Wire mis-calc

[TMann]

One of our EAA Chapter members was beaming at a meeting a couple months ago. His RV was complete and he had an appointment for his inspection. The goal was to provide a flight test report for our next chapter meeting.

 

Well ........ that did not happen. In an effort to save time and money, he used auto wire vs. FAA approved wire. He is now in the process of pulling all of his wiring and replacing it with the required replacement.

 

It really has taken the wind out of his sails as he struggles to get motivated and keep pushing forward.

 

It's a heartbreaker of an experience for him but a good heads up for any builders out there.

[Lynn Erickson]

One of our EAA Chapter members was beaming at a meeting a couple months ago. His RV was complete and he had an appointment for his inspection. The goal was to provide a flight test report for our next chapter meeting.

 

Well ........ that did not happen. In an effort to save time and money, he used auto wire vs. FAA approved wire. He is now in the process of pulling all of his wiring and replacing it with the required replacement.

 

It really has taken the wind out of his sails as he struggles to get motivated and keep pushing forward.

 

It's a heartbreaker of an experience for him but a good heads up for any builders out there.

Did they tell him he had to change it or just suggest it. there are many homebuilts flying that used good quailty auto wire

[TMann]

Remove & Replace is required according to the inspector.

[mplafleur]

The FAA has approved wire?

 

That's news to me.

 

Show me the reg that requires this.

[TMann]

The FAA has approved wire?

 

That's news to me.

 

Show me the reg that requires this.

Perhaps I phrased that wrong.

The FAA rep would not approve the wire used. (i.e. not FAA approved)

 

Our meeting is Monday so I'll try and get some specifics.

Point being, this is an area that takes a considerable amout of time. For that reason, it is not an area to try and get by on the cheap when it comes to the materials used.

Agreed?

[Lynn Erickson]

Perhaps I phrased that wrong.

The FAA rep would not approve the wire used. (i.e. not FAA approved)

 

Our meeting is Monday so I'll try and get some specifics.

Point being, this is an area that takes a considerable amout of time. For that reason, it is not an area to try and get by on the cheap when it comes to the materials used.

Agreed?

is the FAA rep a DAR or the FAA? the manufacturer says if the materials are airworthy not the FAA. they don't tell you which engine you can use so why what kind of wire. maybe thats his experiment, to see if that kind of wire will work in an airplane. he may have used wire that was not the best chioce but if it was done in an airworthy manner that is what the FAA should be looking at. I have seen a homebuilt that was done with surplus wire and had no less then 5 butt splices in each wire but it passed because the splices where done in an airworthy manner.

[mak790]

For everybody who have doubts why we should use proper aircraft quality materials instead of cheaper ones read this short NTSB report, E-Racer pilot and passenger paid the highest price for it.

 

Witnesses reported seeing the aircraft flying over the departure end of the runway, at approximately 400 feet agl and observed a momentary pitch oscillation as the aircraft entered a steeply banked left turn. The aircraft continued in the turn, descending gradually toward the ground until impact. The witnesses described the engine sounds as 'unusually loud.' The carburetor throttle body was found in a nearly full-open position while the cockpit twist grip throttle control linkage was found separated at a ball swivel fitting. The throttle grip was found separated from the twist grip throttle. The throttle linkage parts were reportedly not aircraft quality materials.

Mak

[Waiter]

I've personally seen several projects over the years that were good quality "glass" work, but obviously, the builder didn't know anything about electrical, and didn't seek guidance.

 

One particular case, I was asked to perform a prepurchase inspection and provide flight instruction to the new owner (VariViggen). When we opened the cowling and inspection hatches, I found extensive use of "Bell Wire" (The stuff they use to wire home door bells with).

 

I told the new owner that all the solid wire needed to be replaced with "Aviation" wire before "we" would fly the plane.

 

In this case, Solid wire , when used in an application with any vibration, will crack and break, randomly. (The old owner had indicated that over the years he found a several wire breaks and had repaired them).

 

This is a classic case of "Knowing what you don't know" then getting professional guidance.

 

With todays ability to access the INTERNET, there simply is no excuse.

 

Look at Stien Air, ACS, WICKS, etc, etc. Learn a little about Mil-Spec.

 

Waiter

[Richard Schubert]

For the actual reports see:

 

http://www.ntsb.gov/ntsb/GenPDF.asp?id=LAX94LA177&rpt=fa

 

http://www.ntsb.gov/ntsb/GenPDF.asp?id=LAX94LA177&rpt=fi

 

I will add that nobody has ever been killed by a certified part

[mak790]

I will add that nobody has ever been killed by a certified part

Of course I agree with you (most accidents were caused by certified engine troubles-lost power) but message was it's safer to use proper parts then others. In theory aircraft parts should be made of better quality materials. How it looks in practice I don't know ask Marc.

 

Mak

[TMann]

I will add that nobody has ever been killed by a certified part

Well .......... let's just say that the odds get a lot better with the quality of the part.

Point being that an 'on the cheap' philosophy doesn't tend to keep you 'on the scope'.

[mplafleur]

For the actual reports see:

 

http://www.ntsb.gov/ntsb/GenPDF.asp?id=LAX94LA177&rpt=fa

 

http://www.ntsb.gov/ntsb/GenPDF.asp?id=LAX94LA177&rpt=fi

 

I will add that nobody has ever been killed by a certified part

You say that sarcastically, I hope.

[Big Steve]

Just to throw gas on the fire. If you cannot fly with automotive wire you should not be able to fly with an automotive motor either???? I thought these things were licensed as experimental does that go for the wire and everything else? Who is this supposed faa guy that makes these kinds of decisions on an "experimental" airplane. I know there are some things that just should not be put in an airplane but who am I to tell someone else what he can do with his experimental plane.

