote:

[quote] 



 You're joking right? His head was bigger than the airplane. That was his

 MO. He was all about driving that thing out into the dark on his own. As

 you may remember he turned down the offer of the CFI going along with

 him.



 What he did was let one small mistake build up into a giant one -

 especially with family on board. Get-there-itis got him. If he had flown

 by the book and did what he learned at the best IFR schools at first

 entry into IMC or simply darkness he would have turned right around and

 gone back inland.



 He is now the butt of every CFI example of what happens to a pilot when

 orientation is lost. Sure one can be unlucky, but I don't buy that in

 his case.



 I suppose we'll never really know.



 Glenn



 --

ceengland(at)bellsouth.ne
Guest

Posted: Tue Mar 30, 2010 12:23 pm Post subject: Downed EAA Plane

I'm no engineer, & don't even plan to stay in *any* motel at S&F, but it 

will take more than a web site to convince me those instructions are 

correct. If I'm following their instructions correctly, the preload on 

the bolt will only be 25-50% of design (could easily wind up being even 

less) & the only spot with 100% of the preload will be the threads 

between the nuts.



The deal on that bridge will need to be a lot better to get my 

attention. 



Charlie



On 3/30/2010 7:01 AM, Jay Hyde wrote:

[quote] 



 An interesting thing about jamb-nuts; if we are thinking of the same thing

 here.  We call them 'half-nuts'; usually people place the full sized nut

 under the half or jamb nut- I used to as well.  However, the correct way is

 to put the thin nut first - see

 http://www.boltscience.com/pages/twonuts.htm



 Jay

 --

nuckolls.bob(at)aeroelect
Guest

Posted: Tue Mar 30, 2010 1:16 pm Post subject: Downed EAA Plane

At 03:16 PM 3/30/2010, you wrote:


<ceengland(at)bellsouth.net>



I'm no engineer, & don't even plan to stay in *any* motel at S&F, but 

it will take more than a web site to convince me those instructions 

are correct. If I'm following their instructions correctly, the 

preload on the bolt will only be 25-50% of design (could easily wind 

up being even less) & the only spot with 100% of the preload will be 

the threads between the nuts.



    I read the article with interest and a sense

    of mystery. Slicing and dicing distribution of

    total loads between two nuts, one of which

    ISN'T INTENDED TO BE STRUCTURAL gives one pause

    to ponder.



    Consider the host of anti-loosening technologies

    including toothed lock washers, winged lock washers

    keyed to a shaft and bent up to capture flats of the

    installed nut, distorted diameters designed to

    multiply friction between nut and bolt, locking

    goos and gunks, plastic or fiber inserts on the

    nuts or even the bolts, cotter keys through drilled

    or castellated nuts, and finally the lowly hunk

    of safety wire.



    The laws of physics including a study of basic machines,

    coefficients of friction and sliding forces tending

    to move down an inclined plane will show that no

    threaded fastener torqued to design values will rotate

    on its mate unless for some reason tension on the

    bolt is relaxed or strong but transient forces

    vibrations) tend to overcome the breaking coefficient

    of friction in the threads is overcome.



    None of the cited prophylactics against inadvertent

    loosening of a threaded couple take any part

    whatsoever in the structural task assigned to

    the threaded fasteners.  Hence I find it curious

    that one takes the time to put up such an explanation

    about some seemingly critical function of jam nuts

    on the structural integrity of the joint.



    I've never seen a jamb nut installed anywhere

    but on top of the nut it is intended to restrain.

    Further, I'll bet that installation torque values

    are a tiny fraction of that assigned to the

    structural nut. This is because the friction forces normal

    to the structural nut are being opposed by addition

    of the jam nut. Depending on how much slop there

    is in the threads, total release of tension on the

    could result in total loss of "jamb" between the

    two nuts.



    As a class of anti-rotation device, I think the

    jamb nut is the least capable of them all. I think

    I'd consider all the alternatives before stacking

    a jamb nut on top of a joint with any responsibility

    for keeping the airplane and its accessories whole.



