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Encoders and Transponders for VFR Flight (Canada-Ed.)

Snowflake

Snowflake

Sidney, BC, Canada
Sponsor
It was pointed out to me recently that the CARs seem to say that in Canada your Encoder must be TSO approved. In particular, this standard says that TSOs apply to pressure altitude reporting equipment:

Transport Canada said:
551.103 Transponder and Automatic Pressure Altitude Reporting Equipment
http://www.tc.gc.ca/eng/civilaviation/regserv/cars/part5-standards-551s-1810.htm#551_103
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A pilot I know says he hangs his hat on CAR 551.02 (B):

Transport Canada said:
551.02 Equipment Design Standards
...
(b) Where there are no specific design standards, the equipment must provide the same level of safety as that established by the certification basis of the aircraft.
http://www.tc.gc.ca/eng/civilaviation/regserv/cars/part5-standards-551s-1810.htm#551_02
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Many RV's are being built with EFIS displays intended for amateur-built aircraft (Dynon, GRT, MGL, etc) that provide serial data out specifically to drive a transponder. To my knowledge, none of those EFIS units are TSO certified.

I understand that some avionics shops are testing them anyway as part of the system, and signing them off. Other avionics shops are saying "whoa" and halting the process when there's no TSO'd encoder.

Who's right?
 
A TSO'd encoder or altimeter is NOT required, as long as they meet the spec in CFR 43, app. E it's good to go. I sign them off all the time and most of them are listed on my "Approved" FAA capabilities list (includes Dynon, GRT, G3X, Advanced, etc).

Took a bit (quite a bit) of work to convince the local FSDO of this but in the end they agreed it was legal and now everybody is happy :D.

Note: This applies to USA, not sure about CA rules!
 
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Trevor778 said:
I work for a local avionics shop in the lower mainland and we dont sign out any experimental equipment and provide no log entry as it is the responsibility of the owner to be sure they meet the requirements. We will do your 2 year pitot/static and test your system and provide you with the data we record, but the log entry is entirely up to the owner.
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The owner/builder CANNOT legally sign off on a pitot-static or transponder check and he has no authority to make such an entry in the logbook, end of story.

Sorry but the shop you work for is incorrect.
 
Walt, thanks for the reply, I am aware that in the US, this issue has been hashed to death here and elsewhere, and TSO is not required on the encoders for homebuilts.

The issue appears to be with the Canadian regs, which don't seem to have any clear clarification as to what applies for amateur-built aircraft. That's why this is posted in the Canada sub-forum... :)
 
Have you checked with MDRA head quarters? Surely is has come to their attention if it has been an issue somewhere in Canada. I for one am interested to know. Keep us posted.

Bevan
 
I did get a reply from the RAA, which suggested that builders in central Canada have been getting past this requirement by having their final inspection done with the encoder and transponder removed, and an equivalent weight installed in their place. That way the weight can be removed and the encoder and transponder re-installed with no change to weight and balance. I can't say i'm impressed with that solution.

MD-RA replied today too. Their answer I think makes the most sense, although they offered no regulatory citation to back it up. This is their answer:
MD-RA said:
In Canada we accept non TSO'd equipment in amateur built aircraft. An amateur built aircraft is a non certified aircraft therefore there is no requirement to install TSO'd equipment. In Canada the owner/builder of an amateur built is responsible for his or her aircraft and is the only individual that is eligible to sign out maintenance release's. With regard to out of phase equipment you would employ the services of an avionics shop to test your instruments, perform static pitot test etc. And supply you (the owner) with the pertinent information. (no tag's or certification required ) From the information you would access the serviceability of your instruments and sign in the aircraft log book that the required 24 month check of instruments has been performed and meet's TC criteria.
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That came from the head guy at MD-RA so it should solidly reflect their policy.

As for how you impliment it, I suggest that if your avionics shop doesn't want to sign it off, ask if they'll at least do the testing and tell you whether it passes. Then you do as MD-RA suggests, write up the test in your logbook and say no more about it. If they won't do the test, then find another shop.
 
