Carb heat broken, ok to fly?

[Sundancer]

Efff it. . .if I determined icing wasn't in the cards, I'd fly it. Then have it seen to afterwards, or, if a rental, write it up. "It broke in flight, when I pulled it on when reducing power for descent".

That said, if you (OP) weren't good with it, you did the right thing. We don't all have to think alike.

 

[Tom-D]

You legally can't. It is required by the certification basis (CAR3.XXXX mentioned earlier, post #66).

(a) Except as provided in paragraph (d) of this section, no person may take off an aircraft with inoperative instruments or equipment installed unless the following conditions are met:

(1) An approved Minimum Equipment List exists for that aircraft.

(2) The aircraft has within it a letter of authorization, issued by the responsible Flight Standards office, authorizing operation of the aircraft under the Minimum Equipment List. The letter of authorization may be obtained by written request of the airworthiness certificate holder. The Minimum Equipment List and the letter of authorization constitute a supplemental type certificate for the aircraft.

After reading that, Tell me how many C-172s operating in part 91 have such a letter.
So, How does this apply?
(4) A determination is made by a pilot, who is certificated and appropriately rated under part 61 of this chapter, or by a person, who is certificated and appropriately rated to perform maintenance on the aircraft, that the inoperative instrument or equipment does not constitute a hazard to the aircraft.

An aircraft with inoperative instruments or equipment as provided in paragraph (d) of this section is considered to be in a properly altered condition acceptable to the Administrator.

 

[Tom-D]

Not the way I’m reading it.

Do you believe that the FAA gave pilots the discretion to make decisions?

(4) A determination is made by a pilot, who is certificated and appropriately rated under part 61 of this chapter, or by a person, who is certificated and appropriately rated to perform maintenance on the aircraft, that the inoperative instrument or equipment does not constitute a hazard to the aircraft.

An aircraft with inoperative instruments or equipment as provided in paragraph (d) of this section is considered to be in a properly altered condition acceptable to the Administrator.

 

[MauleSkinner]

Do you believe that the FAA gave pilots the discretion to make decisions?

(4) A determination is made by a pilot, who is certificated and appropriately rated under part 61 of this chapter, or by a person, who is certificated and appropriately rated to perform maintenance on the aircraft, that the inoperative instrument or equipment does not constitute a hazard to the aircraft.

An aircraft with inoperative instruments or equipment as provided in paragraph (d) of this section is considered to be in a properly altered condition acceptable to the Administrator.

I believe you can't be selective about which part of the reg you choose to comply with...you have to comply with the whole thing.

 

[JAWS]

Do you believe that the FAA gave pilots the discretion to make decisions?

Yep. And they can be sanctioned if they make the wrong one.

that the inoperative instrument or equipment does not constitute a hazard to the aircraft.

Lack of carb heat is a hazard to the aircraft. A pilot lost his licence for 30 days for using his discretion incorrectly.

Lack of cabin heat is not a hazard. A broken trim cable is a hazard. A burned out reading light is not a hazard. A burned out gear indication light is a hazard.

 

[midlifeflyer]

(a) Except as provided in paragraph (d) of this section, no person may take off an aircraft with inoperative instruments or equipment installed unless the following conditions are met:

(1) An approved Minimum Equipment List exists for that aircraft.

(2) The aircraft has within it a letter of authorization, issued by the responsible Flight Standards office, authorizing operation of the aircraft under the Minimum Equipment List. The letter of authorization may be obtained by written request of the airworthiness certificate holder. The Minimum Equipment List and the letter of authorization constitute a supplemental type certificate for the aircraft.

After reading that, Tell me how many C-172s operating in part 91 have such a letter.
So, How does this apply?
(4) A determination is made by a pilot, who is certificated and appropriately rated under part 61 of this chapter, or by a person, who is certificated and appropriately rated to perform maintenance on the aircraft, that the inoperative instrument or equipment does not constitute a hazard to the aircraft.

