New A&P - TSO questions...

CC268

CC268

Final Approach
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CC268
Fair warning - I have been reading about TSO, PMA, STC, etc. I have read several threads here on POA about TSO'd, what exactly it means, what is legal, etc. I have read a few threads on other aviation websites as well. There seems to be a lot of polarizing opinions/interpretations on the subject. So...just know I DID NOT post this thread without first reading some similar threads.

Long story short my dad and I have been searching for a new A&P. We scheduled a new A&P to come out and perform the latest Piper AD (regarding the fuel selector) as well as check out the fuel pressure gauge and EGT gauge that I wrote about on here a week or so ago. Our annual is coming up in May, so we told him we may be interested in scheduling the annual with him as well.

***Tangent Warning*** Oddly enough when speaking to him on the phone we told him we do our best to keep our Cherokee well maintained and that we have had fairly straight forward annuals the past few years. We try to do owner assisted annuals so that we are involved and reduce some of the labor cost. He laughed at the comment and says, "I can't remember the last time I had a straight forward annual. I find a lot of things to fix." It seemed like an odd thing to say...

So yesterday he comes out to the airplane and performs the AD, checks the fuel pressure gauge (which he says is good), and then checks out the EGT gauge.

He sends a text (didn't bother to call?) and says the EGT/CHT gauge is not TSO'd so he won't touch it. Neither is our throttle and mixture knob. He also stated that he wouldn't perform an annual on our plane unless those things were replaced with TSO'd equipment. He did sign off on the AD and said the fuel pressure gauge was fine.

My dad and I were surprised to hear this, as we had a very thorough pre-buy done on this airplane (3 years ago) and that was not brought up then. No A&P has ever said anything about it in past annuals either (and we have had two different A&Ps do the annual as our regular A&P was not available at the time). In fact, every mechanic that has ever laid hands on the thing has said it was one of the nicest and most well maintained Cherokee's they have ever worked on. We will replace the parts if need be, as we don't want any trouble with the FAA, but it does seem a little odd that no one who has worked on this airplane (several mechanics, avionics shop, etc) has ever said a word about these things not being TSO'd.

This airplane was basically rebuilt in 2010 - it is a real surprise to us that these non-TSO'd parts were used.

So...were going to have another A&P come out and take a look at all this, but what are your guys' thoughts on this?

We are doing our best to do our due diligence and make sure we are within compliance.
 
Do you have more info about the EGT gauge?
 
It's not uncommon for work to be done and parts replaced on older airplanes that isn't compliant. Most A&P's either don't notice or don't care realizing it's an older airplane and has been flying that way for a while. Others follow the letter of the law, just depends on what type of A&P you want working on your airplane.

My father discovered last week a Cub had been flying around for years with an unapproved propeller and engine. Been installed for over 10 years and no A&P nor IA ever noticed.
 
Grum.Man said:
It's not uncommon for work to be done and parts replaced on older airplanes that isn't compliant. Most A&P's either don't notice or don't care realizing it's an older airplane and has been flying that way for a while. Others follow the letter of the law, just depends on what type of A&P you want working on your airplane.

My father discovered last week a Cub had been flying around for years with an unapproved propeller and engine. Been installed for over 10 years and no A&P nor IA ever noticed.
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Yea...I mean that is kind of what I figured. If I am looking at the right PNs online it looks like the Piper mixture and throttle control are not horribly expensive. Haven't looked into the possibilities for the EGT/CHT gauge
 
Some A&P-IAs pride themselves on being nit-pickers, you did right to get another A&P.
Anytime any A&P says something like he did, ask them to show the FAR requirement for such things.
And when they can't, say "have a nice day, bye bye"
 
No one mechanic can know everything. Either this guy is wrong, or the 3 mechanics prior didn’t know enough or care enough to catch it. My guess is, the guy is probably right. Educated guess (school of hard knocks).

I want a mechanic that catches and fixes things properly so that the plane is airworthy from a safety standpoint (regulatory, sure, but primarily safety). The trick is finding that guy.

I’ve had my pre-buy & annual A&P at a rural airport who was my type specific expert (Peterson conversion), my trunk of car A&P who is a generalist, and my expensive pro-shop who knows older Cessnas. They each get my business depending on what I need. I’m still learning.
 
