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Safe Wire Types

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jhausch

Joined: 14 Jan 2008
Posts: 35

Posted: Sun Aug 05, 2012 12:28 pm Post subject: Safe Wire Types

Ran across this link.  Did some searching here to see if posted previously, but that does not seem to be the case.



Anyone's thoughts on this?

http://www.vision.net.au/~apaterson/aviation/wire_types.htm

medorrisjr(at)hotmail.com
Guest

Posted: Sun Aug 05, 2012 2:38 pm Post subject: Safe Wire Types

 

 If you're building a new airplane, use TKT Boeing or maybe TKT Airbus.  If you have to fly in something older, or something that doesn't have these types of wire, and something happens, blame your aviation safety advisor if you lose people.

  

 And I'm thinking of buying a 1960 Bonanza Debonair??????????

  

 Best Regards to All,

  

 



 

  

 	  Quote: 	
		   Subject: Safe Wire Types

 From: jimhausch(at)gmail.com

 Date: Sun, 5 Aug 2012 13:28:56 -0700

 To: aeroelectric-list(at)matronics.com

 

 --> AeroElectric-List message posted by: "jhausch" <jimhausch(at)gmail.com>

 

 Ran across this link. Did some searching here to see if posted previously, but that does not seem to be the case.

 

 Anyone's thoughts on this?

 http://www.vision.net.au/~apaterson/aviation/wire_types.htm

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=380111#380111

 

 

 

 

 

 

==============

 

 

 


	


 		 	   		  

  [quote][b]

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Aug 05, 2012 6:37 pm Post subject: Safe Wire Types

At 03:28 PM 8/5/2012, you wrote:

 	  Quote: 	
		  



Ran across this link.  Did some searching here to see if posted 

previously, but that does not seem to be the case.



Anyone's thoughts on this?

http://www.vision.net.au/~apaterson/aviation/wire_types.htm


	


   This tempest has been bubbling at various

   vapor-generation rates for decades . . .



   I'll begin by noting that there's no such

   thing as a 'safe' airplane . . . nor any

   other machine which operates in close proximity

   to people and other living creatures. Each

   one is simply a tool that offers certain risks

   associated with its construction and use.

   Every one of them, used or maintained carelessly

   will eat more than your lunch . . .



   There's little about the construction and

   operation of a OBAM aircraft to compare with an

   Air Transport category aircraft. The operation,

   maintenance, system complexities, and exposure

   to people-induced mishap have very little

   if anything in common.



   Mr. Paterson's heart is in the right place

   and he's privy to many facts surrounding the

   history of ATC aircraft. Yes, there have been

   a goodly number of incidents that had origins

   with electrically induced fires.



   How do these relate to your RV7 or even Lancair

   IVP?  Air Transport category flight cycles in US

   number in tens of thousands per day with about 1.8

   millions of souls arriving comfortably at their

   intended destination. The world wide figures

   would probably more than double that.



   What are the numbers of incidents of in-flight

   fire induced by electrical systems where

   the fire might have been avoided had the

   INSULATION been something different?



   There are many electrical systems issues

   that arise from damage by shipping containers

   in the hold, accumulation of lint from carpets

   and clothes in inaccessible places, drips from

   coffee makers in the galley and potty plumbing.

   Accumulation of hydraulic fluids, ingress of

   rainwater, splash from wheel wells, etc. etc.



   Those airplanes are operated to maximize revenue

   generating hours per day while our airplanes

   spend the overwhelming majority of their time

   parked. The ATC aircraft will experience more

   flight hours in a few months than your airplane

   will over it's lifetime . . . and be exposed to

   a thousand times more situations with a

   potential for mishap.



   Root cause of the majority of accidents

   in small aircraft do not originate with the

   electrical system at all . . . much less with

   the kind of insulation on the wires.



   There are thousands of airplanes flying with

   cotton covered rubber insulation popular in

   1940, tens of thousands flying with nylon over

   PVC used for a couple decades worth of Cessna/Piper/

   Beech production. Yet these less-than-exotic

   insulations go unnoticed for their alleged

   hazard . . . because they are very low risk.



