Homebuilt airworthiness standards

[Bede]

Where in the CAR's does it say that you actually have keep homebuilt aircraft in an airworthy condition? Let's say, for sake of argument, flying with a big dent in the wing (as opposed to a U/S radio - CAR 605.08).

CAR 605.84 discusses aircraft meeting limitations related to the type design (homebuilts excepted).
CAR 605.86 discusses following an approved maintenance schedule for all aircraft, but CAR 625 Appendix B doesn't say anywhere that you need to fix defects on an annual inspection, just that they need to be recorded.

Any thoughts?

[digits_]

I find this a very interesting question.

At the very least you need to be able to replace inspection panels according to the maintenance schedule, so those parts of the wings can't be damaged tooo much.

(11) Aircraft Generally, Including Technical Records

(a) Enter details of all deficiencies found during the inspection in the aircraft technical records.

(b) Upon completion of the inspection, replace or close all inspection plates, access doors, spinners, fairings and cowlings.

Source: https://www.tc.gc.ca/eng/civilaviation/ ... b-2459.htm

[ahramin]

I think it has something to do with the aircraft needing a c of a to fly and the c of a requiring the aircraft to be airworthy. Don't have access to the CARs right now but I'll have a look later.

[photofly]

605.03

605.03 (1) No person shall operate an aircraft in flight unless
(a) a flight authority is in effect in respect of the aircraft;
(b) the aircraft is operated in accordance with the conditions set out in the flight authority; and
(c) subject to subsections (2) and (3), the flight authority is carried on board the aircraft.


One of the conditions on the C of A is that the aircraft is maintained in accordance with the applicable requirements of the regulations.

[digits_]

I believe that is the point that Bede is trying to make.

The regulation you mentioned, would lead us to:

Division III — Aircraft Maintenance Requirements
Aircraft Maintenance — General

605.84 (1) Subject to subsections (3) and (4), no person shall conduct a take-off or permit a take-off to be conducted in an aircraft that is in the legal custody and control of the person, other than an aircraft operated under a special certificate of airworthiness in the owner-maintenance or amateur-built classification, unless the aircraft

(a) is maintained in accordance with any airworthiness limitations applicable to the aircraft type design;

(b) meets the requirements of any airworthiness directive issued under section 521.427; and

(c) except as provided in subsection (2), meets the requirements of any notices that are equivalent to airworthiness directives and that are issued by

(i) the competent authority of the foreign state that, at the time the notice was issued, is responsible for the type certification of the aircraft, engine, propeller or appliance, or

(ii) for an aeronautical product in respect of which no type certificate has been issued, the competent authority of the foreign state that manufactured the aeronautical product.

The owner maintenance/amateur built is specifically excluded from the requirement to maintain it in accordance with any airworthiness limitations.

[AirFrame]

CAR 625 Appendix B doesn't say anywhere that you need to fix defects on an annual inspection, just that they need to be recorded.

Two things come to mind...

First, if you have something that affects your structure (as a big dent in a wing would) logged as a defect and you chose to fly again after that, and if something went wrong and you crashed into a shopping mall and killed thousands, your insurance company may look at that and decide you made a poor decision to fly a damaged aircraft... Pilot error... Your fault... No insurance. I know, there's a lot of "ifs" there. But it's a way for Transport to be able to point to something that says "he knew the airplane had a problem and flew anyway." Do our insurance policies have wording in them that may cover this in some way?

Second, 625 App B is a list of things to check, but I thought the intent was that if you found something wrong during that check, that you would repair it... I don't know if that's written as law anywhere though.

It's a good question though... It would be interesting to hear what Transport says about it if someone here can't find the right chapter and verse that explains it.

[photofly]

owner maintenance/amateur built is specifically excluded from the requirement to maintain it in accordance with any airworthiness limitations.

Airworthiness limitations are distinct from the requirement for airworthiness.

By the same token there's no requirement to maintain a certified aircraft.

However if either type of aircraft isn't airworthy the C of A is not in effect and you have no flight authority.

The alternative if your aircraft isn't airworthy is a flight permit, for which someone (an AME for a certified aircraft) has to sign that it's safe for the intended flight.

[ahramin]

Second, 625 App B is a list of things to check, but I thought the intent was that if you found something wrong during that check, that you would repair it... I don't know if that's written as law anywhere though.

