hish747
Pre-takeoff checklist
Is a 337 required to install an Apollo GX60 GPS/Com for VFR use?
Thank you,
Hish747
Thank you,
Hish747
337 Required for VFR GPS installation?
- Thread starter hish747
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bnt83
Final Approach
You're going to get a lot of opinions but in this case I'd let you decide.
hish747
Pre-takeoff checklist
It might not make a difference but I should say that I'm replacing an Apollo 618 Loran which has a top mounted antenna. The Apollo GX is a slide in replacement and pin compatible with the 618 Loran. The Loran antenna will be swapped out for a GPS antenna but the tray and antenna connectors are staying the same.
AKBill
En-Route
No, it's not a major repair or major alteration. As stated above logbook sign off from the installer
mtuomi
En-Route
The "GPS AC" says VFR installation is a logbook entry, IFR needs the 337/STC process.
I recently installed a GX50. We did the initial VFR-only install as a minor alteration, logbook entry only. My installer (A&P/IA) was comfortable that it was a minor alteration so long as we added the "GPS FOR VFR ONLY USE" placard on the panel. I did have a compatible pre-existing antenna on the airplane, but he wouldn't have had an issue installing a new one as a minor alteration since my airplane isn't pressurized. The most relevant FAA guidance on this issue is AC 20-138D. For VFR-only installs, look at Appendix 6. It certainly insinuates that it's a minor alteration (though that decision is ultimately the installers). I then went through the field approval process to get my unit approved for IFR use. If you need some guidance on that, please let me know as it's all still very fresh.
I would like to hear more about the field approval. I'm considering going that route myself someday.
Assuming the initial install is done in accordance with the IFR requirements in the installation manual, the field approval is nothing more than a paperwork exercise. It's a bit of a pain in the ass though. I didn't use a radio shop, but just my regular A&P/IA, and I think this was a little outside his wheelhouse. I did the initial install myself, under his supervision. And I prepared the initial 337 and AFMS myself, using a form provided by someone who did a similar install a couple years ago. My FSDO did not like the wording on the 337 and wanted a bunch of revisions to the AFMS. Those revision rounds took awhile, but eventually got done. I'm happy to provide a copy of the 337 as a template, it's pretty thorough at this point.
Remember, for an IFR install you have to have an interface with your altitude encoder (which has to have RS232 output). You also have to have an external CDI and various annunciators. In my case, I have an external CDI that has the annunciators built into it, so it made the install rather simple. You also have to complete a flight test in accordance with AC 20-138D (a bit of a formality, but it has to be done).
That's awesome. I'd love to get a copy of that 337. I may never do this, but one of my many possible plans is exactly what you just described. Installing the GPS myself with IA help, and then potentially doing 337 later for IFR certification. I'm guessing it's more difficult than I'm imagining though to do a compliant IFR install.
Honestly, it's really not hard. I'm not a mechanic, nor do I have any "special" training. I am reasonably handy, have a decent understanding of electronics/computers/wiring and I can read/follow an installation manual. I probably spent 2 hours planning and building the wiring harness on my desk at home. Probably another 3-4 hours doing the physical install in the airplane. The only "advantage" I had is that when I had a new encoder installed the tech pre-wired the RS232 output for me, so all I had to do was drop those 2 pins into the connector. While I had a pre-existing antenna on the airplane, I ended up having to swap it out anyway. Don't let the project intimidate you, it's well-within the capability of most people who do owner-assisted maintenance.
Total cost to get an IFR-certified GPS in my airplane:
GX-50 GPS, with tray, antenna and indicator - $900 (ebay)
New encoder, with install labot - $600
Misc. supplies (wiring, pins, crimping tool, etc.) - $250
A&P labor (supervision, 337, etc.) - $240 (4 hours)
Total: $1,990
It's not a WAAS GPS, but it's approach certified and I can file /g. Perfect for my needs, and far, far cheaper than a 430W.
I did an IA assisted G5 install, which included putting in an antenna, so I've already done a lot of the same type of work. I didn't have to integrate to an encoder though, which I'm totally ignorant about. If I bother with it though, I'd probably go with at least a 430 if not better, which might be more challenging, and certainly more costly.
If you do a 430W, you probably won't need a field approval as it's STCd for most airplanes via an approved model list. In that case, you do the install, prepare a 337 referencing the STC/AML as approved data, your IA signs and submits to OK City; no FSDO involvement at all. However, the non-WAAS 430 does need a field approval, as it was never STCd via the AML process.
The install itself will be more labor for sure, but if you can install a G5, you can do the 430 install. The toughest part will be dealing with interfacing the radio portion of the 430 to the audio panel and the necessary shielded wires. That adds a good deal more complexity to the install and the labor, in part because most of that work has to be done under the panel in the plane. Add to that the fact that I hate dealing with shielded wires, mostly due to my own inexperience. The encoder will require a radio shop for certification, though. And you have to make sure you buy an encoder with RS232 out (many older, or cheaper, units don't have this); I recommend the TransCal unit. Or, you can get a newer Garmin transponder with the encoder built-in that you can pull RS232 from.
mtuomi
En-Route
If you don't care about approaches, find a GX55, that way there's no need to worry about the encoder. CDI + "lamp annunciators", antenna and paperwork for IFR.
The AFMS you can download from Garmin is almost complete, and you can use the STC for the Partenavia as "previously accepted data" or whatever the IA term for that is.
We used Garmin's AFMS, just had to have some tweaking to make the FSDO happy. We also used the Partenavia STC as "acceptable" data (don't call it "Approved" data on the 337 or the FSDO will somewhat condescendingly point out that it's not "approved" data, and if it was, you wouldn't need the field approval). Honestly, the encoder was $600 well spent between labor and the part to get me GPS approach capability. All things considered, I think doing a GX55 just to avoid dealing with an encoder is short-sighted, but YMMV.
sfcmatta47
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Hi,
I have a GX 50 that I will like to get a certified. can you please provide me with a copy of the 337? thanks in advance.
