Experimental G5 install in lieu of Certified one

Dan Gordon

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I'm just checking to see if its possible to intall the experimental G5 unit in a certified (legacy) plane? I want to install (2) in my plane to eliminate the vacuum system. I'm wondering if I can buy the less expensive experimental units, using the following document:

https://www.seaerospace.com/documents/FAA_vacuum_replacement.pdf

Just trying to save a few $$'s...thoughts? Is there a way this can be done? Besides the STC, is there any difference between the experimental and certified G5?
 
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The experimental units do not have an STC. How do you propose to do this without it?
 
The experimental units do not have an STC. How do you propose to do this without it?
Work with the A&P at my local airport. See if he can sign off on the install.
 
if its possible to intall the experimental G5 unit in a certified (legacy) plane?
Yes. But first there is no such thing as an "experimental" part. However, if you want to use the Policy memo you reference to pursue a the G5 install as a minor alteration to replace the vacuum system you get into a gray area with the non-approved G5 version. But its still doable. I recommend sitting down with your mechanic and work both scenarios: approved G5 with PCE letter, and non-approved G5 with field approval. Work out your cost differences. In most cases I've seen the certified route be most cost efficient. Plan B could be you install a cert G5 to remove vac system then install your second non-approve G5 as a minor alteration to get your "additional" functions. Without more info can't add much more.

The experimental units do not have an STC. How do you propose to do this without it?
FYI: STCs have several uses and are not the only option in a number of cases.
 
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Need STC units to replace primary instruments. G5’s are not TSO approved, and used the STC process to gain production approval for installation in standard aircraft.
 
Same question, but you have 2 certified G5s, no vacuum system and want to add another G5, but uncertified, on the copilot's side as a backup. I know the DG G5 can be turned into a AI, but if you also use the DG as an indicator you give up a lot when you do that, say in hard IFR.
 
want to add another G5, but uncertified, on the copilot's side as a backup.
Yes. So long as you cover the minimum equipment requirements for the intended ops you can install anything you want. You can install 3 more non-approved G5s to add to your capabilities so long as the FAR requirements are met. Anytime you alter the aircraft you have to start at square one and work forward. If that makes sense.

STC process to gain production approval for installation in standard aircraft.
FYI: STCs are not production approvals. Only design approvals with a number of guidance docs on this subject. I don't believe there is a TSOA for a G5 type instrument but I could be wrong. Given Part 21 requires certain minimums for a vendor to sell parts for TC'd aircraft a number of vendors use an AML-STC type approval to cut costs and offer those same parts across many aircraft models. Theres no requirement to use that STC as long as you meet the Part 43 alteration requirements. However, since the PCE memo above allows the swap of a G5 or an RC Allen indicator, etc. for a vacuum indicator as a minor alteration (not a major alteration) it "implies" you are using the STC certified version of the G5 or whatever. But the memo does not explicitly state the indicator must be "approved." Hence the gray area. Its all in the installation approval, ie. design approval side.
 
I believe software is going to be your stickiness of wicketdom.
 
G5’s were approved via the new part 23 consensus standards. STC approval allowed method for FAA approved production for standard category aircraft.
 
My Light Sport came with the experimental G5 installed at the factory. I enjoy the flexibility, with a twist of a knob my attitude indicator becomes an HSI.
 
I have replaced the vacuum system with two G5s ,never considered the experimental units. I would guess your trying to save some cash on the upgrade.
 
I have replaced the vacuum system with two G5s ,never considered the experimental units. I would guess your trying to save some cash on the upgrade.
Yes, always looking to save a bit of money where I can.
 
The common comment is that exp glass instruments can be installed for entertainment but primary instruments must remain in place. If there was a legal path to use exp Garmin wouldn’t produce two versions of the same instrument.
 
G5’s were approved via the new part 23 consensus standards. STC approval allowed method for FAA approved production for standard category aircraft.
FYI: you may want to check your references. Part 23 and its associated consensus standards only apply to complete airplanes and result in a type certificate approval. The G5 falls under the definition of an article and are approved under Part 21 which covers STCs, PMA, TSOs, etc. Part 21 also covers production approvals which is required to manufacture a part for sale. I believe Garmin has a separate production certificate (PC) to handle that end of their business.

If there was a legal path to use exp Garmin wouldn’t produce two versions of the same instrument.
Not necessarily. Its my understanding all G5s, etc. that offer two versions are made on the same line. At the end the ones to go certified get a different data tag and may have some of the software deactivated. But with some equipment they leave the non-cert software active and only state in the install manuals which functions fall under the TSO, PMA, etc. It depends on OEM.
 