   I've worked some issues on Hawkers originally

   certified with some exotic insulations that

   would arc-track and experienced some electrical

   events that did not precipitate a serious

   accident. I'm aware of no incidents involving

   electrical systems where Tefzel or pre-Tefzel

   insulation was a factor. In other words, I

   don't see the incident rates going down because

   the insulation on the wire is Part 25 qualified.



   Yes, people who are paid to worry are very

   good at their jobs. Some folks worry as a hobby

   or even out of a sense of civic duty. But none

   of these folks seem to put their work product

   into perspective for how it defines RISK.



   Even though there are thousands of airplanes

   flying with allegedly the worst possible

   insulation on their wires, what is the probability

   of any one planeload of folks is going to

   experience a bad day in the breaker box?



   There are conditions and forces in the overall

   flight system that contribute much greater

   factors to the grand equation that defines

   risk for failure to arrive comfortably at your

   intended destination. Further, the risk factors

   for leaking potty pipes and inattentive baggage

   handlers don't even figure into the grand

   equation for an RV.



   I cannot argue qualitatively with the assertions

   derived from a study of Mr. Patterson's data.

   I can refer to the performance history in

   things like King Airs and Beechjets . . . and

   my acquaintances who investigate accidents

   involving those kinds of aircraft.



   I suggest that probability of insulation failure

   of a Tefzel wire (or even PVC) is WAAaaayyyy out

   on some small branch of the system reliability

   matrix for your airplane. So far out that

   it's not worthy of investment for either capital

   or emotional resources.



   When I climb aboard a CJ and get a look at

   the cockpit crew who looks like they barely

   have to shave every day . . . or listen to the thumps

   and crashes coming from the baggage compartment,

   concerns for insulation on the ship's wiring do

   not even enter my mind.

   Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Aug 05, 2012 6:39 pm Post subject: Safe Wire Types

At 05:37 PM 8/5/2012, you wrote:



If you're building a new airplane, use TKT Boeing or maybe TKT 

Airbus.  If you have to fly in something older, or something that 

doesn't have these types of wire, and something happens, blame your 

aviation safety advisor if you lose people.



   Hmmm . . . where does one purchase this wire?



And I'm thinking of buying a 1960 Bonanza Debonair??????????



   How about it ol' Bob. Would you recommend the wire

   bundles be stripped out and replaced?

   Bob . . .

bob.verwey(at)gmail.com
Guest

Posted: Mon Aug 06, 2012 12:43 am Post subject: Safe Wire Types

Not Bob III, but if you want to replace the wiring in a Bonanza be prepared to strip the whole interior out. As a former A&P/IA, and current Bonanza owner, the only issue with the wiring in my opinion,  might be some of the circuit breakers, switches and limit switches.  On the Beech forum over the past ten years I don't recall seeing to many wiring issues that present a danger. The system might be regarded as old school, but it works!

Bob Verwey

 IO 470 A35 Bonanza  ZU-DLW



On 6 August 2012 04:39, Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:

 [quote]--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)>

  

 At 05:37 PM 8/5/2012, you wrote:

 

 If you're building a new airplane, use TKT Boeing or maybe TKT Airbus.  If you have to fly in something older, or something that doesn't have these types of wire, and something happens, blame your aviation safety advisor if you lose people.

  

   Hmmm . . . where does one purchase this wire?

 

 And I'm thinking of buying a 1960 Bonanza Debonair??????????

 

   How about it ol' Bob. Would you recommend the wire

   bundles be stripped out and replaced?

 

 

   Bob . . . 

 

 ====================================

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

 ====================================

 http://forums.matronics.com

 ====================================

 le, List Admin.

 ="_blank">http://www.matronics.com/contribution

 ====================================

 

 

 

 [b]

BobsV35B(at)aol.com
Guest

Posted: Mon Aug 06, 2012 3:16 am Post subject: Safe Wire Types

Good Morning Bob, Bob and All,

  

 I would not replace the wiring unless it showed evidence of unintended  motion., but would carefully check all of the grounds and check for voltage drop  across any suspect CBs and switches.

