337 required, or not?

fiveoboy01

fiveoboy01

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My airplane had a MAC 1700 nav/com. It went TU so the avionics shop installed a GNC255A.

The logbook entry says "this is considered a minor alteration" and there's no 337.

Is this correct? I don't pretend to know anything about this modification stuff at all... but I'm having a discussion and everyone is telling me that's not a minor alteration and there should have been a 337 filed.
 
Installer makes call on major vs minor alteration. Since new navcom replaces existing navcom, I suspect no change in w&b or sunstantial change to electrical system so I wouldn't expect it's a major alteration. Too many needless 337s are executed just because. I wouldn't sweat it.
 
Did it fit the same slide in tray with no alterations? I'm not familiar with those two units.
 
They put it in the same spot as the old radio.... Dimensions aren't identical though.
 
Logbook says it isn't so who is this "everybody" who's telling you it is and why do you care?
 
BillTIZ said:
Did it fit the same slide in tray with no alterations? I'm not familiar with those two units.
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Undoubtedly it did not but if it fit in the same tray then it wouldn't have been any type of alteration and the owner himself could have installed it. It's item 31 of what owner/operators are allowed to do:
Removing and replacing self-contained, front instrument panel-mounted navigation and communication devices that employ tray-mounted connectors that connect the unit when the unit is installed into the instrument panel, (excluding automatic flight control systems, transponders, and microwave frequency distance measuring equipment (DME). The approved unit must be designed to be readily and repeatedly removed and replaced, and pertinent instructions must be provided. Prior to the unit's intended use, an operational check must be performed in accordance with the applicable sections of part 91.
 
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Silvaire said:
Logbook says it isn't so who is this "everybody" who's telling you it is and why do you care?
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Just because the installer says it's right doesn't mean that it is. I'm just doing my due diligence to make sure the paperwork is in order. And my natural curiosity about how these things work also falls into play.

Undoubtedly the new radio didn't fit in the same tray and a new harness was built so it couldn't fall under preventive maintenance... The remaining question would be whether it falls under the definition of major alteration as defined by the FARs. Reading that definition, I think it can be easily argued that a nav/com swap is a minor alteration.
 
The new radio is TSO certified. IF your plane is certified to carry a NAV/COM (just because you had one doesn't mean it was approved) then the replacement of an existing (approved) piece of equipment with another approved unit is most certainly a minor alteration.
 
Cruiser said:
The new radio is TSO certified. IF your plane is certified to carry a NAV/COM (just because you had one doesn't mean it was approved) then the replacement of an existing (approved) piece of equipment with another approved unit is most certainly a minor alteration.
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The Mac he replaced wasn't TSO certified, nor is there a requirement that a NavCom be certified by the FAA.

Paul
 
PaulMillner said:
The Mac he replaced wasn't TSO certified, nor is there a requirement that a NavCom be certified by the FAA.

Paul
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TSO or not depends on the FAR operated under. Under Part 91, no TSO required for nav/com. Parts 121 or 135 have more stringent requirements. Even a headset needs to meet TSO for Part 121.
 
Not a major alteration if it used the existing mounting rails for the new tray, which he almost certainly did. Really, how does this come up in conversation, and why does anyone you're talking to care ? Sounds like people with not enough to do.
 
Every one will know if it was a major or minor at the next annual when the IA takes a look.
 
fiveoboy01 said:
Just because the installer says it's right doesn't mean that it is...
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Actually, yes it does. The signature is there, it's done. Unless you feel compelled to open some sort of investigation or feel that some sort of criminal act has been committed I'm not sure just exactly what you're looking for here.
 
Every one here knows that anything changed is a big deal. I'd venture if you asked what snuff as better, the thread will go 3-4 pages of passing a medical.
 
Silvaire said:
Actually, yes it does.
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Complete and utter BS, unless you are saying something other than every installation is done legally and with the proper paperwork, because the installer said they did it that way.

Unless you feel compelled to open some sort of investigation or feel that some sort of criminal act has been committed I'm not sure just exactly what you're looking for here.
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What a stupid statement. Don't put words in my mouth, that's not what i'm looking for at all. It was a question looking for clarification.
 
The avionics shop that installed the navcom isn't the IA that did my annual 3 weeks ago.

Anyways, I don't really care anymore, I didn't think a simple question would be so difficult to get a straight answer to.
 
fiveoboy01 said:
The avionics shop that installed the navcom isn't the IA that did my annual 3 weeks ago.

Anyways, I don't really care anymore, I didn't think a simple question would be so difficult to get a straight answer to.
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What's complicated about the installing mechanic having the authority to decide what is or is not a major alteration? People can second guess to their heart's content but the installing A&P signature in the logbook is the only "opinion" that counts. The rules are deliberately vague to allow an A&P to exercise some judgement, and anytime judgement is involved there will be arguments over whose judgement is better.
 
Witmo said:
What's complicated about the installing mechanic having the authority to decide what is or is not a major alteration? People can second guess to their heart's content but the installing A&P signature in the logbook is the only "opinion" that counts. The rules are deliberately vague to allow an A&P to exercise some judgement, and anytime judgement is involved there will be arguments over whose judgement is better.
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If the installer is allowed to use their interpretation of what constitutes a minor/major alteration, fine, that's no problem. Maybe I missed it but I didn't see anyone say that prior to you.

Edit - you did, in post #2. Ha!

I just want things to be in order with the airplane. I've already had pretty bad luck with it, having to do a major less than 100 hours after buying it, and I'm trying to do whatever I can to keep everything right... I'm not on a witch hunt to get the installer in trouble.
 
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fiveoboy01 said:
Complete and utter BS, unless you are saying something other than every installation is done legally and with the proper paperwork, because the installer said they did it that way.

What a stupid statement. Don't put words in my mouth, that's not what i'm looking for at all. It was a question looking for clarification.
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If you want to make it "illegal" I'm sure that if you dig and ask around enough you'll find someone to support you on that. I'm simply telling you you're making a big deal out of nothing, looking for an answer to a problem that doesn't exist. No BS and not stupid.
 
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