Avionics Geeks.

Owner takes his radios out of the plane and walks them to the avionics shop for a bench test. Shop realigns the receiver and gives back to the owner, owner reinstalls into his aircraft. Now the owner finds out he has another problem (weak receive) and calls avionics shop complaining that the shop has caused the problem "because they worked on it".

Owner brings airplane to the shop where the shop now finds 40 year old coax cable and corroded BNC connectors. Shop tells owner the estimate for repairing and owner blows a gasket and demands since the shop worked on the radio then they are required to perform "warranty work".

This is why many shops will not take walk in work from unknown customers. If you want the job done correctly, then the whole aircraft needs to be there so the shop can function test the system in the airplane, then make the necessary adjustments.

But of course you being an avionics tech would know this, right?

Your main premise is mis-stated in the first paragraph. The owner removes the radio for a "bench test". Repeat with emphasis, "BENCH TEST". That can be done in five minutes. But the shop does not stop there, they "realign the receiver". That is an unnecessary hour that purports to fix the problem the owner has. Now they are in fact on the hook for the repair since they did not stop at what the owner asks for. THe simple return of the radio with "bench tests OK" would have saved them a lot of grief.

I was an avionics tech with the airlines all the way through college. After nearly 40 years of avionics engineering I still consider myself a fairly decent avionics tech, yes.

Jim
 
I pretty much agree with all you posted here but I didn't see anything that would allow a pilot (with no A&P) replace a nav head in a certified airplane and then prepare and sign a log entry covering the work and subsequent return to service of the airplane. FAR 43/A is pretty clear that only tray mounted radios in the panel (excluding DME and XPNDR IIRC) can be replaced by a pilot.

FAR 43 even weaselwords this section. THe section you quote only applies (section 30) to "specifically identified as preventive maintenance in a primary category aircraft type certificate or supplemental type certificate holder's approved special inspection ... program..."

There has been a raging legal storm in this country for two hundred years and change. The question revolves around strict and loose construction of the legal system.

Some legal scholars say that what is not prohibited is permitted and other equally brilliant scholars say that what is not permitted is prohibited. You can argue either side of the coin with much evidence on your side.

Strict constructionists say that since changing the oil is not specifically mentioned (even though I can specifically remove, clean, and replace the oil filter) that it is prohibited.

Loose constructionists contend (and I be one of them) that removal and replacement of identical instruments and their minor adjustments are preventive maintenance.

Argue all you want. But ask yourself the last time you heard of somebody that got busted for taking out an instrument, sending/taking it for repair, and reinstallation of that instrument in their own airplane. Hell, 21.303 (b)(2) even gives the owner the right to MAKE parts (including instruments) for their own aircraft.

Jim
 
Sorry that was a combination of a typo and nonstandard nomenclature. I was referring to Part 43 Appendix A, the description of what a pilot can do maintenance wise on his own. The reference was supposed to be 43/A not 23/A.
FAR 43 even weaselwords this section. THe section you quote only applies (section 30) to "specifically identified as preventive maintenance in a primary category aircraft type certificate or supplemental type certificate holder's approved special inspection ... program..."
You're right about section 30...but Lance was quoting from section 31, which has no such limitation.
 
You're right about section 30...but Lance was quoting from section 31, which has no such limitation.

You are correct. I missed that in the scan. That gives you the express permission; my argument on express denial (loose construction) remains.

Jim
 
The 214 is really old and touchy. You might have some problems finding someone to work on it.


You could (and should if doing lots of IFR) replace the 214 with a KN75 & KI209 combo.

Good Luck Greg!!

The adjustment for your setup is on the 214 head.

The best way to handle it is to use a handheld GPS for navagation and just use the planes gauges to make the legal IFR filing. :)
 
Argue all you want. But ask yourself the last time you heard of somebody that got busted for taking out an instrument, sending/taking it for repair, and reinstallation of that instrument in their own airplane. Hell, 21.303 (b)(2) even gives the owner the right to MAKE parts (including instruments) for their own aircraft.

Jim


So how does an aircraft owner without an A&P certificate sign off taking out an instrument, take it in for repair and reinstall it in their own airplane without the required signoff?