I have had a couple different shops do my tests. They write up the sticker in my log book of everything that was done, I then have to sign it. Just make sure you understand what they did before signing. Not sure if this is the same for all avionics shops in Canada. I would rather they sign it though:)
 
Rob
I realize that no one wants to carry extra weight, wiring and plumbing. I used the encoder recommended by my avionics shop and they have done my pitot static test and made the required log book entries. If you have any interest in getting the "VFR only restriction" lifted then you are going to need this test from a recognized shop. Encoders are not that expensive and do provide a bit of protection if your effis should go down, at least that way control would know your altitude even if you did not.
 
Further update: I did get an even more authoritative answer for this. Thanks to Allan Mahon at MD-RA, who sent me this clarification from Maurice Simoneau at Transport. Note that while the question was being asked specifically in reference to IFR flight, the question was the same... What TSO requirements are there for "certification" of components. I have included Maurice's reply below. The only edits were to clarify which is a quote from the CARs and which are his words, and I also added updated links to the relevant CARs... They were moved recently and his were deprecated.

In short: TSO approvals are not required for systems on amateur-built aircraft (flying VFR *or* IFR), and the Avionics shop's responsibility ends at conducting the tests and telling the owner/builder whether the systems meet the standards. It's up to the owner/builder at that point to document it and sign it off.

Maurice Simoneau - Transport Canada said:
IFR operations by amateur-built aircraft in Canada are subject to the following rules:

1 - the aircraft has to be equipped in accordance with CAR 605.18;
2 - the "operational" equipment has to comply with CAR 602.59(b);

CAR 602.59(b) said:
no person shall operate an aircraft unless the operational ... carried on board the aircraft ... is functional
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-- "functional" means that the equipment performs its intended function

3 - the equipment does not need be approved in accordance with TSO standards and requirements;
4 - the equipment does not need to be certified -- no requirement for authorised release documents/certificates/tags, such as TCCA FORM 24-0078/FORM ONE, EASA FORM ONE, FAA 8130-3;
5 - the installation does not need to be approved by Transport Canada;
6 - the owner can do the installation and sign the maintenance release for the maintenance activities performed.

Having stated the above, I would invite your client to consult Airworthiness Notice - B032, Edition 2 - 18 April 1996 - Procedure for the Removal of 'Visual Flight Rules Only' Limitation From the Special Certificate of Airworthiness (Amateur-Built Aircraft).

AN B032 was published at a time when the Air Regulations (Air Regs) and Air Navigation Orders (ANOs) were still in effect; the draft version of the Canadian Aviation Regulations [CARs] was the Canada Gazette Part I [Pre-publication] version that was later amended and published as the "new" CARs in October 1996. I have listed below the new regulatory references:

ANO Series V, No. 5 is now CAR 602.137
ANO Series V, No. 11 is now CAR 602.96 to 602.104, CAR 602.125
ANO Series V, No. 22 is now CAR 605.18
CAR 601.03 is still CAR 601.03
CAR 605.17 is now CAR 605.18
CAR 605.29 is now CAR 605.35
CAR 605.67 is now CAR 605.35

I have quoted below those parts of AN B032 that I consider most relevant to the discussion:

AN B032 said:
A statement of compliance signed by the owner shall be attached with the application to remove "VFR ONLY" from the standardized operating conditions. The statement shall indicate that the equipment required for IFR flight as specified in ANO Series V, No. 22 [see CAR 605.18], CAR 601.03, 605.17 [see CAR 605.18], 605.29 [see CAR 605.35] and 605.67 [see CAR 605.35] has been properly installed, tested and calibrated in accordance with Chapters 571 and 575 of the Airworthiness Manual [see Standard 571] or CAR 571, 605 and related standards, and that it functions properly.

The owner must be prepared to demonstrate that the installation, test and calibration of IFR equipment has been appropriately performed". The onus to demonstrate that functionality rests with the amateur-built aircraft owner. The owner has to be able to demonstrate that he/she has the necessary testing equipment to carry out the installation of the IFR equipment, that the testing equipment has been properly tested and calibrated, and that he/she is competent to operate such testing equipment.
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AN B032 said:
although the installation of IFR equipment may be performed by the owner, due to the complexity and cost of test equipment, it may be more practical for this work to be performed by an appropriately rated aircraft Approved Maintenance Organisation (AMO)
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Further to the above, I would also like to direct your client's attention to CAR 551 - Aircraft Equipment and Airworthiness Manual Chapter [STD] 551 - Aircraft Equipment and Installation.