Not at all. You are never going to find a law that requires any maintenance on an aircraft on the ground, only laws that require maintenance be done before flight. The requirement for an annual inspection is for the inspection only and whether or not any defect found needs to be repaired is completely separate and subject to the same standards as defects found the rest of the year.

Bede I think we can sum it up thus:

1. There is a requirement somewhere in the CARs for the aircraft to have a C of A (briefly I couldn't find it but I think it can be stipulated)

2. The C of A carries a condition that the aircraft must be maintained in accordance with the CARs

3. CAR 605.10 says that you cannot fly with unserviceable equipment unless certain provisions have been met

So if you have a dent in the wing but you decide the wing is still serviceable (and can justify your decision), then no problem. If you decide it is not serviceable, then you can't go flying until either it is repaired, or you document that the wing isn't serviceable and determine that it isn't needed.

[photofly]

You don’t need a C of A, you need a flight authority (605.03(1)(a))

And that is defined as:

flight authority means a certificate of airworthiness, special certificate of airworthiness, flight permit or validation of a foreign document attesting to an aircraft’s fitness for flight, issued under Subpart 7 of Part V, or a foreign certificate of airworthiness that meets the requirements of Article 31 of the Convention; (autorité de vol)

Additionally:

507.11 Unless surrendered, suspended or cancelled, a flight authority issued pursuant to this Subpart remains in force during the period or for the number of flights specified in it or, where no limit is specified, indefinitely, if the aircraft continues to meet the conditions subject to which the flight authority was issued.


Additionally:

507.02 Where an application for a flight authority is made pursuant to section 507.06, the Minister shall issue a certificate of airworthiness in respect of an aircraft
(a) for which an aircraft type design has been certified by the Minister and the certification is not in respect of a restricted category aircraft;
(b) that conforms to its certified type design; and
(c) that is safe for flight.

Or for a home built:

507.03 Where an application for a flight authority is made pursuant to section 507.06, the Minister shall issue a special certificate of airworthiness in respect of an aircraft that
(a) meets the criteria for one of the classifications of a special certificate of airworthiness specified in Chapter 507 of the Airworthiness Manual;
(b) conforms to the applicable type design or, in the case of an amateur-built aircraft, is designed and constructed in a way that ensures its airworthiness, in conformity with the requirements of Chapter 549 of the Airworthiness Manual; and
(c) is safe for flight.

So if your homebuilt aircraft doesn’t meet the condition (b) of being airworthy in 507.03, being a condition under which the special C of A was issued, the flight authority is no longer in force, and to fly it would breach 605.03(1)(a).

[digits_]

The only part that refers to maintenance in Chapter 549 is:

549.19 Inspections and Maintenance

(a) During fabrication and after final assembly the aircraft shall be inspected for workmanship and general serviceability according to a schedule acceptable to the Minister. Particular attention shall be paid to enclosed areas of the primary structure, which are not visible after final assembly.

Information Note:

(Ref. AMA 549/1A, paragraph 7).

(b) In accordance with Chapter 507, paragraph 507.325(d), an annual inspection is required to keep in force the Special Certificate of Airworthiness for amateur-built aircraft.

[(c) The inspection shall show that the maintenance requirements set out in Chapter 571, paragraph 571.101(a) are met.]

There is also a list of required functional equipment. But nothing else in those regulations. A wing is not mentioned for example.

It looks to me that 605.10 is the one that requires you to fix a broken wing on a home-built.

[photofly]

A wing is not "equipment", and there is no difference between homebuilts and certified aircraft. In all cases, a flight authority is needed for lawful flight, and the C of A (special or regular) is not in force if the aircraft at any time is not in a condition to meet the requirements under which the C of A was issued.

[digits_]

A wing is not "equipment", and there is no difference between homebuilts and certified aircraft. In all cases, a flight authority is needed for lawful flight, and the C of A (special or regular) is not in force if the aircraft at any time is not in a condition to meet the requirements under which the C of A was issued.

Ok, but what requirements are you referring to? The quoted regulations refer to the airworthiness manual for home-builts: https://www.tc.gc.ca/eng/civilaviation/ ... tm#549.101. Is that the only one you are referring to, or is there another one that I've missed?

A damaged wing (that can still meet the required climb performance) is still in a condition to meet the requirements of the above mentioned airworthiness manual.