There is no design approval for the G5 under part 21. STC Approval based an current part 23 requirements limited to airplanes under 6000 lbs gross weight with a maximum of 6 approved seats...
 
There is no design approval for the G5 under part 21.
Curious. If the G5 design approval, ie. STC, is not issued under Part 21 Subpart E, can you provide the specific Part 23 section/paragraph that does? You may want to review Order 8110.4 or AC 21.40 for possible references.
 
Clarification: there is no separate part 21 design certification for the G5. The article is approved for installation via STC.
 
https://shop.levil.com/

Met these folks on their way back from OSH.

Dunno if the price/functionality would work for you but was a really interesting concept.
 
Curious. If the G5 design approval, ie. STC, is not issued under Part 21 Subpart E, can you provide the specific Part 23 section/paragraph that does? You may want to review Order 8110.4 or AC 21.40 for possible references.

IDK if its still true but the "experimental" versions (as stated in the retailer's websites) came with a PMA sticker on them and the LRU part number matched the STC installation manual. The STC kits (as stated in the retailer's websites) come with the STC LOA and identical LRU part number and PMA sticker as the kits sold as experimental . There was no difference in the physical LRUs. The STC install manual breadcrumbs to the STC software downloading portal not the experimental software downloading portal.

https://vansairforce.net/community/showthread.php?t=153405
 
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I have wondered the same thing.
For half the cost for the exact same part number it's hard to swallow.

How is the STC handled, is it connected to a serial number or is it a blanket STC?
 
I have wondered the same thing.
For half the cost for the exact same part number it's hard to swallow.

How is the STC handled, is it connected to a serial number or is it a blanket STC?
I have the same question, if the unit is no different, it’s a bitter pill to swallow.
 
I have the same question, if the unit is no different, it’s a bitter pill to swallow.
To be fair they are all this way, Garmin, Dynon, Etc certified always costs way more even though it's the same part. Makes sense because there's a lot of testing and R&D involved in the approval process for certified parts.
that being said If I can avoid giving a few more dollars to Garmin by finding a loophole I'm A-OK with that :D.
 
I have wondered the same thing.
For half the cost for the exact same part number it's hard to swallow.

How is the STC handled, is it connected to a serial number or is it a blanket STC?

This STC package is entirely available online for free, the "licensing agreement" to use it on your airplane is not. I would not buy a certified airplane equipped with G5s without verifying this Letter of Authorization (licensing agreement) is in the aircraft records and is valid and all G5 equipment installed matches STC part numbers and contain the Garmin FAA/PMA data tags.

Additionally, if someone was selling a used one, and the data tag was intact, matched the STC part number 011-03809-00, and contained the FAA/PMA markings, I would consider it eligible for use on certified aircraft.
 
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IDK if its still true but the "experimental" versions (as stated in the retailer's websites) came with a PMA sticker on them and the LRU part number matched the STC installation manual.
I don’t recall seeing items with a PMA stamp but have seen that with TSO items. The units would come down the same production line where some would get a TSO data tag and some get plain tag. A PMA approval is usually a standalone approval for design/production/installation where the TSO is not an install approval and needs something else like a STC to install if a major alteration.

In the past, a vendor would generally obtain a standard or multiple STC for the design/install approval then use a TSO, PMA, or PC for production approval. However, there are only so many TSOAs and they don’t cover every type of equipment. So with some of the new digital units out there where is no applicable TSOA they are using the STC for design/install approval and a PC for production. No TSO or PMA. But keep in mind the only reason vendors use the “experimental” tag is not to bust FAR 3. Same with the FAA NORSEE approval mentioned in a separate thread. Vendors have to play by different rules than installers.
How is the STC handled, is it connected to a serial number or is it a blanket STC?
To add to the above, in order to use someone's STC you need to obtain a permission letter by aircraft S/N from the STC holder (91.403(d). But there is no rule that prevents you from obtaining your own approval to install a G5.
 
To add to the above, in order to use someone's STC you need to obtain a permission letter by aircraft S/N from the STC holder (91.403(d). But there is no rule that prevents you from obtaining your own approval to install a G5.

Thanks, can you elaborate? do you mean a field approval?
 
Thanks, can you elaborate? do you mean a field approval?
Possibly a field approval. Maybe even a One-Only STC. I haven't really looked into it. However, if you want to tempt fate I would get your ducks in a row with your mechanic and IA and see if you could try it as a minor alteration. With the shift in FAA procedures with the current policy letters out there on equipment replacements why not discuss with your local FSDO. The policy letter listed in the OP doesn't differentiate in the part approval only that a G5 or similar type can be installed as a minor in certain aircraft. It would be something to at least pursue until you get a definite NO. However, I would start with your APIA first as they're usually the ones who prefer not to rock the boat for obvious reasons.
 