CAR 551.01 said:
(1) subject to subsection (2), the standards of airworthiness for the design and installation of aircraft equipment required by Part VI or Part VII are those specified in Chapter 551 of the Airworthiness Manual.
(2) If no standards of airworthiness are specified in Chapter 551 of the Airworthiness Manual for the design and installation of an item of aircraft equipment, the applicable standards of airworthiness are those that form the basis of certification of the aircraft on which the equipment is installed.
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STD 551 specifies design and installation standards for the following equipment:

Flight Data Recorders
Cockpit Voice Recorders
Ground Proximity Warning Systems
Transponder and Automatic Pressure Altitude Reporting Equipment
Emergency Locator Transmitter
Altitude Alerting Systems
Radiocommunication Equipment
Radio Navigation Equipment

It is my understanding that those design and installation standards apply to all such aircraft equipment, irrespective of the aircraft where the equipment is installed.

STD 551.02(a) said:
... equipment installed or intended for installation in aircraft shall meet the applicable standards of:

(1) Chapter 537 of the Airworthiness Manual; or
(2) this chapter [STD 551], where the equipment was already approved for use on aircraft.

Information Note:

Where a TSO is referenced as an acceptable design standard, it is intended to mean that the design standards contained with the TSO are an acceptable minimum standard and the equipment does not necessarily need to have a TSO. i.e. an applicant could obtain Transport Canada Civil Aviation approval (Supplemental Type Certificate/Limited Supplemental Type Certificate) for a design if it is demonstrated that it complies with the design standards specified in the applicable TSO.
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Please let me know if I have answered your questions fully.

Maurice A. Simoneau

Senior Civil Aviation Safety Inspector / Inspecteur principal de la s?curit? de l'Aviation civile
Recreational Aircraft / A?ronefs de loisir
Maintenance and Manufacturing Standards / Normes de maintenance et de construction
Standards Branch / Direction des normes
telephone/t?l?phone: 613-990-9490
facsimile/t?l?copieur: 613-952-3298
[email protected] <mailto:[email protected]>.
Transport Canada Civil Aviation, Place de Ville [AARTM], Ottawa Canada, K1A 0N8
Transports Canada Aviation civile, Place de Ville [AARTM] Ottawa Canada, K1A 0N8
<http://www.tc.gc.ca/>

Government of Canada / Gouvernement du Canada
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Good work, Rob. You should write an article for the RAA Flyer newsletter on this, and even COPA Flight News. It's important.

V
 
Thanks a bunch, Rob

I, for one, certainly appreciate this information. I have installed sufficient equipment in my Rocket for IFR flight, but have had a niggling worry about whether I will be able to actually use it. I suspected there must be a way because others have done so, but it is great to have this spelled out.
 
I don't think that conclusion avoids TSO:

"In short: TSO approvals are not required for systems on amateur-built aircraft (flying VFR *or* IFR), and the Avionics shop's responsibility ends at conducting the tests and telling the owner/builder whether the systems meet the standards. It's up to the owner/builder at that point to document it and sign it off."

The key element (and challenge) of the Transport Canada response is that equipment for which a design standard is specified by a TSO (like the transponder and encoder) does not have to have the TSO if it is demonstrated that the equipment complies with the design standards specified in the applicable TSO.
One may say based on that that "it is up to the owner/builder to document it and sign it off", but there is no way that an owner/builder can do that - TSO design standards are much more than showing that the thing works - how can an owner determine and demonstrate that each element of a TSO design standard is met?
I think that the correct concusion is that in Canada, such things as the transponder and encoder must be certified - which is really not a big deal.
That is a different issue than the required bi-annual equipment checks for IFR - I understand that for those, a shop can perform the tests, provide the results to the owner, and the owner can rely on the test results to make the log entry.
Bill Brooks
Ottawa, Canada
RV-6A finishing kit
 
