IFR avionics TSO for homebuilts

[Bede]

Does a homebuilt flying IFR require TSO'd GPS and other avionics?

I'm leaning to yes, but I can't find a CARs reference. On the other hand, nothing on an amateur built needs to be TSO'd, so why would avionics?

Any answers and associated regulatory reference appreciated.

[photofly]

Does a homebuilt flying IFR require TSO'd GPS and other avionics?

I'm leaning to yes, but I can't find a CARs reference. On the other hand, nothing on an amateur built needs to be TSO'd, so why would avionics?

Any answers and associated regulatory reference appreciated.

Installation of new parts rules (571.07):

571.07 (1) No person shall install a new part on an aeronautical product unless the part meets the standards of airworthiness applicable to the installation of new parts and, subject to subsections (2) and (3), has been certified under Subpart 61.

and:

(2) No certification referred to in subsection (1) is required where
....
(d) a new part is installed on an aircraft that is operated under a special certificate of airworthiness in the owner-maintenance or amateur-built classification; or

Therefore your parts don't need certification, but they do need to meet the applicable standards of airworthiness. What are the applicable standards of airworthiness? Refer to Standard 571.27:

The standards of airworthiness applicable to the installation of new parts are as follows:
(a) The requirements detailed in section 571.13 of this standard are met;

What does Standard 571.13 say? It says

Pursuant to section 571.13 of the CARs and subject to sections 571.07, 571.08, and 571.09 of the CARs, the following standards of airworthiness are applicable to the installation of a part:

(a) except in the case of aircraft that are operated pursuant to a special certificate of airworthiness in the owner-maintenance or amateur-built classification, only parts that are specified in the type design of an aeronautical product, or that are approved alternative parts, are eligible for installation in that product;

(b) where a type certificate holder assigns a proprietary number during the design phase to a standard or commercial part, and the proprietary part number is the only part number shown in the parts catalogue or similar document, only a part bearing the type certificate holder’s proprietary number, or an approved alternative part, shall be installed;

(c) substitution of equivalent standard or commercial parts is permitted only when the substitution does not constitute a major modification in accordance with section 571.06 of the CARs. Substantiation requires that the characteristics of the substituted part meet, or exceed, all of the requirements of the type design of the part being replaced. Reliance on substitution guides alone is not considered adequate. The evaluation of the characteristics of that part is subject to a review of specific type certificate holder’s data such as technical drawings, specification sheets, or substantiation reports associated with that type design;

(d) the part to be installed must be correctly configured for the installation in the aeronautical product; and

(e) prior to installation, the part should be inspected to ensure that it corresponds with its documentation, there are no signs of obvious damage, corrosion or deterioration, and the shelf life, where applicable, has not been exceeded.

Fabulous. (a) doesn't apply to you, (b) is not relevant, (c) doesn't apply, so you only have to comply with (d) and (e).

You also have to comply with regulation 571.13, but that doesn't seem onerous.

Now - you're talking about a GPS: if you want to use a GPS for approaches, then yes, it does have to comply with FAA TSO-C129a, TSO-C145a or TSO-C146a, or later accepted revisions as described in PL 551-003 (https://tc.canada.ca/en/aviation/refere ... etter-pl-1) You can't build your own GPS receiver and use it for approaches. For regular VFR navigation though, fill your boots.

As a general approach, I would say that you can install whatever you like on an amateur-built aircraft, but if the installation is intended to meet some regulatory requirement (like an ELT for example, or possibly a radio transmitter) then equipment without the right certification won't meet the regulatory requirement.

[photofly]

Also, I found this, which seems remarkably on-point:

Airworthiness Evaluation of the Installation of IFR Equipment
to Allow the Removal of the “VFR Only” Operating Condition
from the Special Certificate of Airworthiness – Amateur-Built

https://www.md-ra.com/docs/SI_500-024.pdf

And that document includes this bit....

(1) An application for the removal of the “VFR Only” operating condition of a Special Certificate of
Airworthiness – Amateur-built shall be evaluated on the basis of the following principles:
(a) The evaluation is first and foremost an evaluation of the data, i.e., the documentation that
supports the installation, testing and calibration of the IFR equipment;
(b) This procedure applies both to traditional and non-traditional IFR equipment installations;
(c) The aircraft has to be equipped in accordance with CAR 605.18;
(d) The IFR equipment does not need to be certified in accordance with TSO standards, and
hence does not require authorised release certificates;

This might help too:
https://vansairforce.net/community/show ... p?t=193914

[ahramin]

As photofly has pointed out, none of the equipment needs to be TSO, but then it’s up to you to show that it meets the requirements for IFR when you request the VFR restriction removal. Each time I have had a client questioned by a TC inspector, we were able to get an email from the manufacturer saying that the equipment in question met the TSO requirements. That was always acceptable.

[Bede]

Thanks for the thorough responses. The only thing I can think of is the removal of the VFR restriction that may require the TSO at the individual inspector level.

The reason I was asking the question is that my dad's "handheld" GPS in his RV has all the approaches programmed and someone asked me a hypothetical question. ("Can we legally...")

[photofly]

One reason why non-approved GPS's aren't allowed to be used for approaches is that they don't switch the CDI automatically from en-route to terminal to approach mode (0.3nm fsd) and then back to terminal mode in the missed approach.

Does your father's handheld GPS even drive (or have) a CDI?

[Bede]

One reason why non-approved GPS's aren't allowed to be used for approaches is that they don't switch the CDI automatically from en-route to terminal to approach mode (0.3nm fsd) and then back to terminal mode in the missed approach.

Does your father's handheld GPS even drive (or have) a CDI?

A CDI on the unit. It's a Garmin 696 or something like that. Don't get me wrong, I wouldn't fly IFR in that plane. Someone (my son) just asked me why we couldn't, and I couldn't come up with a CARs reference for him.

[photofly]

One reason why non-approved GPS's aren't allowed to be used for approaches is that they don't switch the CDI automatically from en-route to terminal to approach mode (0.3nm fsd) and then back to terminal mode in the missed approach.

Does your father's handheld GPS even drive (or have) a CDI?

A CDI on the unit. It's a Garmin 696 or something like that. Don't get me wrong, I wouldn't fly IFR in that plane. Someone (my son) just asked me why we couldn't, and I couldn't come up with a CARs reference for him.

The answer might be different depending on whether the question is "can I file IFR and use this for navigation" vs "can I fly a GPS approach with it".