I have certified G5s in my 172. To download the STC, you first have to enter the code from the Letter of Authority and then print that letter for your log book. The difference between the 2 units is probably around 1 AMU and quite honestly, for that amount, I wouldn't chance the paperwork **** show that's going to happen when you try to get FSDO approval on a 337.

Flying ain't cheap. Don't trust your life to something uncertified in a bird that could be used in an IFR environment. If you're VFR only then consider the AV30s for around $2k each, possibly less online or on eBay.
 
Would it work? More than likely
Would it be legal? No
Would a mechanic sign off on the install, would a future mechanic reviewing log book for an annual or pre buy approve? No
Would I do it? No
 
When you install a certified G5, the STC permission letter is sent to you after you register with Garmin. It has your name, aircraft type, n number and serial number printed on it.
 
I have certified G5s in my 172. To download the STC, you first have to enter the code from the Letter of Authority and then print that letter for your log book. The difference between the 2 units is probably around 1 AMU and quite honestly, for that amount, I wouldn't chance the paperwork **** show that's going to happen when you try to get FSDO approval on a 337.

Flying ain't cheap. Don't trust your life to something uncertified in a bird that could be used in an IFR environment. If you're VFR only then consider the AV30s for around $2k each, possibly less online or on eBay.
Are EAB aircraft not allowed to operate under IFR? Or are you saying it’s not safe to fly an experimental in instrument conditions if the equipment was sold for experimental use only?
 
Me: if non-revenue IMC behind the "exp" PFD is safe for EAB, why isn't it for fac-built?

FAA:
ashlee-simpson-hoedown.gif
 
I know from past experience that when an E-AB plane crashes, the FAA does not seek accountability like when a certified aircraft crashes. I agree that if there is no real difference in avionics manufactured except a sticker, the price should not be different...but when you factor in liability, that starts to make a difference.
 
but when you factor in liability, that starts to make a difference.
FYI: Its actually a bit more than just liability and has more to do with international convention. The bulk of the FARs get their core requirements from ICAO and other agreements the US is a signatory. The benefit is that aircraft/airmen from each member country can operate within each other members airspace/industry with no further requirements in most cases. However, each country can make other rules for aircraft/airmen within their sovereign airspace. For example, Canada allows Owner-Maintained certified aircraft which cannot operate or be exported outside Canada because they no longer meet the ICAO requirements. Another example is the policy memo above allowing replacement of the vacuum system with electric alternatives as a minor alteration. This too doesn't exactly follow ICAO standards but with the EASA now accepting the G5 and other non-approved equipment for install I suspect the ICAO standards will be tweaked to allow this as well. There's more to this but in general this is the main reason for additional requirements found on the type certificated side of things.
 
FYI: Its actually a bit more than just liability and has more to do with international convention. The bulk of the FARs get their core requirements from ICAO and other agreements the US is a signatory. The benefit is that aircraft/airmen from each member country can operate within each other members airspace/industry with no further requirements in most cases. However, each country can make other rules for aircraft/airmen within their sovereign airspace. For example, Canada allows Owner-Maintained certified aircraft which cannot operate or be exported outside Canada because they no longer meet the ICAO requirements. Another example is the policy memo above allowing replacement of the vacuum system with electric alternatives as a minor alteration. This too doesn't exactly follow ICAO standards but with the EASA now accepting the G5 and other non-approved equipment for install I suspect the ICAO standards will be tweaked to allow this as well. There's more to this but in general this is the main reason for additional requirements found on the type certificated side of things.

I thought the FARS existed before ICAO did.
 
I thought the FARS existed before ICAO did.
The CARs existed as well as the UK BCARs and the French DGAC CAC rules. However, in the mid-1940s when a number of countries signed on to the Chicago Convention and created the ICAO they basically took those 3 rule sets and developed the basis of the ICAO rules of today. When we transitioned from the CARs to the FARs there were a number of revisions to the rules to be more inline with the ICAO standards.
 
To be fair they are all this way, Garmin, Dynon, Etc certified always costs way more even though it's the same part. Makes sense because there's a lot of testing and R&D involved in the approval process for certified parts.
that being said If I can avoid giving a few more dollars to Garmin by finding a loophole I'm A-OK with that :D.
Actually, the Dynon equipment costs the same whether certified or experimental. With the Dynon, you pay a 1-time $2,000 STC fee per airplane for permission to use the STC. All of the equipment is the exact same price as the experimental. With a Garmin system, each component has its own STC fee built in, making the whole system substantially more expensive.
 
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