C-GRVT said:
I think that the correct concusion is that in Canada, such things as the transponder and encoder must be certified - which is really not a big deal.
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Except, Maurice Simoneau himself says that's not the case:
Maurice Simoneau said:
3 - the equipment does not need be approved in accordance with TSO standards and requirements;
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C-GRVT said:
That is a different issue than the required bi-annual equipment checks for IFR - I understand that for those, a shop can perform the tests, provide the results to the owner, and the owner can rely on the test results to make the log entry.
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That's what prompted this entire discussion... A shop was refusing to perform checks on an aircraft that used a Dynon display (non-TSO) to drive a Garmin 327 (TSO). The owner in question was not interested in IFR flight, only VFR, but the shop didn't care and said that they couldn't do it because it wasn't a TSO encoder.
 
Bill,

I am not a lawyer, but I find the reference to CAR 521 in the Application section of CAR 551 interesting.

Transport Canada said:
551.01 Application

Pursuant to subsection 521.31(2) of the Canadian Aviation Regulations (CARs), this Chapter specifies standards of airworthiness for the design and installation of aircraft equipment required by Part VI or Part VII of the CARs.
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CAR 521 covers approval of type designs, and its application section says:

Transport Canada said:
521.02 This Subpart applies to applicants for and holders of the following documents and applicants for a change to one of those documents:

(a) a type certificate issued under section 521.57 in respect of an aeronautical product;

(b) a Canadian Technical Standard Order (CAN-TSO) design approval issued under section 521.109 in respect of an appliance or a part;

(c) a supplemental type certificate issued under section 521.206 in respect of an aeronautical product;

(d) a repair design approval issued under section 521.256 in respect of an aeronautical product; and

(e) a part design approval issued under section 521.306 in respect of a replacement part for an aeronautical product.
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Amateur-built aircraft have no approved type design, and are not subject to CAR 521. The application statement in CAR 551 would seem to only apply to aircraft which had an approved type design. At the very least, the situation appears quite ambigous. Comments?

Note - I agree 100% with your comment that it is not practical for us to show that a non-TSO'd altitude encoder meets all the requirements of the TSO. I've read many TSOs, and the SAE specs that are enabled by the TSOs. The test requirements are usually quite extensive, and include a wide range of tests at extreme environmental conditions.
 
I just recently had the VFR only restriction lifted from my aircraft. I have a completely different view of IFR equipment requirements now, then I did prior to my flight training. Six months ago I felt that I needed the bare minimum equipment that is legally required, now I want much more. One of the most satisfying things that I have done in my airplane was a descent through a cloud layer to minimums, 500agl, at our local airport. This could not be done without complete confidence in my equipment and the testing of that equipment.
The letter from Mr. Simoneau has clearly not made the rounds of the Avionics shops in Canada, nor has it made it to all the TC offices. If I was the owner of an Avionics shop there is no way I would sign off a piece of equipment that could be used in the IFR environment if it was not TSO certified. And if you have a VFR plane and you are going into a class C or B airspace then you are in an IFR environment and that equipment better be giving the correct information. How could any avionics shop know what standards all these small effis shops use for their equipment. As a private shop I do not believe they are obligated to do work on any equipment and as such individuals may have to look for a shop that will sign off that the equipment does meet the standards. And then you, the builder, can sign your name in your log book that this equipment meets the standards. The letter clearly states that we would have to demonstrate that the equipment meets the standards of TSO'd and essentially, for the most of us that means using a certified encoder.
Although we may have the right to use this non TSO'd equipment perhaps we will not always have the means to do so.
Encoders are not expensive! ACS has many options starting at $175.
I agree with Bill Brooks assessment of the issue
 
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Tom, while I agree wholeheartedly that you want to be sure that your equipment is functioning properly, as is the equipment of those around you, I think it's silly to suggest that only TSO'd equipment that has gone through extensive, expensive testing can meet that requirement.

With very few changes to your reply above, your position could be equally used to suggest that amateur-built aircraft are a poor substitute for certified aircraft. We are allowed to take our "unproven" (by certification standards) designs and fly them in IFR conditions too, with only annual inspections to confirm that they are safe. We don't even have to test our aircraft to their design limits... We look at things that can be inspected, and from that infer that the design as a whole is reasonable.

