New A&P - TSO questions...

PMA?? For an owner produced part? Not that I've ever seen or read of.
Ever see an owner produce a throttle or mixture cable?

let's keep it real.
 
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.
That device is called a cable nut.

http://www.aircraftspruce.com/catalog/appages/cablendbnut.php?clickkey=20916

And for the cable housing is secured by a Adel clamp, nuts and bolts
 
Ever see an owner produce a throttle or mixture cable?
.
No. But I think the question was if he could do it? However, I have seen owner produced engine cowls, doors, spars, structural fittings, flap tracks, actuator housings, landing gear fittings, skid tubes, etc........ So it's real. I agree you don't see it a lot in the GA world but it does occur. However, in the rest of the industry it is a common viable option depending on the company and abilities.
 
Yeah, I replaced the cushion clamps the previous owner had on there with the AN472 style. The existing mixture control doesn't have the cable nut. But, I'll be sure and add one on the new cable. Thanks!
I build a better one, stop by. :)
 
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.

I went and dug up the applicable FAA orders to see what you and Tom were telling me here. Ref 8120-22A Production Approval Procedures, it actually does say, "The TSO authorization is both an FAA design and production approval . . . " I get it that a TSO is not an installation approval. In my regular airline job, I've dug through a lot of TSOs and the specifications they point to understand system design requirements. I never recognized the the production approval aspect.
 
Ever see an owner produce a throttle or mixture cable?

let's keep it real.
Well, by reading the letter from the FAA Chief Counsel (the feller that defined the "owner produced part" opinion) you can buy a part, modify it, and it qualifies as an "owner produced part". Reading the letter carefully, ANY modification will qualify. So, if I buy a 6' cable and cut 2' off of it to fit my aircraft (along with an engineering drawing of the cut) it qualifies. Yes, I have seen an owner produced engine cable.

Jim
 
Well, by reading the letter from the FAA Chief Counsel (the feller that defined the "owner produced part" opinion) you can buy a part, modify it, and it qualifies as an "owner produced part". Reading the letter carefully, ANY modification will qualify. So, if I buy a 6' cable and cut 2' off of it to fit my aircraft (along with an engineering drawing of the cut) it qualifies. Yes, I have seen an owner produced engine cable.

Jim
Jim you go right ahead and go with that idea. The correct throttle and mixture cables for a PA-28 are readily available, I'll insist that they buy the right stuff.
 
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