An aircraft with inoperative instruments or equipment as provided in paragraph (d) of this section is considered to be in a properly altered condition acceptable to the Administrator.

You quoted (d)(4) but seem to be disregarding (d)(1)-(d)(3) with the "ands" separating them.

As you say, it is a simple regulation. If the specific N-number has a MEL or a letter of authorization, you follow that. If it doesn't, you follow 91.213(d) - all of it, not some of it.

 

[LoLPilot]

He's asking if he made the right call to scrub the flight. Legal or not I'd argue that this classifies as personal minimums - even if you can, is it prudent? My impression is that everyone here said it was prudent not to fly. As far as billing goes, I had a "flight" where a plane didn't build up enough oil pressure to get into the green arc at runup. The engine was running all of 10 minutes or so between start (where pressure was low at idle but still registered), getting weather, and doing the runup. I wasn't billed for that, but if I had run the engine longer they probably would have billed me for it. Maybe ask the FBO if you can have the plane charges scrubbed because of mechanical failure.

 

[midlifeflyer]

He's asking if he made the right call to scrub the flight. Legal or not I'd argue that this classifies as personal minimums - even if you can, is it prudent? My impression is that everyone here said it was prudent not to fly. As far as billing goes, I had a "flight" where a plane didn't build up enough oil pressure to get into the green arc at runup. The engine was running all of 10 minutes or so between start (where pressure was low at idle but still registered), getting weather, and doing the runup. I wasn't billed for that, but if I had run the engine longer they probably would have billed me for it. Maybe ask the FBO if you can have the plane charges scrubbed because of mechanical failure.

It's definitely a good ADM call even if it were legal.

But I generally don't consider "I guess I'll comply with the rules today" a "personal minimum," although I'm sure to some folks it is

 

[LoLPilot]

It's definitely a good ADM call even if it were legal.

But I generally don't consider "I guess I'll comply with the rules today" a "personal minimum," although I'm sure to some folks it is

Agreed, but in the OP I never saw a question of "did I follow the regs." I saw a question of "did I make the right decision." It's like if he said vis was 3 miles with 2500 foot ceilings. I mean yeah legally you could do it but do you really want to? I sure wouldn't.

 

[MauleSkinner]

Agreed, but in the OP I never saw a question of "did I follow the regs." I saw a question of "did I make the right decision." It's like if he said vis was 3 miles with 2500 foot ceilings. I mean yeah legally you could do it but do you really want to? I sure wouldn't.

Whether the OP knew it or not, he was asking a question that’s answered by legality...he just wasn’t aware of the applicable regulation.

But as someone whose VFR minimums are generally 600&1, I find the analogy amusing.

 

[LoLPilot]

Whether the OP knew it or not, he was asking a question that’s answered by legality...he just wasn’t aware of the applicable regulation.

But as someone whose VFR minimums are generally 600&1, I find the analogy amusing.

You and your superhuman abilities!

 

[Tom-D]

Yep. And they can be sanctioned if they make the wrong one.

There are rules to follow. 91.213 says that you can not remove equipment that are required by 91.205.

carb heat is not one of those required by 91.205

 

[Dan Thomas]

There are rules to follow. 91.213 says that you can not remove equipment that are required by 91.205.

carb heat is not one of those required by 91.205

It's required by the aircraft's type certification. A relevant excerp from the NTSB report posted a few posts back:

In response, the Administrator maintains that the
unavailability of carburetor heat was serious: respondent should
have known the aircraft was not in compliance with its type
certificate and was unsafe to operate. Before an aircraft may be
considered airworthy, it "(1) must conform to its type
certificate, if and as that certificate has been modified by
supplemental type certificates and by Airworthiness Directives;
and (2) must be in condition for safe operation." Administrator
v. Doppes, 5 NTSB 50, 52 n.6, citing Section 603(c) of the
Federal Aviation Act of 1958 (49 U.S.C. §1423(c)).