[chasingmars]

Regardless of whether the DAR/whomever has the legal authority to *make* him take it out (and not knowing exactly what he did use), if it's solid core or PVC insulated or whatever, it's a awfully good idea to do so, isn't it?

 

I'm not sure exactly what your rules are in the States, I know there's more flexibility, here, the inspector can say "that doesn't meet this or that design practice" and you have to correct it (or at least, show that your method is equal or better), I gather. For example, my firewall can't be plans aluminium, I'm told.

[Big Steve]

After thinking about my above semi tirade. I thought there are things that if someone did not know better it would behoove us to try and talk them out of it like solid wires that brake and obvious things that maybe someone who had never built a plane would not understand. I still stand by the fact that the government should not be able to protect my from my stupid self. It is my life. Enough said I hijacked this thread enough. STEVE

[TMann]

As I stated earlier, I have my chapter meeting Monday and I should get more info as to what is going on with his project.

I don't have the specifics. It could be he was using solid core wire or the wrong guage. Maybe it was the insulation.

 

I'll post more info after the meeting.

[macleodm3]

I still stand by the fact that the government should not be able to protect my from my stupid self.

I agree with you Steve. Unfortunately, a large chunk of our population is leaning toward the opposite. It seams that our society thinks we have the right to always be protected and that if anything bad happens, the "institution" involved should have prevented it. The Very First Day of the Virginia Tech shootings, the media was trying to blame the university. As soon as the bridge collapsed in Minneapolis, blame is the name of the game. Hurricane Katrina is only about blame, blame, blame.

 

If I had to inspect your aircraft as a govenment official, then I too would Know that if anything ever happened to your aircraft... that our society would Blame the inspector for not catching the fact you didn't use aircraft wire (or whatever it happened to be).

 

The government agencies that I do business are scared to death of approving any type of engineering design that they haven't seen many, many times. No flexibility At All. I can understand the situation involoving the wire... and I expect to see a lot more of it in the future.

 

I don't like it though. I believe that this should be experimental aviation, not certified on different level.

[Cozy1200]

Unfortunately, a large chunk of our population is leaning toward the opposite. It seams that our society thinks we have the right to always be protected and that if anything bad happens, the "institution" involved should have prevented it.

Seeing that we're heading off topic, I might as well join in.

 

Living as in "outsider" in Australia, I'm constantly amazed at the "freedoms" that Australians are willing to give up in the name of "being Safe", "for the good of the people", or "not to be like the bad traits of America".

 

I only half-jokingly tell my friends here that:

 

"We American still value our rights, even if it is the right to be stupid"

[Richard Schubert]

quote:

Originally Posted by mplafleur

You say that sarcastically, I hope.

Sorry, I couldn't find the sarcastic smiley

 

I also agree that the appropriate materials and parts should be used.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:

 

the failure of the pilot to maintain control of the aircraft (my emphasis) while maneuvering in the traffic pattern following a failure of the throttle control. A factor in the accident was a throttle linkage separation after takeoff.

Being an E-racer builder, I reserve the right to nitpick

 

NTSB factual

The throttle linkage parts were not aircraft quality materials according to the designer of the aircraft

Curious, since the designer used the same system (motorcycle throttle twist grip on center stick) on the prototype.

 

Originally Posted by chasingmars

For example, my firewall can't be plans aluminium, I'm told.

The aluminum only serves as a protective shield for the fiberfrax, which is the actual firewall

[TMann]

I don't think that the purpose of the FAA inspection/sign-off is for the benefit of the pilot as much as it is for the safety of the population on the ground (i.e. 1 pilot vs. the population of an apartment building?)

 

It's a small concession to submit to considering we have been given the freedom to actually build our own planes.

Could be worse. I don't think our founding fathers had aviation in mind when they wrote the constitution (well maybe Jeffersen did .)

[macleodm3]

Very True. It really is great that we're allowed to build our own airplanes and fly them around at 200 mph. I'll also learn from this and make sure I use the correct wire when the time comes.

[Jack Morrison]

I had the same throttle setup in my E Racer during high speed taxi testing and it failed (froze) on returning to my hanger, only in the idle position. Needless to say, it was trashed the next day and replaced with an aviation quality cable and system.

Shirl had that system on the proto type E Racer for many years.

 

Jack

E Racer 113

[chasingmars]

=

The aluminum only serves as a protective shield for the fiberfrax, which is the actual firewall

That line of argument might work... the item in question is:

(24) Each enclosed engine compartment shall be isolated from the remainder of the aircraft by a firewall, which shall be made of fireproof material.

Or, it might not. I'm keeping an eye out for 18 mil titanium sheet in a large enough piece

[Spodman]

For example, my firewall can't be plans aluminium, I'm told...The aluminum only serves as a protective shield for the fiberfrax, which is the actual firewall

I understand the metal bit, whatever it is called, is supposed to be stainless steel, as per the templates, rather than Al, as in the materials list.

 

I recall a similar discussion about LED position lights which an FAA drone wouldn't approve. I gather once one inspector has made a ruling you have no hope of getting another to be reasonable.

 

Despite having given away all our freedoms to own machine guns, etc. we have the option here of fending off the FAA-equivilant inspector and running with an accredited person from the SAAA (our EAA) & getting him in along the course of the project (not required, but useful) so such things can be discussed along the way rather than shouted over an aircraft you think is ready to fly. Isn't it similar there???

[TMann]

I spoke with the individual at our chapter meeting last night. I'm getting the impression there is more to this than just the information he's giving up. He seemed to be pretty evasive.

 

Another builder said that along with questionable materials, the wires were looking a lot like a rat's nest. It appears that this got the FAA examiner in a real bad mood and the rest of the inspection went downhill from there.