§ 43.9 Content, form, and disposition of maintenance, preventive maintenance, rebuilding, and alteration records (except inspections performed in accordance with part 91, part 125, §135.411(a)(1), and §135.419 of this chapter).

(a) Maintenance record entries. Except as provided in paragraphs (b) and (c) of this section, each person who maintains, performs preventive maintenance, rebuilds, or alters an aircraft, airframe, aircraft engine, propeller, appliance, or component part shall make an entry in the maintenance record of that equipment containing the following information:
(1) A description (or reference to data acceptable to the Administrator) of work performed.
(2) The date of completion of the work performed.
(3) The name of the person performing the work if other than the person specified in paragraph (a)(4) of this section.
(4) If the work performed on the aircraft, airframe, aircraft engine, propeller, appliance, or component part has been performed satisfactorily, the signature, certificate number, and kind of certificate held by the person approving the work. The signature constitutes the approval for return to service only for the work performed.
(b) Each holder of an air carrier operating certificate or an operating certificate issued under Part 121 or 135, that is required by its approved operations specifications to provide for a continuous airworthiness maintenance program, shall make a record of the maintenance, preventive maintenance, rebuilding, and alteration, on aircraft, airframes, aircraft engines, propellers, appliances, or component parts which it operates in accordance with the applicable provisions of Part 121 or 135 of this chapter, as appropriate.
(c) This section does not apply to persons performing inspections in accordance with Part 91, 125, §135.411(a)(1), or §135.419 of this chapter.
(d) In addition to the entry required by paragraph (a) of this section, major repairs and major alterations shall be entered on a form, and the form disposed of, in the manner prescribed in appendix B, by the person performing the work.
[Amdt. 43–23, 47 FR 41085, Sept. 16, 1982, as amended by Amdt. 43–37, 66 FR 21066, Apr. 27, 2001; Amdt. 43–39, 69 FR 44863, July 27, 2004]


§ 43.13 Performance rules (general).

(a) Each person performing maintenance, alteration, or preventive maintenance on an aircraft, engine, propeller, or appliance shall use the methods, techniques, and practices prescribed in the current manufacturer's maintenance manual or Instructions for Continued Airworthiness prepared by its manufacturer, or other methods, techniques, and practices acceptable to the Administrator, except as noted in §43.16. He shall use the tools, equipment, and test apparatus necessary to assure completion of the work in accordance with accepted industry practices. If special equipment or test apparatus is recommended by the manufacturer involved, he must use that equipment or apparatus or its equivalent acceptable to the Administrator.


§ 43.3 Persons authorized to perform maintenance, preventive maintenance, rebuilding, and alterations.

(a) Except as provided in this section and §43.17, no person may maintain, rebuild, alter, or perform preventive maintenance on an aircraft, airframe, aircraft engine, propeller, appliance, or component part to which this part applies. Those items, the performance of which is a major alteration, a major repair, or preventive maintenance, are listed in appendix A.
(b) The holder of a mechanic certificate may perform maintenance, preventive maintenance, and alterations as provided in Part 65 of this chapter.







Argue all you want. But ask yourself the last time you heard of somebody that got busted for taking out an instrument, sending/taking it for repair, and reinstallation of that instrument in their own airplane. Hell, 21.303 (b)(2) even gives the owner the right to MAKE parts (including instruments) for their own aircraft.

Jim

But without an A&P certificate the owner cannot remove and replace those parts. Is that really that hard to understand?
 
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Your main premise is mis-stated in the first paragraph. The owner removes the radio for a "bench test". Repeat with emphasis, "BENCH TEST". That can be done in five minutes. But the shop does not stop there, they "realign the receiver". That is an unnecessary hour that purports to fix the problem the owner has. Now they are in fact on the hook for the repair since they did not stop at what the owner asks for. THe simple return of the radio with "bench tests OK" would have saved them a lot of grief.



Jim

Perhaps that's the way you performed "bench test". The shop I use only does the work I request then makes recommendations and leaves it up to me as to how to continue.
 
You could (and should if doing lots of IFR) replace the 214 with a KN75 & KI209 combo.

Well, given I have NEVER flown the airplane IFR, a LOT of IFR flying isn't in the cards. :smile:

The adjustment for your setup is on the 214 head.

