Swapout of Garmin MX20. Any docs required?

stevenhmiller

Pre-takeoff checklist
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Steve's Archer
My Garmin MX20 failed on me. A fellow member was gracious enough to give me his old unit for the price of shipping (thank you Brandon!)
I received only the unit, no paperwork with it. The MX20 is a tray unit, so I simply unscrewed the single screw that holds it in, slid out my old unit and slid in the replacement and tightened the screw. The replacement unit works perfectly.

Legally, do I need to get any paperwork from a certified avionics shop, or can I simply make a log entry and be done? If I need paperwork, what do I need?
 
The MX20 can be replaced with a log book entry. A more disturbing issue is without paperwork, how do you know you have an airworthy part?

(But frankly, I'd not worry about it).
 
Simply by ops checking it with the MX20 Installation Manual.

Not exactly rocket science. I compared the replacement unit to mine and they are identical. The seals are not broken, and I replaced the datacard with mine. The replacement is simply slide into existing chassis and tighten one screw. Turn on, and check functionality. All is working, as expected and communicates with my Garmin 480.
 
Not exactly rocket science. I compared the replacement unit to mine and they are identical. The seals are not broken, and I replaced the datacard with mine. The replacement is simply slide into existing chassis and tighten one screw. Turn on, and check functionality. All is working, as expected and communicates with my Garmin 480.
Sounds good, that's just a log entry swap, and more for insurance/theft issues than anything else.
 
Not exactly rocket science. I compared the replacement unit to mine and they are identical. The seals are not broken, and I replaced the datacard with mine. The replacement is simply slide into existing chassis and tighten one screw. Turn on, and check functionality. All is working, as expected and communicates with my Garmin 480.


Any airworthiness directives apply to those? (IDK) Are they a life limited part? (no)

You can sign it off similar:

Date: XX/XX/XXXX Tach Time: XXXXX Removed part #XXXXXX serial #XXXXXXX and installed servicable p/n XXXXXX s/n XXXXXXX in accordance with MX20 Installation Manual Rev XX. Joe Blow Owner/Operator Pilot Certificate # 12345678.


I’m curious if the mod status between the two are the same.

(g) Except for holders of a sport pilot certificate, the holder of a pilot certificate issued under part 61 may perform preventive maintenance on any aircraft owned or operated by that pilot which is not used under part 121, 129, or 135 of this chapter. The holder of a sport pilot certificate may perform preventive maintenance on an aircraft owned or operated by that pilot and issued a special airworthiness certificate in the light-sport category.
(c) Preventive maintenance. Preventive maintenance is limited to the following work, provided it does not involve complex assembly operations:
(31) 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, and operational check must be performed in accordance with the applicable sections of part 91 of this chapter.
 
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Not exactly rocket science. I compared the replacement unit to mine and they are identical. The seals are not broken, and I replaced the datacard with mine. The replacement is simply slide into existing chassis and tighten one screw. Turn on, and check functionality. All is working, as expected and communicates with my Garmin 480.

A lot of LRU (line replaceable units) have configuration settings in menus that have to be set properly. I'm not familiar with MX20 so I can't really say. There is a pretty big post installation setup section to the installation manual tho.
 
A lot of LRU (line replaceable units) have configuration settings in menus that have to be set properly. I'm not familiar with MX20 so I can't really say. There is a pretty big post installation setup section to the installation manual tho.

These settings are saved on the datacard. I took out the previous owners datacard and put in mine. It is using my settings now, and I have verified them.
 
Any airworthiness directives apply to those? (IDK) Are they a life limited part? (no)

You can sign it off similar:

Date: XX/XX/XXXX Tach Time: XXXXX Removed part #XXXXXX serial #XXXXXXX and installed servicable p/n XXXXXX s/n XXXXXXX in accordance with MX20 Installation Manual Rev XX. Joe Blow Owner/Operator Pilot Certificate # 12345678.


I’m curious if the mod status between the two are the same.

(g) Except for holders of a sport pilot certificate, the holder of a pilot certificate issued under part 61 may perform preventive maintenance on any aircraft owned or operated by that pilot which is not used under part 121, 129, or 135 of this chapter. The holder of a sport pilot certificate may perform preventive maintenance on an aircraft owned or operated by that pilot and issued a special airworthiness certificate in the light-sport category.
(c) Preventive maintenance. Preventive maintenance is limited to the following work, provided it does not involve complex assembly operations:
(31) 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, and operational check must be performed in accordance with the applicable sections of part 91 of this chapter.

Yes, this is what I thought. My interpretation is the same, just want to verify.
 
The MX20 can be replaced with a log book entry. A more disturbing issue is without paperwork, how do you know you have an airworthy part?
I'd be more concerned that I had a stolen part. Garmin and some others keep track of stolen avionics s/n's.

However, assuming it's OK, I believe that unit constitutes a "front instrument panel-mounted navigation device", so it sounds like preventive maintenance under item 31, requiring a log book entry, but legal for a Private Pilot to do on his/her own plane.
 