  

 Happy Skies,

  

 Old Bob

  

 PS Good to be able to meet you in RFD. Wish we could have talked a bit  more.

  

  In a message dated 8/6/2012 3:44:31 A.M. Central Daylight Time,  bob.verwey(at)gmail.com writes:

  	  Quote: 	
		  And I'm    thinking of buying a 1960 Bonanza Debonair??????????



  How about    it ol' Bob. Would you recommend the wire

  bundles be stripped out and    replaced?

  Bob . . .  

	


 [quote][b]

racerjerry

Joined: 15 Dec 2009
Posts: 202
Location: Deer Park, NY

Posted: Mon Aug 06, 2012 4:40 am Post subject: Re: Safe Wire Types

I cannot argue with anything that has been said here; however, the real problem lies at the ends of the wire.   



If you hook up your new Taiwan audio gadget with 20 feet of 24 AWG and connect it to a â€œconvenientâ€ 30 amp circuit breaker, you could find yourself in a would of hurt if the device decides to short out.  The breaker will never trip and the wire will become a smoke generator.  Ask me how I know.



Common hook-up wire purchased at your local electronics or auto parts store that has PVC insulation will get things over with quicker.  



Fortunately, my experience was in a service truck and not in a confined RV cockpit at altitude.  By the time I could get the truck stopped at the side of the road, I was totally helpless and on the ground choking.

_________________
Jerry King

nuckolls.bob(at)aeroelect
Guest

Posted: Mon Aug 06, 2012 4:41 am Post subject: Safe Wire Types

At 09:36 PM 8/5/2012, you wrote:

 --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>



 At 03:28 PM 8/5/2012, you wrote:

 --> AeroElectric-List message posted by: "jhausch" <jimhausch(at)gmail.com>



 Ran across this link.  Did some searching here to see if posted previously, but that does not seem to be the case.



 Anyone's thoughts on this?

  http://www.vision.net.au/~apaterson/aviation/wire_types.htm



 



   This tempest has been bubbling at various

   vapor-generation rates for decades . . .



   <SNIP>



   I've worked some issues on Hawkers originally

   certified with some exotic insulations that

   would arc-track and experienced some electrical

   events that did not precipitate a serious

   accident. I'm aware of no incidents involving

   electrical systems where Tefzel or pre-Tefzel

   insulation was a factor. In other words, I

   don't see the incident rates going down because

   the insulation on the wire is Part 25 qualified.



 

   I dug around in the archives and found some

   of my data and reports generated therefrom for

   the Hawker incidents cited.



 [img]cid:.0[/img]



 [img]cid:.1[/img]



 

   Note that damage to these bundles ORIGINATED with

   a single, small fault to ground. A contaminated

   crack or more probably, rubbed through by motion

   against the airframe. Note that this insulation

   is a tape WRAPPED around the wires and fused

   . . . not extruded as a contiguous amorphous

   sheath.



   Further, while these materials passed some form

   of qualification testing at the time the airplane

   was being designed, there was no investigation

   as to behaviors under excitation for temperatures

   produced by an electric arc that would trigger

   a previously unconsidered form of propagation

   for combustion . . . now called "arc tracking."



   A fault in a single wire propagated catastrophic

   damage to a bundle of wires (but did not set

   the airplane on fire). The answer for these

   airplanes is a new breaker (VERY expensive) that

   can detect both hard faults (shorts and overloads)

   and soft faults (arcing). Swissair 111 would probably

   not have suffered its fate had the faulted wire

   bundles not been routed adjacent to flammable

   insulation.



   Does anyone have flammable insulation in their

   RV?



   One cannot know the thinking behind selection

   of this wire 30+ years ago. The military and

   commercial aviation communities were wrestling

   with some perceived shortfalls in the insulation

   of choice for the era and the new kids on the

   block . . . Teflon and cousins showed a lot of

   promise.



   Some folks made some terrible, expensive choices.