That is what I wanted to know.

The best way to handle it is to use a handheld GPS for navagation and just use the planes gauges to make the legal IFR filing. :)

That is more or less where I am headed. :smile:
 
So how does an aircraft owner without an A&P certificate sign off taking out an instrument, take it in for repair and reinstall it in their own airplane without the required signoff?
...snip...
But without an A&P certificate the owner cannot remove and replace those parts. Is that really that hard to understand?

It is hardly necessary to quote part 43. My copy is quite dog-eared, thank you.

How does the aircraft owner take out an instrument? Quite simple. Four screws, one in each corner.

Now ask yourself .... the reg prohibits MAINTENANCE. Is removal, remanding to a certificated shop, and replacement maintenance? Yes, it is, and it is done by the shop. If you want to have the SHOP sign the log for the fixit part, go for it. However, simple removal and replacement is NOT maintenance.

And yes, you are really making it hard to understand.

Jim
 
Perhaps that's the way you performed "bench test". The shop I use only does the work I request then makes recommendations and leaves it up to me as to how to continue.

Absent instructions to the contrary, a "bench test" of a com radio is a simple receive sensitivity test, one at the low end of the band, one at the high end of the band, and one in the middle and then a transmit power test. Using an IFR-1200S I can do one in about two minutes.

A nav radio is pretty much the same thing; three VOR and two LOC tests.

Five minutes at the outside.

Jim
 
Absent instructions to the contrary, a "bench test" of a com radio is a simple receive sensitivity test, one at the low end of the band, one at the high end of the band, and one in the middle and then a transmit power test. Using an IFR-1200S I can do one in about two minutes.
That old thing? What a boat anchor! Get a real service monitor. :D

A nav radio is pretty much the same thing; three VOR and two LOC tests.
What do you use to test these? Is there an attachment you put on the service monitor, or a separate piece of gear?
 
However, simple removal and replacement is NOT maintenance.


Jim

FAR 1.1 Definitions : Maintenance means inspection, overhaul, repair, preservation, and the replacement of parts, but excludes preventive maintenance.

Thanks for proving my point you don't have an understanding of FAR's. Tell ya what Jimbo, go find an Avionics Fed and tell him that removing and reinstalling a navigation indicator is not maintenance and therefor doesn't require a part 43 maintenance entry. While you're at it tell him also that an uncertified individual can make a calibration adjustment without data or the required equipment and also doesn't require a maintenance entry.

And to give you the benefit of the doubt I made a call this morning to a friend of mine in the MCO FSDO office who use to be my PAI. I just ran the above scenarios by him and he had a good laugh. He said the FAR's a clear on the subject and any competent A&P would know that.

I'm done arguing with you on the subject. I'll follow the regs and you do whatever makes you feel good.

Have a nice day :D
 
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Glad you all got that settled.
 
I'm done arguing with you on the subject. I'll follow the regs and you do whatever makes you feel good.

Have a nice day :D

Could you be bothered to answer the question from back in post # 39?

Thank you,

Tim
 
Could you be bothered to answer the question from back in post # 39?

Thank you,

Tim

Tim,

I've never dealt with experimental aircraft so I couldn't give you the answer on that without doing some research. Perhaps someone here that does work with experimentals could answer that for you.
 
On experimentals, the owner can remove and replace. The adjustments? Dunno.
 
That old thing? What a boat anchor! Get a real service monitor. :D

What do you use to test these? Is there an attachment you put on the service monitor, or a separate piece of gear?

If you think the IFR is a boat anchor, then I suspect the Systron-Donner spectrum analyzer plug-in to the HP 141T straight out of the 1960s would qualify also.

As would the TIC that I use to do the nav checks.

But then again, what am I checking? A com system that was outmoded in the 1940s and a nav system that was obsolete in the 1950s.

Jim
 
those are great stories...


"You seek your god in rule books and idols made by men, and all the while that
god is within you. Safety is that which you know, not what somebody else thinks
it would be nice for you to comply with. Ask your FAA inspector for the
approved definition of safety. There is none. How can any agency guide toward
that which it can't even define?" (Richard Bach, "Found At Pharisee")
 
I had opportunity to check my VORs against a VOT today. One was 6 degrees off, the other was 8 degrees off. I have no intentions of flying the airplane IFR so this is not a big deal as of now. But I WANT to be able to fly it IFR. Technically, since the VORs are within 4 degrees of EACH OTHER, it is legal, but now that I KNOW they are off, there is no way.