So go ahead and defer it, and when the airplane crashes you can argue it in court. The sections that refer to deferring "inoperative equipment" is talking about stuff like radios or gyros that are not required for the flight anticipated, such as deferring an attitude indicator in day VFR, or a transponder for a flight in airspace where it's not required. It sure isn't giving authority to defer a busted engine control.

 

[Tom-D]

It's required by the aircraft's type certification.

You seem to forget.

An aircraft with inoperative instruments or equipment as provided in paragraph (d) of this section is considered to be in a properly altered condition acceptable to the Administrator.

Follow the rule.

 

[MauleSkinner]

You seem to forget.

An aircraft with inoperative instruments or equipment as provided in paragraph (d) of this section is considered to be in a properly altered condition acceptable to the Administrator.

Follow only the portion of the rule that I like.

FTFY

 

[midlifeflyer]

There are rules to follow. 91.213 says that you can not remove equipment that are required by 91.205.

carb heat is not one of those required by 91.205

You are still refusing to read it all. 91.213 says you can't fly with inop equipment if it is (quoting the reg)

(i) Part of the VFR-day type certification instruments and equipment prescribed in the applicable airworthiness regulations under which the aircraft was type certificated;
(ii) Indicated as required on the aircraft's equipment list, or on the Kinds of Operations Equipment List for the kind of flight operation being conducted;
(iii) Required by § 91.205 or any other rule of this part for the specific kind of flight operation being conducted; or
(iv) Required to be operational by an airworthiness directive;

91.205, the "Tiny Rule Given Giant Status by Poor Ground Instruction" isn't even in first position, but you choose to skip the one which is.

I guess those who follow rules follow them and those who don't try to make up reasons they don't have to.

 

[Tom-D]

You are still refusing to read it all. 91.213 says you can't fly with inop equipment if it is (quoting the reg)

(i) Part of the VFR-day type certification instruments and equipment prescribed in the applicable airworthiness regulations under which the aircraft was type certificated;
Carb heat is not
(ii) Indicated as required on the aircraft's equipment list, or on the Kinds of Operations Equipment List for the kind of flight operation being conducted;
carb heat is not
(iii) Required by § 91.205 or any other rule of this part for the specific kind of flight operation being conducted; or
Carb heat is not
(iv) Required to be operational by an airworthiness directive;
Carb heat is not

91.205, the "Tiny Rule Given Giant Status by Poor Ground Instruction" isn't even in first position, but you choose to skip the one which is.

I guess those who follow rules follow them and those who don't try to make up reasons they don't have to.

Carb heat does not meet the requirements of either regulation.

 

[MauleSkinner]

(i) Part of the VFR-day type certification instruments and equipment prescribed in the applicable airworthiness regulations under which the aircraft was type certificated;
Carb heat is not

Carb heat does not meet the requirements of either regulation.

Can you provide documentation to show that carb heat is not part of the manufacturer’s compliance with the CAR3 equivalent of 23.2415?

 

[RussR]

Carb heat does not meet the requirements of either regulation.

????

@eetrojan 's post #19 shows an excerpt from a Cessna 172P POH's Equipment List, showing the Carb Heat as a "R" item, i.e. REQUIRED. The Cessna 172M POH has the same (the aircraft the OP is talking about).

That pretty clearly meets @midlifeflyer 's list for #2:

(ii) Indicated as required on the aircraft's equipment list, or on the Kinds of Operations Equipment List for the kind of flight operation being conducted;

That seems about as black-and-white as it gets.

 

[midlifeflyer]

????

@eetrojan 's post #19 shows an excerpt from a Cessna 172P POH's Equipment List, showing the Carb Heat as a "R" item, i.e. REQUIRED. The Cessna 172M POH has the same (the aircraft the OP is talking about).

That pretty clearly meets @midlifeflyer 's list for #2:

(ii) Indicated as required on the aircraft's equipment list, or on the Kinds of Operations Equipment List for the kind of flight operation being conducted;

That seems about as black-and-white as it gets.

It's not my list. It's the FAA's

Tom already answered (ii) - a 1975 172 does not have an "equipment list" with items marked as required, operational, etc like in the more modern POH.