[ahramin]

While a wing is not "equipment" by the strict definition, the same rules apply. See (iii) below. The point being that any defect must be evaluated before flight and the PIC takes responsibility for the decision to go flying with that defect.

625.10 Unserviceable Equipment - Aircraft without a Minimum Equipment List
Information Note:

The following provisions, although considered advisory in nature, have been included in the main body of these standards due to their importance. They are not standards.

(i) CAR 605 requires that all equipment listed in the applicable airworthiness standard, and all equipment required for the particular flight or type of operation, must be functioning correctly prior to flight. The requirement for a particular system or component to be operative can be determined by reference to the type certificate data sheet, operating regulations or the applicable equipment list in the aircraft operating manual.

(iii) Defects (e.g. buckling, cracks, extensive corrosion) of the skin or structure of the aircraft or of the pressure hull of a pressurized aircraft beyond the safe limits established by the manufacturer in his maintenance manual or other approved maintenance instructions will render that aircraft unfit for safe operation.

(iv) In the case of an aeroplane or helicopter not operated pursuant to Part IV, or an aircraft not operated pursuant to Part VII, the pilot must review the log prior to flight and decide whether any of the defects recorded affect the airworthiness of the aircraft. Reference may be made to the type certificate data sheet, the aircraft operating manual, or any list provided by the aircraft manufacturer respecting equipment that must be operational for the intended flight. Any or all of these may indicate that particular items of equipment are mandatory.

(vi) Where in doubt, the pilot should obtain the advice of an AME. This is best done by requesting the AME to inspect the defective system or component to determine its effect upon the aircraft's fitness for flight. By following this procedure and obtaining the AME's signature in the log book in the form of a maintenance release, the pilot will be able to demonstrate, if necessary, that he has taken all reasonable steps to ensure the airworthiness of the aircraft. Inspection of defective systems by an AME, although advisable, is not a legal requirement. As stated earlier, it is the pilot's responsibility to determine whether the aircraft is fit for the intended flight.

(ix) The final decision, however, still rests with the pilot. A pilot who accepts an aircraft with defects, the repair of which has been deferred in accordance with an approved system, has a good defence against any possible charge of flying an unairworthy aircraft, whereas a pilot who undertakes a flight with an aircraft that is not in compliance with the approved system to control the deferral of repairs to defects commits an offence.

[photofly]

A wing is not "equipment", and there is no difference between homebuilts and certified aircraft. In all cases, a flight authority is needed for lawful flight, and the C of A (special or regular) is not in force if the aircraft at any time is not in a condition to meet the requirements under which the C of A was issued.

Ok, but what requirements are you referring to? The quoted regulations refer to the airworthiness manual for home-builts: https://www.tc.gc.ca/eng/civilaviation/ ... tm#549.101. Is that the only one you are referring to, or is there another one that I've missed?

A damaged wing (that can still meet the required climb performance) is still in a condition to meet the requirements of the above mentioned airworthiness manual.

Lots of aircraft fly lawfully with minor wing damage - all sorts of hangar-rash dents don’t get repaired. As long as the aircraft is in a condition that meets the requirements for the issue of its C of A (complies with chapter 549 as appropriate AND is airworthy, safe for flight, plus meets any additional conditions printed on the C of A such as is maintained in accordance with the regulations) the C of A remains in force and it may be lawfully flown.

Ahramin just posted the non-regulatory advice that TC issued that makes it clear the government considers the final determination of airworthiness and safe-for-flight lies with the prospective PIC.

It does seem clear to me that a pilot who flies an un-airworthy aircraft (without a flight permit etc.) has no flight authority and breaches 605.03.

[Bede]

Thanks for the great replies guys. I think that pretty much answers it.

[AirFrame]

Isn't there something that requires that the person saying the aircraft is safe can *show* that the aircraft is safe in some way (other than by flying it, which may not exercise it to the limits of its abilities)?

If the airplane has no visible damage, one could argue that it's condition matches it's as-designed state and in all likelihood will perform as required. But if there's a dent in a wing, which compromises the monocoque structure of the wing in that area and limits its load-carrying capability, how does the PIC show how much load reduction is appropriate or prudent?

Can the PIC look at the damage from running a wing into a fence post, decide "as PIC I say that'll hold together to fly home again" and do it?

