New A&P - TSO questions...

If done as a replacement part or minor alteration how did the FSDO find out?

Bingo. If the FSDO is looking that closely at my airplane, I've already got bigger problems.
 
Interesting read...what I’ve gathered from this thread so far is that the EGT/CHT gauge may be fine...

I missed that it is a dual gauge. That may be a problem. CHT is required in CAR3 (basis of certification) I believe.

Just got to love all the little gotcha's in aviation!
 
Yea I don't disagree...more just curious at this point to look at logs/history and see how these were installed and if there is a 337,etc. Good learning experience I guess.

I like your attitude. Good on ya! :)
 
I missed that it is a dual gauge. That may be a problem. CHT is required in CAR3 (basis of certification) I believe.

Just got to love all the little gotcha's in aviation!

Hmm..alright. Not sure if things are more clear after this thread or if I am more confused haha
 
Hmm..alright. Not sure if things are more clear after this thread or if I am more confused haha

Do your own research, pick a path you can live with and move on. About all you can do.
 
spot check....while it was in for an annual at the FBO. o_O

Just have to look in the window. A vernier throttle knob installed in an older Cherokee where the OEM is just a big fat knob. That starts the ball rolling.
 
spot check....while it was in for an annual at the FBO
Interesting. So the ASI was at the FBO for a routine surveillance visit (?) and by chance walked by your aircraft and noted the “improper” engine control?

Did he notify you in writing of this issue? If so, was it an Aircraft Condition Notice or a Letter of Correction? And what was the FAA rule that was referenced for the improper controls?
 
that's the story I gots......I have a feeling there might be more to the story though.

I think the DoM called me and then I called the FSDO. I don't recall the reg that was referenced, only that the vernier controls on my Six were not legit. I worked with the FSDO and was able to clear up the conformity with a field approval using a 337.
 
Just have to look in the window.
Most ASIs don't unless there was a previous report, a safety-of-flight issue, or other important reason mainly due to the FAA paperwork involved to pursue the matter.
 
that's the story I gots......I have a feeling there might be more to the story though.
Well if you didn't get something in writing from the FAA as the aircraft owner... there is a specific process that must be followed. Was it the FBO's recommendation you get a 337? The FAA has the burden of proof by reference to show why the aircraft is not airworthy not the other way around. Without knowing more, sounds like the FBO had issues with the controls first.
 
Well if you didn't get something in writing from the FAA as the aircraft owner... there is a specific process that must be followed. Was it the FBO's recommendation you get a 337? The FAA has the burden of proof by reference to show why the aircraft is not airworthy not the other way around. Without knowing more, sounds like the FBO had issues with the controls first.
I was notified....it was +10 years ago. I suspected the FBO didn't like previous IAs and got him in a pezzing contest with the FSDO....and I was caught in the cross fire.
 
I was caught in the cross fire.
Those are never good situations. I've been brought in a few times to similar situations to help work out a solution, but nobody ever wins that game. But for future FYI, anytime the Feds "point a finger" your way ask for their response in writing. It's required per their internal procedures. Technically, it's called a "Letter of Correction" in FAA lingo. Just tell them it's for your records and you want to ensure the proper logbook entry is made to correct it.
 
I missed that it is a dual gauge. That may be a problem. CHT is required in CAR3 (basis of certification) I believe.

Just got to love all the little gotcha's in aviation!

nope cht was not a required instrument his PA28
bob
 
Those are never good situations. I've been brought in a few times to similar situations to help work out a solution, but nobody ever wins that game. But for future FYI, anytime the Feds "point a finger" your way ask for their response in writing. It's required per their internal procedures. Technically, it's called a "Letter of Correction" in FAA lingo. Just tell them it's for your records and you want to ensure the proper logbook entry is made to correct it.
I have found that when the FAA (agent) is talking to you, be nice, because when they stop talking they start writing, that is when things get serious.
If they are really after your Azz, the first thing you see is a registered must sign for letter.
 
I got a letter. :confused:
Those are never good situations. I've been brought in a few times to similar situations to help work out a solution, but nobody ever wins that game. But for future FYI, anytime the Feds "point a finger" your way ask for their response in writing. It's required per their internal procedures. Technically, it's called a "Letter of Correction" in FAA lingo. Just tell them it's for your records and you want to ensure the proper logbook entry is made to correct it.
 
Not that anyone really cares, but we dumped that guy and found another A&P who was recommended. Nice guy and seems genuinely interested in working on the airplane and doing an owner assisted annual in May. After some further phone calls with the previous A&P, we found he was nothing short of a complete azzhole and could care less about working on our airplane. Seems like a bizarre way to run a business, but I guess if he has plenty of airplanes to work on it doesn't matter.
 
Seems like a bizarre way to run a business, but I guess if he has plenty of airplanes to work on it doesn't matter.

Thanks for following up!

Unfortunately this seems all to common...
 
An A&P installed a McFarlane verneer mixture cable in my 182.