    Bob . . .

endspeed(at)yahoo.com
Guest

Posted: Tue Mar 30, 2010 4:36 pm Post subject: Downed EAA Plane

Boy oh boy, 



  You know, aside from the whole celebrity mirage our country seems to have either fallen in love with, or to resent, you can't lose sight of the fact these are just people.  So now we have jousted with the ghosts of celebrity in John Jr's instance and one projected his belief's about him on to him, probably because of jealousy, plain and simple.  I had a best friend in college who actually went on to have business dealings personally with JFK, Jr.  He told me when I asked that JFK, Jr. was a really nice person as was Caroline.  He told me their mom did a great job raising them after their dad was murdered.  So, put your People Magazine away and realize a pilot, who was a great guy from my insider info, succumbed to the same errors many pilots have and learn from the facts.  Enough said.



Bob Sultzbach





Sent from my iPhone



On Mar 31, 2010, at 1:22, "rampil" <ira.rampil(at)gmail.com> wrote:






Glenn,



Before you insult old ghosts, maybe you should read the 14 page

(if I recall correctly) NTSB report on John-Johns accident.

His flying endeavors were marked, in my opinion, by always trying

hard to do the right thing.  I don't think he was cavalier or ego-driven

at all, just unlucky. He may not have had the aptitude for instrument

flight, but he tried hard, and attended the best IFR flight school in the

country at the time



http://ntsb.gov/ntsb/brief2.asp?ev_id 001212X19354&ntsbno=NYC99MA178&akey=1



It was his sister-in-law's fault!

I am not now, nor have I ever been a fan of the Kennedy dynasty, tho

I did admire Jack and Bobby!



--------

Ira N224XS





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=292377#292377

pwmac(at)sisna.com
Guest

Posted: Tue Mar 30, 2010 4:37 pm Post subject: Downed EAA Plane

Bob,

 You are correct. The application of a jam nut for locking is only applicable when one cannot wrench on the other end of the bolt. And never in a critical application. An example that comes to mind is a big relay where the bolt is molded into the plastic.



 Its interesting that some tend to focus on how many threads are showing instead of "is the thing torqued with a locking feature nut". Mechanical locking nuts are favored (some call Pinch nuts). The castellated nut does not have my favor since the holes seldom meet my needs. Safe enough if torqued properly. The nylon nuts (called elastic stop nuts) are applicable for non critical places with no heat. Otherwise loctite in cool environs is also good and comes in several degrees of anti rotation sticky ness.

 Paul

 ==========

 At 02:15 PM 3/30/2010, Robert L. Nuckolls, III"  wrote:

 [quote]As a class of anti-rotation device, I think the

    jamb nut is the least capable of them all. I think

    I'd consider all the alternatives before stacking

    a jamb nut on top of a joint with any responsibility

    for keeping the airplane and its accessories whole.



    Bob .[b]

MauleDriver(at)nc.rr.com
Guest

Posted: Tue Mar 30, 2010 5:54 pm Post subject: Downed EAA Plane

I like the phrase, "aside from the whole celebrity mirage...".  Nice.



Bill

 

Robert Sultzbach wrote:

 	  Quote: 	
		   



 Boy oh boy, 



   You know, aside from the whole celebrity mirage our country seems to have either fallen in love with, or to resent, you can't lose sight of the fact these are just people.  So now we have jousted with the ghosts of celebrity in John Jr's instance and one projected his belief's about him on to him, probably because of jealousy, plain and simple.  I had a best friend in college who actually went on to have business dealings personally with JFK, Jr.  He told me when I asked that JFK, Jr. was a really nice person as was Caroline.  He told me their mom did a great job raising them after their dad was murdered.  So, put your People Magazine away and realize a pilot, who was a great guy from my insider info, succumbed to the same errors many pilots have and learn from the facts.  Enough said.



 Bob Sultzbach



   

do not archive

user9253

Joined: 28 Mar 2008
Posts: 1944
Location: Riley TWP Michigan

Posted: Wed Mar 31, 2010 4:22 am Post subject: Re: Downed EAA Plane

 	  Quote: 	
		  The laws of physics including a study of basic machines, coefficients of friction and sliding forces tending to move down an inclined plane will show that no threaded fastener torqued to design values will rotate on its mate unless for some reason tension on the bolt is relaxed or strong but transient forces vibrations) tend to overcome the breaking coefficient of friction in the threads is overcome. 	


I agree.  The only advantage of using a jam nut that I see is that if the load on the bolt is relaxed, the two nuts will still be tight against each other.  On non-aviation projects, I have used two nuts with a lock washer between them and never had them come loose.

Joe

_________________
Joe Gores

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