I believe the same can be done with an AHARS driving a Transponder, allowing me to forego the extra weight, complexity of wiring, and another possible point of failure. I'm glad that Transport (via Mr. Simoneau) agrees.
 
I have heard of many more encoder failures than EFIS failures. If safety is the number one concern, I would put my money on a proven EFIS with a battery back-up rather than an external encoder.

Also, if the EFIS altitude system fails, it's obvious to the pilot and a backup can be used, along with verbal reporting to ATC of a non-valid mode C. A spotty encoder may not be detected at all.

So it's not the $175 for an encoder... it's the increased probability of an undected fault that's the problem.

So if the regs permit it, I prefer to use the EFIS encoder: known reliability, battery backup and less plumbing and wiring.
 
Quick, slightly off-topic question: Is a VFR-only amateur-built required to do the 24 month transponder/encoder recertification for operation in controlled airspace? I purchased my 6A last summer from the US and can find no record in the logs regarding when, or if, the system has ever been tested in the past.
 
Gerry: Yes, VFR-only amateur-built aircraft are required to have the same 24-month checks. That's what prompted this whole discussion, an owner in Alberta was told by his shop that they couldn't inspect his system as he didn't have a TSO'd encoder.
 
gerrychuck said:
Quick, slightly off-topic question: Is a VFR-only amateur-built required to do the 24 month transponder/encoder recertification for operation in controlled airspace? I purchased my 6A last summer from the US and can find no record in the logs regarding when, or if, the system has ever been tested in the past.
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Hi Gerry! BTW, Dave and I made it back from Moose Jaw to Victoria in one day. We were bagged, but that's what happens with slight hypoxia and a jug of beer at the end of the journey. Thanks for all your help.

To answer your question, yes you need to have the altimeter checked every 24 months if you fly class B, C or D airspace and the transponder/encoder checked every 24 months regardless of where you fly. If you have an encoding altimeter (EFIS), this collapses to check your EFIS and transponder every 24 months.
 
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gerrychuck said:
Quick, slightly off-topic question: Is a VFR-only amateur-built required to do the 24 month transponder/encoder recertification for operation in controlled airspace? I purchased my 6A last summer from the US and can find no record in the logs regarding when, or if, the system has ever been tested in the past.
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Short answer - It's even more complicated than you feared. The altimeter is also implicated. And the transponder and altitude encoder must be checked, no matter what type of airspace you fly in.

Long answer follows, with some of the regs paraphrased as the actual wording is hard to follow.

CAR 605.86 requires that the aircraft be maintained in accordance with a maintenance schedule that conforms to the standards in CAR 625.86, or is otherwise approved by the minister of Transport.

CAR 625.86 provides details on which maintenance schedules are required for various types of aircraft, in different types of operation. It also details how to determine when tasks are due.

Appendix B and Appendix C to CAR 625 provide detailed maintenance schedules that are approved by the minister of Transport. Appendix B provides the items that must be completed during the annual inspection. Appendix C covers items that have other intervals, such as altimeters, transponders, altitude encoders, propellers, tachometers, ELTs, compasses, etc.

Altimeters - "Altimeters and other Altimetry devices installed in aircraft operating under Instrument Flight Rules, or under visual flight rules in Class B and C Airspace or Class C and D Airspace that is designated as "Transponder Airspace" shall be calibrated at intervals not exceeding 24 months, to the parameters and tolerances outlined in Appendix B of Standard 571 ..."

Transponders - "ATC Transponders, including any associated altitude sensing reporting mechanisms, where installed, shall be tested every 24 months, in accordance with Appendix F of Chapter 571 of the Airworthiness Manual."

So, you can fly without having the altimeter checked, if you avoid Class B and Class C airspace, and you avoid Class D airspace where transponders are required. But, the transponder and altitude encoder, if installed, must be checked no matter what airspace you fly in.

Note: CAR 625 Appendix B states that you must make an entry in the technical logs (airframe logbook, or journey log) stating which maintenance schedules are being used. E.g. "This aircraft will be maintained in accordance with CAR 625 Appendix B and C".
 