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It's not stolen. He bought it from me for a pretty unbeatable price. :)

It was serviceable when it came out of my airplane, save for a bunch of vertical lines on the screen. But it wasn't "yellow-tagged" or inspected.

I bought it with my airplane but there may be a purchase receipt somewhere in my paperwork, but I'd have to dig. More likely, there isn't and all I have are forms and logbook entries from when it was installed and removed.
 
It's not stolen. He bought it from me for a pretty unbeatable price. :)

It was serviceable when it came out of my airplane, save for a bunch of vertical lines on the screen. But it wasn't "yellow-tagged" or inspected.

I bought it with my airplane but there may be a purchase receipt somewhere in my paperwork, but I'd have to dig. More likely, there isn't and all I have are forms and logbook entries from when it was installed and removed.

I'm extremely happy with the unit, and the price can't be beat! Brandon is a stand-up guy and unselfishly helped a fellow soon-to-be pilot out. For that, I'm deeply appreciative.

As for any documents required, I've called a couple of avionics shops and did some research into the FAR. Since the unit is made to slide in and out of a tray, as-needed, and there are no alterations to wiring or the plane, it is considered regular maintenance and can be done by a pilot with just a log book entry. Nothing further is required. No yellow tags required, nothing. So, I got my CFI to verify the workings of the unit and enter the log book entry for me, since I'm not a private pilot yet. :D
 
So, I got my CFI to verify the workings of the unit and enter the log book entry for me, since I'm not a private pilot yet. :D

Hold the PHONE! CFI's are not mechanics. They have no authority to perform and log maintenance on other people's aircraft.

Actually, all YOU need to do this is a student pilot certificate, you can log it. Your CFI can not.

I never said a yellow tag was required, just the assurance that the part was airworthy. Others have suggested ways of telling and even given the pedigree of this particular part is likely sufficient.
 
Hold the PHONE! CFI's are not mechanics. They have no authority to perform and log maintenance on other people's aircraft.

Actually, all YOU need to do this is a student pilot certificate, you can log it. Your CFI can not.

I never said a yellow tag was required, just the assurance that the part was airworthy. Others have suggested ways of telling and even given the pedigree of this particular part is likely sufficient.

My interpretation is that a person with a minimum of a Private Pilot License can sign off on the unit in the log book. I'm still just a student pilot. My CFI is also an A&P (I never mentioned that part), so I believe I"m covered.
 
If he is an A&P he is covered. But a pilot can only sign off aircraft he owns or operates. (I guess you can consider your CFI to be an operator for some flight, but in the broad sense he can't).

But your interpretation is WRONG.

Here's the reg:
Except for holders of a sport pilot certificate, the holder of a pilot certificate issued under part 61 may perform preventive maintenance on any aircraft owned or operated by that pilot which is not used under part 121, 129, or 135 of this chapter. The holder of a sport pilot certificate may perform preventive maintenance on an aircraft owned or operated by that pilot and issued a special airworthiness certificate in the light-sport category.

If they wanted to exclude student pilots or limit it to private or better, they would have said that. A student pilot certificate IS a pilot certificate that is issued under part 61. It is what gives you the authority to be pilot in command when solo.
 
I believe the student "certificate" says license on it. Or at least it did. So it may not be or qualify as a certificate.
 
Hold the PHONE! CFI's are not mechanics. They have no authority to perform and log maintenance on other people's aircraft.

I'm not so sure. "...the holder of a pilot certificate issued under part 61 may perform preventive maintenance on any aircraft owned or operated by that pilot..."


Actually, all YOU need to do this is a student pilot certificate, you can log it.

I agree with that. See post 22
 
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Knew I should have looked here first :mad2:

§43.7 Persons authorized to approve aircraft, airframes, aircraft engines, propellers, appliances, or component parts for return to service after maintenance, preventive maintenance, rebuilding, or alteration.


(f) A person holding at least a private pilot certificate may approve an aircraft for return to service after performing preventive maintenance under the provisions of §43.3(g).


While part 91 doesn't require you to hold at least a private, part 43 does.
 
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My quote DOES come from part 43. The operative difference is the "return to service" part.
 
Hold the PHONE! CFI's are not mechanics. They have no authority to perform and log maintenance on other people's aircraft.

Actually, all YOU need to do this is a student pilot certificate, you can log it. Your CFI can not.

I never said a yellow tag was required, just the assurance that the part was airworthy. Others have suggested ways of telling and even given the pedigree of this particular part is likely sufficient.

It doesn't have to be the owner.
 
Steve I'm curious how bad or good the screen looked when you fired it up. Were the lines still present or did the time in the box in my garage make them disappear? :D
 
Steve I'm curious how bad or good the screen looked when you fired it up. Were the lines still present or did the time in the box in my garage make them disappear? :D

Brandon, I hadn't seen any lines. I only powered it up in the hangar for a short check. I'm going up in the morning and will see how it behaves over a 2 hour haul.
 
Steve I'm curious how bad or good the screen looked when you fired it up. Were the lines still present or did the time in the box in my garage make them disappear? :D

Flew a couple of hours today and all was good. No lines on the screen at all. happy camper! :D
 
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