PM me your email address, I'll happily send to you.
Hello.
Would you please share your 337 for Apollo gx50 installation?
Thanks
Jody Bryant
Niteflyer@prodigy.net
Would you please share your 337 for Apollo gx50 installation?
Thanks
Jody Bryant
Niteflyer@prodigy.net
Tom-D
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This is what takes to gain approval
Standardized Procedures for Obtaining Approval of Data Used in the Performance of Major Repairs and Major Alterations - Change 1
rotormatic1
Pre-takeoff checklist
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Rotormatic1
From FAA order 8300.16A:
g. Conditions to Consider an Alteration Minor. If all of the following conditions are met, an AFMS/RFMS is not required. For certain systems such as Global Navigation Satellite System (GNSS) for visual flight rules (VFR) use only, the alteration may be considered minor and FAA Form 337 is not required:
(1) Does not restrict, displace, or limit the use of required equipment;
(2) All new limitations can be addressed via placards;
(3) The aircraft performance is not negatively affected;
(4) Does not require a placard per TC or STC;
(5) VFR use only; and
(6) Is nonrequired equipment (refer to AC 20-138, Airworthiness Approval of Positioning and Navigation Systems).
g. Conditions to Consider an Alteration Minor. If all of the following conditions are met, an AFMS/RFMS is not required. For certain systems such as Global Navigation Satellite System (GNSS) for visual flight rules (VFR) use only, the alteration may be considered minor and FAA Form 337 is not required:
(1) Does not restrict, displace, or limit the use of required equipment;
(2) All new limitations can be addressed via placards;
(3) The aircraft performance is not negatively affected;
(4) Does not require a placard per TC or STC;
(5) VFR use only; and
(6) Is nonrequired equipment (refer to AC 20-138, Airworthiness Approval of Positioning and Navigation Systems).
rotormatic1
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Rotormatic1
Good examples would be an aircraft limited to VFR operation, or installing the unit and limiting the use of the GPS to VFR operations only.
mike Caperton
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Hey, I’m new to this forum and am in process of installing Garmin GNS 430 and 530. Any helpful information on FAA approval and a copy of the form 337 information discussed would be extremely helpful. Thank you
Mike
Mike
FYI: if you are already in the process of installing the equipment you may want to put a work stoppage in effect until you finalize your approval method and documentation. You could be setting yourself up for some unanticipated changes to your current install plan.
mike Caperton
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In process for me is reading the books and organizing, haven’t stated with stack. Is there an outline of procedures and sample letter/form I could access? Any help appreciated
Mike
Mike
Is this a TC'd aircraft or E/AB aircraft?
mike Caperton
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Also I believe best to change my posted name to idontknowanything; best way to accomplish without embarrassment? (I note few appear to use their real name on threads). Thank you
mike Caperton
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TC
The place to start your quest is with the A&P mechanic or shop that you will use to install the 430 and 530. It will be their determination which FAA approval method will be needed and what documentation will be needed for the installation. Now if you want to get a general idea of what the mechanic or shop will be using for that determination there are a number of references that may help. Unfortunately, there are too many variables in aircraft and installations to give you a singular reference to read. A few examples of these variables would be specific aircraft model, IFR or VFR installation, new or used equipment, using your APIA or a shop, and so on. The more info you provide the more able we can give a better reference to review.
mike Caperton
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Cessna 182 E model (1962), IFR or VFR (undecided, currently have 430 IFR installed), used equipment, using local AP and IA. If need additional information, you ask and I’ll provide.
This comment is more generic and not specific to a GPS install.
Even though FEDERAL is included in the term FAA their policies and interpretations are anything but uniform. Variations by FSDO, era and even individual persons are the result.
Suppose you flew 50 miles and had the install done in the neighboring FSDO’s turf.
Their policy is log entry only. At your next Annual your IA states that you needed a 337. I’ve had folks argue the point and I offer the TSDO phone number to them.
Often they want me to argue the method; on my time.
It's always easier for the IA involved in the original install to do the 337 rather than
someone at subsequent Annuals or Prebuys.
Even though FEDERAL is included in the term FAA their policies and interpretations are anything but uniform. Variations by FSDO, era and even individual persons are the result.
Suppose you flew 50 miles and had the install done in the neighboring FSDO’s turf.
Their policy is log entry only. At your next Annual your IA states that you needed a 337. I’ve had folks argue the point and I offer the TSDO phone number to them.
Often they want me to argue the method; on my time.
It's always easier for the IA involved in the original install to do the 337 rather than
someone at subsequent Annuals or Prebuys.
Checkout_my_Six
Touchdown! Greaser!
Okay. Whether you go VFR or IFR should be decided now as it will have the biggest effect on the installation requirements, approvals, and documentation. Your best reference at this point is to sit down with your APIA now, get a basic plan down on paper to include what documents/approvals he plans to use for your used equipment installation, and ask your questions to him first. If you still want more info on the specific methods he is using we can then give you the specific additional references to further your understanding. Short of those specifics I would just be guessing as to what references you need and could mistakenly send you down the wrong path. Make sense?
mike Caperton
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Thank you, any additional thoughts would be greatly appreciated. I get a lot of questions in my profession also, most of which I can’t answer because I can’t give advice. It’s difficult to fully set forth procedures when variables redirect the direction of flow associated with a project. I am familiar with AC 43-210A Chg 1 (familiar doesn’t mean working knowledge thereof). Any additional ACs or guidelines providing necessary or helpful information appreciated. I appreciate your time.
Mike
Mike
mike Caperton
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Yes makes sense. Thank you