I had a chat with my avionics shop this morning. Last year they spent quite a bit of time trying to get approval to use Blue Mountain equipment as an encoder source. There was no way that they could prove that it met the same standards/criteria as is set out for TSO'd equipment. This technician was not sure that there was anyone in Canada who has the type of equipment/lab could prove that our EFFIS type encoders would meet the same requirements.
Mr. Simone stated that you could use them in our aircraft; he probably knew that there were no shops here that could test them.
Another issue that we have not discussed it that pitot static tests are done on the ground and assume that your static system is accurate. Thus you can have a perfect system on the ground but static errors can give you larger errors on altitude readings.
Kevin Horton would be far better qualified then I am to discuss this topic as he has worked on this issue before for our amateur built aircraft.
 
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Thanks; that's what I thought, but it never hurts to get confirmation. Interesting that it isn't part of the import process.

Good to hear from you Vern; I did hear from Dave after you made it to Vic. Glad the trip went well!
 
Encoders & Static System

Question

Has anyone ever seen "TSO" specifications for an encoder or are there just performance requirements that can be met with proper testing?

Static systems -another post noted.

"Another issue that we have not discussed it that pitot static tests are done on the ground and assume that your static system is accurate. Thus you can have a perfect system on the ground but static errors can give you larger errors on altitude readings."

I have never considered this an issue, many certified non pressurized aircraft such as a Cessna 182 and my RV-6A and RV-7A have less than a fifty foot difference in altimeter readings (and IAS +/- 5) when the Alternate static valve is opened/closed with various cabin heat or air vent settings. Many aircraft would meet altimetery requirements without a static system.

This past Saturday, as a flight of two, we were commenting about how accurate our Dynon & GRT EFIS altimeters were when compared to each other and a 7630' mountain peak. (no we did not do temp/pressure corrections).
 
George
The static position and stock static port as suggested by Van's for their aircraft has been a good choice. Often, in the experimental world, builders make changes and static port location can have a large impact on both your altimeter and your airspeed indicator. Many RVs with flush static ports have reported numbers that were not the same as the aircraft that they were flying with.
 
Tom Martin said:
Another issue that we have not discussed it that pitot static tests are done on the ground and assume that your static system is accurate. Thus you can have a perfect system on the ground but static errors can give you larger errors on altitude readings.
Kevin Horton would be far better qualified then I am to discuss this topic as he has worked on this issue before for our amateur built aircraft.
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Tom,

Static system position errors are a potential very significant safety issue if you fly IFR, as they can result in your altimeter reading too high or too low. This could be a big deal during an instrument approach. But, they are also a potential issue if you fly VFR, as they can lead you to fly at a different altitude than your altimeter says you are, reducing the altitude clearance to other traffic. They also affect the altitude that the TCAS system on other aircraft believes your aircraft is at, which can reduce the ability of TCAS to provide guidance that leads the other aircraft to avoid smashing into you.

This is covered on type-certificated aircraft by design requirements that the static system position error be fairly low. Then, there is an approved production process that is intended to ensure that all aircraft of that model are identical, which in theory ensures that all aircraft of that model have similar shapes around the static ports, and thus have similar errors.

I am not aware of any civil aviation authority that requires amateur-built aircraft to have static system position errors to be checked. It is up to us, due to our personal desire to have a safe aircraft, to ensure that our static systems have errors that are not too high. I have published test procedures and data analysis spreadsheets that builders can use to determine how much static system position error their aircraft has.
 
George in Langley BC said:
Question

Has anyone ever seen "TSO" specifications for an encoder or are there just performance requirements that can be met with proper testing?
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I looked at them years ago, out of curiousity. My recollection is that there were a number of accuracy requirements, including testing under a wide range of temperatures and power supply voltages, and after the encoder had been subjected to specified levels of vibration, humidity, etc.

The TSOs are publically available. But, the bulk of the technical requirements are usually in an SAE or RTCA document that must be purchased. I have access to the SAE and RTCA docs at work, and will sneak another peek next time I get a chance to see if my above description misses anything important.
 
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