[ahramin]

Airframe the short answer is yes. It is up to the PIC to determine if the aircraft is airworthy or not. If in doubt, pilots are encouraged to have an AME inspect the damage and make an entry in the logbook that it is still airworthy but there is no requirement to do so. You are completely legal making the determination on your own. It's not about "holding together" though, it's about airworthiness. Will the aircraft still perform properly? Will it still be controllable? What if severe turbulence is encountered? In your example if the dent is affecting the wing's ability to carry a load then I don't see how a pilot could justify saying that airworthiness isn't affected without an engineering analysis. On the other hand if a dent doesn't affect the structure and will not appreciably reduce the performance, it's quite possible that it's airworthy and that a builder would have the knowledge to determine that.

Basically it is a 3 step process.

1. Document the damage,
2. Decide if you have the knowledge to make the decision,
3. Inspect, look up references, and make the decision.

In the case of damage to the aircraft structure like your fence post example, I am rarely confident that I know the difference between airworthy and not, so I'm unlikely to move on to step 3 on my own. On the other hand, propeller damage is something I can look up in 43.13 and my propeller manual and I would have no problem deciding whether or not to fly. Similarly damage to fairings or stab tips are easy to determine as non airworthiness items since they are optional on my aircraft. A client of mine had a propeller overspeed and was completely devastated thinking that he would have to get an AME to tear down his engine in order to be legal. After a brief discussion, we downloaded the engine monitor data, looked up the Lycoming Service Instruction, and confidently determined that no further action was required. Took about 10 minutes, no AME required.

[photofly]

Can the PIC look at the damage from running a wing into a fence post, decide "as PIC I say that'll hold together to fly home again" and do it?

No.

The PIC can decide that the aircraft is airworthy, but it’s perfectly possible that he or she is wrong, and may have to answer for the consequences. That is, the PIC has to decide, but there is an objectively right or wrong answer in each case (or as close as you can get, in aviation). It’s not a matter of individual preference or discretion.

But if you think it’s safe “to fly home” only, then it’s clearly not airworthy, and the C of A cannot be in force. You can only say it’s safe to fly home if you think it’s equally safe to fly anywhere else because it doesn’t need repair. And you still might be wrong.

One exception would be if a piece of equipment needed for a particular flight is inoperative: for example your HSI is u/s. So you can’t fly under IFR, but you could under VFR, if the equipment is removed or disabled, relevant placard is installed etc.

The alternative for your example is to acknowledge it’s not airworthy, and have an AME (or the owner, I guess, for a home built) inspect it and sign it as safe for the proposed flight on an application for a flight permit back to base (which will be day VFR only and may have other conditions). On payment of the fee, TC will approve, send you a permit (which you must carry on board) then you can fly as permitted home, then repair it there. After the repair is completed in accordance with regulation, and the aircraft is airworthy again, the C of A comes back into force as a flight authority.

[AirFrame]

In your example if the dent is affecting the wing's ability to carry a load then I don't see how a pilot could justify saying that airworthiness isn't affected without an engineering analysis. On the other hand if a dent doesn't affect the structure and will not appreciably reduce the performance, it's quite possible that it's airworthy and that a builder would have the knowledge to determine that.

This is the situation I was wondering about. Keep in mind that a good percentage of Amateur-Built Aircraft in Canada are not owned by builders. A builder, yes, could probably make an educated guess how bad the damage is. A non-builder could walk out to the wingtip, give it a shake, and say "it seems solid, and because i'm allowed to say so, I deem it safe! Let's go fly!" I thought there was something more concrete in the rules that required more due diligence, but I don't know where (or if) there is.

[photofly]

A non-builder could walk out to the wingtip, give it a shake, and say "it seems solid, and because i'm allowed to say so, I deem it safe! Let's go fly!" I thought there was something more concrete in the rules that required more due diligence, but I don't know where (or if) there is.

There doesn't need to be more about due diligence, because the pilot's own opinion is not relevant. There is an objectively correct answer to the question, and the pilot has the responsibility to investigate to find that correct answer.

It's like asking a pilot to add 2 plus 2 (no jokes please) - just because the pilot thinks or wants the answer to be 3, or feels the answer today should be 3, or doesn't know how to add - doesn't mean the pilot has a defence to having decided the answer is 3. The only correct answer is 4, and it's the pilot’s responsibility to investigate until he or she gets the answer 4.

That the pilot may not have the technical knowledge to determine the correct answer is what is in mind when TC suggests that the advice of an AME is sought.