He hasn't answered @MauleSkinner's question about his documentary basis for saying

Carburetor Air Preheat Controls. Separate controls shall be provided to regulate the temperature of the carburetor air for each engine [CAR 3.634]​

does not require carb heat under Test #1

(i) Part of the VFR-day type certification instruments and equipment prescribed in the applicable airworthiness regulations under which the aircraft was type certificated;
​

I'll be interested to see what he comes up with. i don't think there's much reason fo further comment until we see the documentary source of his opinion.

 

[MauleSkinner]

It's not my list. It's the FAA's

Tom already answered (ii) - a 1975 172 does not have an "equipment list" with items marked as required, operational, etc like in the more modern POH.

He hasn't answered @MauleSkinner's question about his documentary basis for saying

Carburetor Air Preheat Controls. Separate controls shall be provided to regulate the temperature of the carburetor air for each engine [CAR 3.634]​

does not require carb heat under Test #1

(i) Part of the VFR-day type certification instruments and equipment prescribed in the applicable airworthiness regulations under which the aircraft was type certificated;
​

I'll be interested to see what he comes up with. i don't think there's much reason fo further comment until we see the documentary source of his opinion.

Thanks for coming up with the specific CAR reference.

 

[RussR]

It's not my list. It's the FAA's

Tom already answered (ii) - a 1975 172 does not have an "equipment list" with items marked as required, operational, etc like in the more modern POH.

Au contraire!

Here is an example 172M Equipment List from a quick search online (a flying club's scan). Looks like a required item to me. Item E93-R, R for required.

 

[midlifeflyer]

Au contraire!

Here is an example 172M Equipment List from a quick search online (a flying club's scan). Looks like a required item to me. Item E93-R, R for required.

View attachment 66301

Cool!

 

[midlifeflyer]

Thanks for coming up with the specific CAR reference.

For those interested., the FAA has a website with some (emphasize some) historical CAR stuff. I suspect it's mostly geared to the airworthiness things since those are the most likely to be relevant today.

Web Civil Air Regulations.

 

[Kritchlow]

There’s legality, and than there is good practice.

I find carb heat to be a safety of flight item. I would not fly with it broken.

 

[MauleSkinner]

For those interested., the FAA has a website with some (emphasize some) historical CAR stuff. I suspect it's mostly geared to the airworthiness things since those are the most likely to be relevant today.

Web Civil Air Regulations.

Thanks...the link from the FAA.gov regulatory page has been under construction for several months.

 

[midlifeflyer]

Thanks...the link from the FAA.gov regulatory page has been under construction for several months.

Yeah, this is an older database. Actually CAR3 has more on the subject than that one paragraph:

§ 3.606 Induction system de-icing and antiicing provisions. The engine air induction system shall incorporate means for the prevention and elimination of ice accumulations in accordance with the provisions in this section. It shall be demonstrated that compliance with the provisions outlined in the following paragraphs can be accomplished when the airplane is operating in air at a temperature of 30° F, when the air is free of visible moisture.

(a) Airplanes equipped with sea level engines employing conventional venturi carburetors shall be provided with a preheater capable of providing a heat rise of 90° F. when the engine is operating at 75 percent of its maximum continuous power.
(b) Airplanes equipped with altitude engines employing conventional venturi carburetors shall be provided with a preheater capable of providing a heat rise of 120° F. when the engine is operating at 75 percent of its maximum continuous power.
(c) Airplanes equipped with altitude engines employing carburetors which embody features tending to reduce the possibility of ice formation shall be provided with a preheater capable of providing a heat rise of 100° F. when the engine is operating at 60 percent of its maximum continuous power. However, the preheater need not provide a heat rise in excess of 40°F. if a fluid de-icing system complying with the provisions of §§ 3.607- 3.609 is also installed.​

 

[MauleSkinner]

There’s legality, and than there is good practice.

I find carb heat to be a safety of flight item. I would not fly with it broken.