   Don't know how many accidents were caused but

   I do know of entire fleets of military aircraft

   that were totally re-wired after carrier

   based versions contracted dandruff of the

   wire bundle and started shedding insulation

   in little flakes.



   I was working with the Gates-Piaggio GP-180 at

   the time Lear was looking hard at Tefzel. An

   export controlled product with strong military

   implications. I was ready to go with RayChem's

   Spec 55 wire with very nearly the same properties

   of Tefzel and not export controlled . . . but

   about 10-15% more expensive.



   We ultimately acquired the export license and

   the GP-180 was wired in Tefzel . . . and probably

   still is. If it's not wired in Tefzel, then the

   machine has probably fallen victim to knee-jerk

   reactions so common to bombardment by Chicken

   Little worriers without regard to assessment of

   real risk.



   Too many designers, regulators and decision makers for

   modern products are NOT cognizant of history nor are

   they capable of accurate consideration for magnitude

   of risk. Their charter is to drive all risks to zero

   no matter how much it costs.



   Instead they float with the tide of regulations and

   recommendations that flow from a constellation of

   agencies who are paid to   worry . . . and worry

   they do. Present trends plotted into the future

   suggest that risks associated with all forms of

   transportation will be driven to ZERO. It's easy.

   Regulate those systems out of existence with

   constrictions of critical components like fuel,

   unattainable efficiency mandates, traffic flow

   boondoggles and yes . . . insulation on wires.



 

 

   Bob . . .

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nuckolls.bob(at)aeroelect
Guest

Posted: Mon Aug 06, 2012 5:54 am Post subject: Safe Wire Types

At 07:40 AM 8/6/2012, you wrote:

 --> AeroElectric-List message posted by: "racerjerry" <gki(at)suffolk.lib.ny.us>



 I cannot argue with anything that has been said here; however, the real problem lies at the ends of the wire.   



 If you hook up your new Taiwan audio gadget with 20 feet of 24 AWG and connect it to a â€œconvenientâ€ 30 amp circuit breaker, you could find yourself in a would of hurt if the device decides to short out.  The breaker will never trip and the wire will become a smoke generator.  Ask me how I know.



 Common hook-up wire purchased at your local electronics or auto parts store that has PVC insulation will get things over with quicker.  



 Fortunately, my experience was in a service truck and not in a confined RV cockpit at altitude.  By the time I could get the truck stopped at the side of the road, I was totally helpless and on the ground choking.



 --------

 Jerry King



     Sure. This is why it's important not to loose

     sight of the whole system by getting distracted

     with features of one component. Breakers will do

     their job to keep a wire from burning ASSUMING it

     is properly sized to the task. Blaming the cloud

     of noxious smoke on PVC is rather far down the

     chain of events.



     I doubt that the wreckage of Swissair 111 produced

     THE wire that some have hypothesized to have

     ignited nearby insulation. The crew didn't succumb

     to a damaged wire that did not enjoy protection from

     soft faults, it was smoke that was a byproduct of

     another shortfall in selection and installation of

     materials. This report speaks to dozens of incidents

     involving "failures within the entertainment systems"



  http://tinyurl.com/d6rgttp



     but without implicating Tefzel failures as root

     cause. It was Paterson's statement:



 "Tefzel was found in Swiss Air flight SR111's Inflight Entertainment System (IFEN) which was suspected as being the cause of the inflight fire and subsequent crash of the aircraft off Nova Scotia in November 1998." 



     Well duh . . . how does insulation on hookup wire

     figure into the failures within components of

     the in-flight entertainment system? 



     Even if there WAS a faulted wire, had the poor

     choice of insulation not been present, the airplane

     might have simply suffered wire bundle damage like

     the Hawkers.



     The lessons to be studied here go to the notion

     that all accidents are propagated on a string

     of conditions that follow a triggering event.