Lots of replacement parts are built upon a Parts manufacturing Approval, but are never TSO'ed.
Simply because there was never a TSO instruction written. Knobs are probably like that.
 
455 Bravo Uniform said:
No one mechanic can know everything. Either this guy is wrong, or the 3 mechanics prior didn’t know enough or care enough to catch it. My guess is, the guy is probably right. Educated guess (school of hard knocks).

I want a mechanic that catches and fixes things properly so that the plane is airworthy from a safety standpoint (regulatory, sure, but primarily safety). The trick is finding that guy.

I’ve had my pre-buy & annual A&P at a rural airport who was my type specific expert (Peterson conversion), my trunk of car A&P who is a generalist, and my expensive pro-shop who knows older Cessnas. They each get my business depending on what I need. I’m still learning.
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Yea...I mean I don't think the mixture and throttle control are a safety issue. I could be wrong. The mechanics who worked on our plane before certainly aren't careless, but maybe your right that they don't care enough to catch it.

We of course want an "airworthy" plane. But when someone says, "I've never had a straight forward annual. I find lots of things to fix"...an alarm goes off. Is this guy looking for my best interest or is he just reaching into my pockets?
 
I’d find an Ap that doesn’t think you’re plane is going to crash if the egt isn’t Tsod
 
455 Bravo Uniform said:
No one mechanic can know everything. Either this guy is wrong, or the 3 mechanics prior didn’t know enough or care enough to catch it. My guess is, the guy is probably right.
Click to expand...
I wonder if he would insist on radios be TSO'ed
 
Salty said:
I’d find an Ap that doesn’t think you’re plane is going to crash if the egt isn’t Tsod
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Hahaha.

I think I’m more frustrated with just how he presented himself throughout the process.
 
Some A+P s will install parts,and note in the log book they are installing owner provided parts,in older airplanes
 
Tom-D said:
Some A&P-IAs pride themselves on being nit-pickers, you did right to get another A&P.
Anytime any A&P says something like he did, ask them to show the FAR requirement for such things.
And when they can't, say "have a nice day, bye bye"
Click to expand...
CC268 said:
Yea...I mean I don't think the mixture and throttle control are a safety issue. I could be wrong. The mechanics who worked on our plane before certainly aren't careless, but maybe your right that they don't care enough to catch it.

We of course want an "airworthy" plane. But when someone says, "I've never had a straight forward annual. I find lots of things to fix"...an alarm goes off. Is this guy looking for my best interest or is he just reaching into my pockets?
Click to expand...

Keep in mind that the first annual with a new mechanic is most likely going to be the most thorough as he now owns all the mistakes past people have made until the next annual is done by someone different. If your plane goes down off the end of the runway because the throttle cable snapped and the engine went to idle and the FAA finds that they weren't TSO'd, that is his butt on the line. It all sounds petty until something goes wrong then everything gets scrutinized.
 
Grum.Man said:
Keep in mind that the first annual with a new mechanic is most likely going to be the most thorough as he now owns all the mistakes past people have made until the next annual is done by someone different. If your plane goes down off the end of the runway because the throttle cable snapped and the engine went to idle and the FAA finds that they weren't TSO'd, that is his butt on the line. It all sounds petty until something goes wrong then everything gets scrutinized.
Click to expand...

Yea I totally understand that. We’re not opposed to replacing the throttle cable or mixture cable if needed
 
CC268 said:
Yea I totally understand that. We’re not opposed to replacing the throttle cable or mixture cable if needed
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Sounds like "if needed" basically means you decide to have this guy do the annual.
 
TSO engine controls? WTF? Is there such a thing?
 
CC268 said:
He also stated that he wouldn't perform an annual on our plane unless those things were replaced with TSO'd equipment.
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To echo similar comments above, his statement is only a personal opinion when it comes to TSO items not a regulatory issue. And he is entitled to that opinion. There are other means of part approval that work for "replacement parts" and each type of part may have several methods. However, to simply state he wants a TSO knob etc without a "why" explanation, I think you did right in getting another opinion. Besides there are only so many TSOs written and I don't recall seeing a TSO on aircraft knobs lately.