Log book entry was something like.... replaced Mixture control with McFarlane PMA part #1234 in accordance with Cessna maintenance manual.

The McFarlane name and part number are roll marked on the part.
 
I saw a lot of stuff in this thread that I do not agree with. Here is how I understand things.

First, when I need to review what an approved part is, I refer to AC 20-62 Eligibility, Quality, and Identification of Aeronautical Replacement Parts.

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From the FAA's page -> A Technical Standard Order (TSO) is a minimum performance standard issued by the Administrator for specified materials, parts, processes, and appliances used on civil aircraft.

What does that mean? I own a part 23 aircraft, that is the FAA certified (with a Type Certificate) that it meets part 23 rules, hence the configuration is approved.

If it's maintained in a safe condition it is considered airworthy (Far 3.5).

If I want to operate it in domestic US airspace I have to comply within operational rules and equipage requirements laid out in part 91.

Now, part 91 says I need to have a transponder to operate where I want to operate. There are several options (types and classes), but what is the actual definition of a transponder? The way the FAA handles that definition is by creating a TSO that describes the Minimum Operational Performance Requirements of a transponder. A transponder is a complex communication device that needs to be compatible with equipment air traffic control uses to track aircraft, send out GPS signals, interact with TCAS systems etc. It's hugely complex. The reality is the FAA's TSO points to RTCA documents (that are huge) to describe the Minimum Operating Performance Standards for a transponder.

If you are a transponder manufacturer and want the FAA and potential customers to recognize that you have built a transponder that meets all of the minimum requirements (so you can build, sell and obtain approval to install it on certified aircraft), you do all the testing and obtain a TSO approval from the FAA. Avionics manufacturers do that all the time as Part 21(?) manufacturers. Once you have the TSO, you can put that information on your data plate. Now, people that want to buy and install a device they know complies with all the operational requirements can just buy one that is TSO XXX approved.

I looked and didn't see where the FAA issued a TSO for throttles. Chances are it just needs to be an approved part. There are probably part 23 certification standards that drove the design of the original aircraft throttle. The aircraft manufacturer had to comply with the rules and meet those throttle requirements when the original aircraft was designed and certified. If that is the case, the OEM's design and manufacturing data describes what the approved replacement part should look like and possibly how it should be made.

Anyone else that wants to manufacture and sell a part as a replacement for the original aircraft part needs approval from the FAA (MIDO- Manufacturing and Inspection District Office) to do that. There are way of obtaining a PMA to manufacture a replacement part, with and without the original OEM's intellectual property. A PMA shows you are approved, have the necessary tools, knowledge, quality controls, the necessary design data, and keep the necessary records to manufacture that aircraft part.
 
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I saw a lot of stuff in this thread that I do not agree with. Here is how I understand some of it.

When I need to review what an approved part is, I refer to AC 20-62 Eligibility, Quality, and Identification of Aeronautical Replacement Parts.

ecblank.gif

From the FAA's page -> A Technical Standard Order (TSO) is a minimum performance standard issued by the Administrator for specified materials, parts, processes, and appliances used on civil aircraft.

What does that mean? I own a part 23 aircraft, that is the FAA certified (with a Type Certificate) that it meets part 23 rules for airworthiness, and is now would be considered safe enough by the FAA for them to issue an airworthiness certificate.

I want to operate it in domestic US airspace which means I have to comply with operational rules and equipage requirements laid out in part 91.

Part 91 says I need to have a transponder. Lets talk transponders. There are several options, but what is the definition of a transponder? The way the FAA handles that is they have a TSO that describes the Minimum Operational Performance Requirements of a transponder. A transponder is a complex communication device that needs to be compatible with equipment air traffic control uses to track aircraft, send out GPS signals, interact with TCAS systems etc. It's hugely complex..

If you are a transponder manufacturer and want the FAA and potential customers to recognize that you have built a transponder that meets all of the minimum requirements (so you can sell the thing and easily obtain approval to install it on an aircraft), you do all the testing required and obtain a TSO approval from the FAA. Once you have that, you can put that information on your data plate. Now, people that want to buy and install a device they know complies with all the operational requirements can just buy one that meets the required TSO.

I looked and didn't see where the FAA issued any TSOs for throttles. Chances are it just needs to be an approved part. There are probably part 23 certification standards that drove the design of the aircraft throttle. The aircraft manufacturer had to comply with the rules and meet those throttle requirements when the original aircraft was designed and certified. If that is the case, the OEM's design and manufacturing data describes what the approved replacement part should look like and possibly how it should be made.

Anyone else that wants to manufacture and sell a part as a replacement for the original needs approval from the FAA (MIDO- Manufacturing and Inspection District Office) to do that. There are way of obtaining a PMA to manufacture a replacement part, with and without the original OEM's intellectual property. A PMA shows you are approved, have the necessary quality controls, the necessary design data to manufacture that aircraft part.
If your theory is correct, why doesn't an engine have a TSO?