     It's useful to consider the cost-benefit-risk-

     ratios for eliminating the triggering event but

     foolish to not include contributing conditions

     as well. All of these accidents would have been

     stopped by breaking the chain anywhere. If the

     Swissair 111 incident had not ended sadly, this

     statement from Airbus would have been humorous:



 "Airbus spokeswoman Mary Anne Greczyn says the company has rigorous standards for entertainment and other aircraft systems. Airbus provides extra protection on entertainment system wiring by using sleeves and other materials, she says."



     Protection of wires using sleeves . . . what's up

     with that? Are the entertainment system wires worthy

     of special attention not enjoyed by the rest of the

     wiring in the airplane? Had the folks who first smelled

     the impending failures been old TV technicians, perhaps

     their learned sense of smell would have identified first-

     failure as a capacitor, a resistor or burning ECB

     material. At no place in any article have I found that

     Tefzel wire . . . or any other wire is directly responsible

     for triggering this incident. Yet we see statements

     like . . .



 The aviation industry has been grappling for years with problems of cracked and deteriorated wiring causing fires and emergency landings, he says. Adding four miles of entertainment system wire to a jet that may have more than 100 miles of other wires is "like throwing gas on a fire." 



 Lacey believes planes are safer without the systems. "We could choose to do without fancy entertainment systems," he says. "A good book works for me."



     Fine examples of Chicken Little journalism and

     arm-chair, bureaucratic accident analysis. I've not

     seen any direct evidence that this incident (or

     dozens of others) would have been prevented by

     replacing the Tefzel wire . . .



     Tens of thousands of airplanes are flying with

     PVC insulated wires . . . many of which are fed

     by appropriately sized breakers that performed

     as advertised and opened up without so much as

     melting the insulation much less setting it on fire.



 

   Bob . . .    [quote][b]

stein(at)steinair.com
Guest

Posted: Mon Aug 06, 2012 7:12 am Post subject: Safe Wire Types

Total waste of time to try and even acquire much less use that wire on a small piston single plane.  Wires in our planes are not carrying high Hz AC voltage like the heavy iron I used to work with.  As Bob has said repeatedly, stick with regular Tefzel and you’ll be golden. Yes there is that one guy that has the one website that has been out there forever written by a person with subjective personal and political motivation, and some of the info is dubious (some of it is outright conjecture) to begin with and also much of it doesn’t apply to systems in our planes.  Just because someone put something on a webpage somewhere sometime and claims to be an expert does not make it so. Stick with what works well for your installation and don’t try to turn your plane into a Boeing!

 

Just my 2 cents as usual.

 

Cheers,

 

Stein

 

 



 

From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Marvin Dorris Jr

Sent: Sunday, August 05, 2012 5:38 PM

To: aeroelectric-list(at)matronics.com

Subject: RE: Safe Wire Types

 

 

If you're building a new airplane, use TKT Boeing or maybe TKT Airbus.  If you have to fly in something older, or something that doesn't have these types of wire, and something happens, blame your aviation safety advisor if you lose people.

 

And I'm thinking of buying a 1960 Bonanza Debonair??????????

 

Best Regards to All,

 





 

 	  Quote: 	
		   Subject: Safe Wire Types

 From: jimhausch(at)gmail.com (jimhausch(at)gmail.com)

 Date: Sun, 5 Aug 2012 13:28:56 -0700

 To: aeroelectric-list(at)matronics.com (aeroelectric-list(at)matronics.com)

 

 --> AeroElectric-List message posted by: "jhausch" <jimhausch(at)gmail.com (jimhausch(at)gmail.com)>

 

 Ran across this link. Did some searching here to see if posted previously, but that does not seem to be the case.

 

 Anyone's thoughts on this?

 http://www.vision.net.au/~apaterson/aviation/wire_types.htm

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=380111#380111

 

 

 

 

 

 

==============

 

 

 


	


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  [quote][b]

jhausch

Joined: 14 Jan 2008
Posts: 35

Posted: Tue Aug 07, 2012 12:19 am Post subject: Re: Safe Wire Types

THis has been very informative.  Thanks to all who have replied.  I expected folks to say Tefzel was AOK, but did not expect to see good comments about PVC.



Again, thanks.  very interesting to read (and learn)

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