In the future, if a mechanic questions or declares something not right on your plane ask them to provide the reference.
 
I think by the guy saying, "I've never had a straight forward annual. I find lots of things to fix" is probably better than him saying, "Many mechanics who've worked on planes after me tend to find a lot of stuff I missed." I think that he is simply trying to instill confidence in himself rather than scare you into paying a lot of money. Just my opinion and worth exactly what you paid for it. However, nit picking a freakin' knob isn't what I want my mechanic to do. Don't rule him out, give him a chance to explain his opinion and show the regulations that back it up. He may be right, but then again he may realize that the knobs are okay.
 
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Bell206 said:
To echo similar comments above, his statement is only a personal opinion when it comes to TSO items not a regulatory issue. And he is entitled to that opinion. There are other means of part approval that work for "replacement parts" and each type of part may have several methods. However, to simply state he wants a TSO knob etc without a "why" explanation, I think you did right in getting another opinion. Besides there are only so many TSOs written and I don't recall seeing a TSO on aircraft knobs lately.

In the future, if a mechanic questions or declares something not right on your plane ask them to provide the reference.
Click to expand...

Thanks - definitely should have asked him for some references. I understand he is trying to cover his back and he is obviously quite detailed (which isn't a bad thing).
 
bnt83 said:
TSO engine controls? WTF? Is there such a thing?
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EDIT: so...I searched the TSO database and can't find a TSO for throttle or mixture controls...but maybe I am looking in the wrong place?
 
The A&P said if there is a 337 then he is fine with them, which makes sense. I will have to look back and see if there was a 337 done for any of these things.
 
CC268 said:
EDIT: so...I searched the TSO database and can't find a TSO for throttle or mixture controls...but maybe I am looking in the wrong place?
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Aircraft Spruce list both experimental and TSO throttle controls.
 
Grum.Man said:
Aircraft Spruce list both experimental and TSO throttle controls.
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Hmm...alright. I was just looking at the Piper Throttle and Mixture controls on there and no mention of TSO, but alright I guess there is one then.

It mentions FAA approval and PMA on another site
 
CC268 said:
Hmm...alright. I was just looking at the Piper Throttle and Mixture controls on there and no mention of TSO, but alright I guess there is one then.

It mentions FAA approval and PMA on another site
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You're going to drive yourself crazy doing this type of search. How do you know if this mechanic even has a valid point? You're burning a lot of bandwidth for what? Forget the "TSO" issue for the moment. Remember there was no problem before this mechanic showed up. So...

What are your questions at this point?
 
Bell206 said:
You're going to drive yourself crazy doing this type of search. How do you know if this mechanic even has a valid point? You're burning a lot of bandwidth for what? Forget the "TSO" issue for the moment. Remember there was no problem before this mechanic showed up. So...

What are your questions at this point?
Click to expand...

I agree with you...were not going to continue with this A&P. We will find someone else. Just trying to educate myself on this as much as possible. Unfortunately it isn’t exactly a clear cut topic.
 
CC268 said:
The A&P said if there is a 337 then he is fine with them, which makes sense. I will have to look back and see if there was a 337 done for any of these things.
Click to expand...
Is replacement with a non-original throttle cable considered an alteration?
 
Bell206 said:
.

So let's keep it on point. List the question(s) specific to your aircraft and part(s) you are researching?
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So he basically stated the following things were not TSO'd:

1. Mixture control - I don't know the MFG, PN, etc - I would have to look when I get out to the airplane
2. Throttle control - same as above - I can take a look when I get out to the plane later today
3. CHT/EGT gauge - Westach - I believe it is this model (again I can confirm later): https://www.aircraftspruce.com/pages/in/chtgauges_westach/westduals8.php

I mean the A&P is right isn't he? We need TSO'd equipment in our aircraft. Meaning...we need a TSO'd mixture, throttle, and CHT/EGT gauge.

He did say that in some cases the FAA will approve a 337 for an entire panel if it is completely redone (which it was completely redone in 2010). So...like I said I can take a look back and see if this was indeed done and certified.
 
You do need TSO'd mixture and throttle cables....they are required equipment originally part of the TC. The EGT may not be TSO'd IMHO.