TSO is normally a order that requires equipment to meet a certain standard or must integrate with other systems. This order will not effect a throttle or mixture cable, they only need to meet PMA to be used as a replacement for a Certified part number that is called out on the Production certificate for this make and model.
Are these cable called out as part number by Piper. ? I have no clue, never looked it up and don't plan to.
You want to nit-pic every aircraft this close? you will never fly again.
Can you prove every rivet in your aircraft met certification when it was used?
 
If your theory is correct, why doesn't an engine have a TSO?
Good question, I believe Engines and Propellers are certified under their own FAR parts.

I don't really understand what it is you dissagree with. The TSO description was a grab from the FAA's web page. Consider it a quote though. The reason I wrote my post was to try to explain the difference between a PMA & a TSO. There used to be a document that provided a comprehensive description of the TSO system on the FAAs webpage someplace.

I'm not sure what you're referring to with nit picking. If I see a rivet that is loose or damaged, perhaps half shaved off, it is damaged and no longer meets design specifications and good maintenance dictates it be replaced, which is what the 4313 generally calls for. So you just shoot a new rivet in? I used to work sheet metal at Eastern Airlines years ago. If an inspector performing an inspection on a heavy check saw a rivet with streaks, indicating it was working loose, they'd just have us replace it.

On certified airplanes, with credible records, I assume it's been maintained with approved parts If I don't have evidence to the contrary. Years ago in Miami, I did work for a Cessna 402 operator that flew to the islands, that had to replace a bunch of fuselage rivets because the FAA inspector couldn't see the dimples in the rivet heads. I don't know if the rivet heads had been sanded down by someone or not.
 
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I looked and didn't see where the FAA issued a TSO for throttles. Chances are it just needs to be an approved part.
But keep in mind a TSOA is a basic production approval and does not provide an installation approval. That must still be determined by the installer. A PMA, STC, PC, and TC are more detailed part production approvals and provide installation approval as well.
 
What if I send McFarlane specs for my throttle cable, as an owner, and they produce it for me? Non PMA, non TSO.
 
What if I send McFarlane specs for my throttle cable, as an owner, and they produce it for me? Non PMA, non TSO.
So long as it is installed on your aircraft, you provide McFarlane with complete specifications/drawings (or the old cable for reverse engineering), they produce a new cable to your specs--not take one off the shelf, and identify the part as an owner part like P/N: Salty-001, you are good to go along as your mechanic will install it. But the part is legal per 21.9(a)(5).
 
But keep in mind a TSOA is a basic production approval and does not provide an installation approval. That must still be determined by the installer. A PMA, STC, PC, and TC are more detailed part production approvals and provide installation approval as well.
Agreed, just because a part meets a TSO or is an acceptable airplane part or has been supplementally certified for installation on one aircraft, does not mean it is OK to install it on all airplanes.
 
Agreed, just because a part meets a TSO or is an acceptable airplane part or has been supplementally certified for installation on one aircraft, does not mean it is OK to install it on all airplanes.
Once again. TSO has nothing to do with installation.
 
The mechanic said we have to take the plane to the landfill, cause it's not certified :( and we have to pay him 20k to take it there.
 
The mechanic said we have to take the plane to the landfill, cause it's not certified :( and we have to pay him 20k to take it there.
don't forget the ferry permit first
 
don't forget the ferry permit first

Ahh yes that will be another 10k. Mechanic also said I have to buy him a flatbed trailer otherwise he won't sign off the annual.
 
I do think consulting with an practicing A&P/IA is an excellent way to find out how the local FSDO interprets the regulations .
Opinionated interpretation of the regulations is a problem.
Some additional references (I paraphrase titles, these may not be the latest)->
AC 23-27_Parts and Materials Substitution for Vintage Aircraft
AC 21-50_Installation of TSOA Articles
AC 20-41A_SUBSTITUTE_TSO_EQUIP
AC 43-18 CHG 2 Fabrication of Parts
 
So long as it is installed on your aircraft, you provide McFarlane with complete specifications/drawings (or the old cable for reverse engineering), they produce a new cable to your specs--not take one off the shelf, and identify the part as an owner part like P/N: Salty-001, you are good to go along as your mechanic will install it. But the part is legal per 21.9(a)(5).
As well as 21.303 (b)(2).

Jim
 
I was looking at replacing the non-vernier mixture control on my Sonerai with a vernier style control. I found a "non-PMA" vernier mixture control that is about 1/2 the price of one with PMA. The only difference that I can see between it and the PMA'd one is that it doesn't have rigid boss to mount at the carb end. You can trim the flexible outer jacket and inner wire core to whatever length you need. But, you have to come up with a way to secure the jacket so it doesn't move on you when you push the control back in. Not difficult to do in my little homebuilt. But, it might be entertaining to see some of the ways it could be mounted on a certified airplane by someone who would do that.
 
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