The real issue to me is that while there are pilots who may not see carb heat as a safety of flight item, there are very few people who can determine the certification portion of 91.213(d)...even people with Tom's experience can easily miss it.

 

[Tom-D]

The real issue to me is that while there are pilots who may not see carb heat as a safety of flight item, there are very few people who can determine the certification portion of 91.213(d)...even people with Tom's experience can easily miss it.

I believe that many here do not believe aircraft be altered and still be considered airworthy 91.213 gives this authorization, The type certificate, or type design has nothing to do with it.
When you use 91.213 to alter, and do it IAW the rules You have in fact temporarily changed the design of the aircraft.
You must comply with 91.205 and carry those listed items, Carb heat is not one of the listed items.
So you can in fact use 91.213 to disable it.

Simply because of the first para of 91.213
91.213 Inoperative instruments and equipment.
(a) Except as provided in paragraph (d) of this section, no person may take off an aircraft with inoperative instruments or equipment installed unless the following conditions are met:

(1) An approved Minimum Equipment List exists for that aircraft.

(2) The aircraft has within it a letter of authorization, issued by the responsible Flight Standards office, authorizing operation of the aircraft under the Minimum Equipment List. The letter of authorization may be obtained by written request of the airworthiness certificate holder. The Minimum Equipment List and the letter of authorization constitute a supplemental type certificate for the aircraft.
If the aircraft doesn't have this, you must treat as if this applies:

(d) Except for operations conducted in accordance with paragraph (a) or (c) of this section, a person may takeoff an aircraft in operations conducted under this part with inoperative instruments and equipment without an approved Minimum Equipment List provided.

Many folks forget you can't use a MEL unless it has been approved for that aircraft. unless a 172 has been or is being used in part 135 it will not have one.

to recap:
91.213 does give us the authority to alter the type design of aircraft, only certain people can do it, and only some equipment can be disabled.
Most aircraft with un-working equipment, never get the paper to make them legal. most owners will defer maintenance until the annual, with no authorization to do so.

 

[MauleSkinner]

I believe that many here do not believe aircraft be altered and still be considered airworthy 91.213 gives this authorization, The type certificate, or type design has nothing to do with it.
When you use 91.213 to alter, and do it IAW the rules You have in fact temporarily changed the design of the aircraft.
You must comply with 91.205 and carry those listed items, Carb heat is not one of the listed items.
So you can in fact use 91.213 to disable it.

Simply because of the first para of 91.213
91.213 Inoperative instruments and equipment.
(a) Except as provided in paragraph (d) of this section, no person may take off an aircraft with inoperative instruments or equipment installed unless the following conditions are met:

(1) An approved Minimum Equipment List exists for that aircraft.

(2) The aircraft has within it a letter of authorization, issued by the responsible Flight Standards office, authorizing operation of the aircraft under the Minimum Equipment List. The letter of authorization may be obtained by written request of the airworthiness certificate holder. The Minimum Equipment List and the letter of authorization constitute a supplemental type certificate for the aircraft.
If the aircraft doesn't have this, you must treat as if this applies:

(d) Except for operations conducted in accordance with paragraph (a) or (c) of this section, a person may takeoff an aircraft in operations conducted under this part with inoperative instruments and equipment without an approved Minimum Equipment List provided.

Many folks forget you can't use a MEL unless it has been approved for that aircraft. unless a 172 has been or is being used in part 135 it will not have one.

to recap:
91.213 does give us the authority to alter the type design of aircraft, only certain people can do it, and only some equipment can be disabled.
Most aircraft with un-working equipment, never get the paper to make them legal. most owners will defer maintenance until the annual, with no authorization to do so.

Exactly...but as you said, this falls under 91.213(d), which clearly doesn’t give anyone the authority to alter the type design of the aircraft.

And even if it did have an MEL, that MEL would not include he ability to defer carb heat.

 

[Tom-D]

Lack of carb heat is a hazard to the aircraft

That is a personal opinion. not a fact in consideration.
The pilot has a right to consider the conditions of the flight and make their own decision.