Your local FSDO could sign the mixture and throttle cables off (field approval) with a 337....if the mfg has a quality system. I've done this with ACS brand cables. The vernier cables I had signed off were not approved for the particular model but did get the field approval.
 
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Checkout_my_Six said:
You do need TSO'd mixture and throttle cables....they are required equipment originally part of the TC. The EGT may not be TSO'd IMHO.

Your local FSDO could sign the mixture and throttle cables off (field approval) with a 337....if the mfg has a quality system. I've done this. The vernier cables I had signed off were not approved for the particular model but did get the field approval.
Click to expand...

Thanks - the good news is that the TSO'd mixture and throttle cables aren't too expensive.
 
First, look in your aircraft records for any entries covering the 3 items you listed. Be thorough and read each entry. Note any pertinent info.

Second, read this AC on replacement parts and their approval requirements for background info. Every one seems stuck on "TSO." Remember a TSO is only a production specification and not an installation approval. Plus a TSO is not the only option for replacement parts:
http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC 20-62E.pdf

CC268 said:
1. Mixture control - I don't know the MFG, PN, etc - I would have to look when I get out to the airplane
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CC268 said:
2. Throttle control - same as above - I can take a look when I get out to the plane later today
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Just to clarify, by "control" do you mean the airframe cable assembly or something on the engine? Which ever one look for any and all identifying information on the cable assy or whatever. Might even have to get a mirror and look behind the panel.

CC268 said:
3. CHT/EGT gauge - Westach - I believe it is this model (again I can confirm later): https://www.aircraftspruce.com/pages/in/chtgauges_westach/westduals8.php
Click to expand...
Verify P/N of gauge and we'll go from there.

CC268 said:
Thanks - the good news is that the TSO'd mixture and throttle cables aren't too expensive.
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You're getting ahead of the game. What you have may be perfectly legal.....
 
....and to add, just because there is a TSO it still may not be applicable. It really needs a PMA for the installed model aircraft.
 
Bell206 said:
First, look in your aircraft records for any entries covering the 3 items you listed. Be thorough and read each entry. Note any pertinent info.

Second, read this AC on replacement parts and their approval requirements for background info. Every one seems stuck on "TSO." Remember a TSO is only a production specification and not an installation approval. Plus a TSO is not the only option for replacement parts:
http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC 20-62E.pdf



Just to clarify, by "control" do you mean the airframe cable assembly or something on the engine? Which ever one look for any and all identifying information on the cable assy or whatever. Might even have to get a mirror and look behind the panel.


Verify P/N of gauge and we'll go from there.


You're getting ahead of the game. What you have may be perfectly legal.....
Click to expand...

Going flying with my instructor right now, but I got all the answers for you...will report back later.
 
CC268 said:
EDIT: so...I searched the TSO database and can't find a TSO for throttle or mixture controls...but maybe I am looking in the wrong place?
Click to expand...

I would find a different guy.

Now if the guy said you need approved engine controls that would make sense. Unfortunately for him, traceability is rarely kept on file. Cessna, Piper, etc can take any commercially made component that is approved by their type design and ship it to you with a piece of paper, an 8130-3, there my be little to no other identification marks on the part at all, then later in service anyone can claim its not a valid part.

The labels on my brand new McFarlane FAA/PMA cables are going to fall off eventually, does that mean they are aren't approved cables anymore? Hell no it doesn't.
 
bnt83 said:
I would find a different guy.

Now if the guy said you need approved engine controls that would make sense. Unfortunately for him, traceability is rarely kept on file. Cessna, Piper, etc can take any commercially made component that is approved by their type design and ship it to you with a piece of paper, an 8130-3, there my be little to no other identification marks on the part at all, then later in service anyone can claim its not a valid part.

The labels on my brand new McFarlane FAA/PMA cables are going to fall off eventually, does that mean they are aren't approved cables anymore? Hell no it doesn't.
Click to expand...

Really? an 8130-3 with a new part?
I get the rest of it, and agree with the though that the records most owners keep don't last as long as the parts.
 
There is a lot we don't know (as usual) about what the OP has installed or why the new IA baulked at the sight of them.
He may have blue knob on the throttle and a red knob on the prop control.
 
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