Now for the question. How are the VOR receivers adjusted? Is it an adjustment in the head, or is it in the radio?

Also, since I am asking, my glideslope does not wake up until inside the marker. I don't have an external glideslope antenna, as far as I know. FWIW, it has worked properly in the past. I have been told the head is pretty much FUBARed but that was after a verbal discussion, not after any testing. Any ideas?

These are KX 170B's by the way.

There are two problems I typically see, the converter needs adjusting, or the physical ring wheel has slipped. Can these be adjusted? yes, can you adjust them, if you're careful and do some research? Yes. However, is that in your best interest/value? Answer is in my experience, probably not. It's probably time to send it in for an overhaul. These it seems to me are the opening symptoms to what is often a swiftly debilitating problem, and the extra in and outs and trips to the shop and failures work against doing the minimal repair. Often times the price of the overhaul is not much greater than the repair. If you want to do it to learn and tinker and a failure will cause you no great worry, go for it. It will be educational.
 
However, is that in your best interest/value? Answer is in my experience, probably not. ...If you want to do it to learn and tinker and a failure will cause you no great worry, go for it. It will be educational.

WHERE DID I EVER SAY THAT I WANTED TO DO THIS? I just wanted to know what was involved and everyone seems to think I want to do the overhaul myself.
 
WHERE DID I EVER SAY THAT I WANTED TO DO THIS? I just wanted to know what was involved and everyone seems to think I want to do the overhaul myself.

Kinda like the eyeglasses repair we did at Gaston's? :D
 
i think i can recall most of it. Tommy's glasses broke. Spike, Dave Taylor and Lance Flynn gathered behind the Viking with Dave's tool box to attempt a fix. Proper tools were tough to come by. You don't fix airplanes with eyeglass tools I guess. At some point, someone dropped one of those microscopic screws in the grass. We all figured it was hopeless but then Lance found it. So we started calling him "Eagle Eyes". I think we also got a picture of Lance simulating eyeglass repair while holding a small axe or sledgehammer or something.

I really have no idea how this relates to your radio Greg, but it was cool to watch.
 
WHERE DID I EVER SAY THAT I WANTED TO DO THIS? I just wanted to know what was involved and everyone seems to think I want to do the overhaul myself.
C'mon Greg, we know you're just dying to rip into the indicator and fix it yourself (even though you only asked where the problem was likely to be).:D
 
On experimentals, the owner can remove and replace. The adjustments? Dunno.
In a amateur built you can build your own instruments and avionics for the most part, I'm pretty certain you can adjust them.
 
WHERE DID I EVER SAY THAT I WANTED TO DO THIS? I just wanted to know what was involved and everyone seems to think I want to do the overhaul myself.

You didn't directly, though you did say:
Now for the question. How are the VOR receivers adjusted? Is it an adjustment in the head, or is it in the radio?
I assumed since you asked that of "Avionics Geeks" you might be considering doing it. I used to do my own radio repair to an extent, but I had a test bench available to me.
 

Not a bad assumption though, you're an intelligent thoughtful curious guy with enough fortitude to own a 195. It's not particularly out of line for me to think you would consider it since it's 1 of 2 and you're not IFR anyway.

Personally I would do it in your position since you don't have much to lose and upgrading the equipment wouldn't be that expensive since you don't need to go to current gen gear to get an upgrade. Besides, the minute you figure you're over your head, you can stop and send it in for overhaul and you're no worse off for the doing. OTOH, I may just actually fix it. Either way I have learned something.
 
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WHERE DID I EVER SAY THAT I WANTED TO DO THIS? I just wanted to know what was involved and everyone seems to think I want to do the overhaul myself.

BTW, my prime point was that if you're going to "repair" the head, it isn't worth it to have a shop do. If you're gonna send it to a shop, go ahead and get it overhauled completely. If you're going to try for "repair" it only makes sense if you do your own.
 
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