 

[Tom-D]

Exactly...but as you said, this falls under 91.213(d),which clearly doesn’t give anyone the authority to alter the type design of the aircraft.

Yes in fact it does.
a person may takeoff an aircraft in operations conducted under this part with inoperative instruments and equipment without an approved Minimum Equipment List provided—

Follow the provisions and you will alter the type design temporary.

Simply because if the aircraft couldn't be altered, we couldn't use this rule.

 

[MauleSkinner]

Yes in fact it does.
a person may takeoff an aircraft in operations conducted under this part with inoperative instruments and equipment without an approved Minimum Equipment List provided—

Follow the provisions and you will alter the type design temporary.

Simply because if the aircraft couldn't be altered, we couldn't use this rule.

Ok...probably better stated, 91.213(d) does not allow deviations from the certification requirements of, in this case, CAR3.

And as yet, you have refused to show how carb heat is not part of the CARs quoted.

 

[Silvaire]

Why is this even being discussed? You’re doing your pre-takeoff checks and the carb heat knob comes out of the panel. What’s the question here? You don’t even know what’s broken down there, the whole air box could be busted off for all you know.

Where’s my face palm emoji?

 

[Tom-D]

Ok...probably better stated, 91.213(d) does not allow deviations from the certification requirements of, in this case, CAR3.

And as yet, you have refused to show how carb heat is not part of the CARs quoted.

Certification does not have anything to do with 91.213
Certification rules set the standard to keep the aircraft airworthy.
Using 91.213 you are modifying the the type design of the aircraft to be able to operate the aircraft while it does not meet its type design.
If you couldn't use 91.213 to modify the aircraft, you would never be able to operate the aircraft with any piece of equipment Inop. You'd be required to get a field approval or a Ferry permit every time anything failed.
An other way to put this is, 91.213 allows you to operate your aircraft under certain circumstances while it does not meet its type design. IOWs it alters the type design to allow this.
This is why the Administrator has placed this in 91.213

An aircraft with inoperative instruments or equipment as provided in paragraph (d) of this section is considered to be in a properly altered condition acceptable to the Administrator.

If it didn't alter the type design, what did it alter? The Administrator thinks it altered some thing,, What?

 

[Dan Thomas]

An aircraft with inoperative instruments or equipment as provided in paragraph (d) of this section is considered to be in a properly altered condition acceptable to the Administrator.

If it didn't alter the type design, what did it alter? The Administrator thinks it altered some thing,, What?

Like I said, that section allows you to defer stuff that isn't needed for the proposed flight, and the "stuff" is stuff that was not part of the type design. Lots of airplanes were built without heading or attitude indicators, or transponders, or even comms, or nav and landing lights or stall warning systems. Most were "Optional" items that permitted flight at night or in IMC or in Class B or C or D airspace. Carburetor heat WAS part of the type design and the TC reflects that, and the equipment list shows it.

We had a 1969 172L that had an equipment list, and such lists were around before that. Like Cessna says in their TCDS, for airplanes before the 172E, refer to the other documents specified for the "required" stuff. And "required" means installed and operating. No deferring or placarding as inoperable. Fuel gauges are another example of such required things, along with airspeed, altimeter, engine gauges and the like. See FAR 91.205. It's reflecting the requirments of FAR 23.1303 and 23.1305.

 

[Dan Thomas]

The real issue to me is that while there are pilots who may not see carb heat as a safety of flight item....

The real issue is that too many pilots don't understand the physics, risks and reality of carb ice, and so they think the carb heat is unimportant. When the engine starts stumbling they just open the throttle further and it clears up; it was icing up but the increased airflow cleared (sublimated) it. If the temperature had been a little lower, or the humidity (dewpoint) a little higher, they'd be out of luck. AOPA says that carb ice is one of the leading causes of engine failure, and airplanes that crash are often found to have absolutely nothing wrong with the engine or fuel supply that would have stopped it, but the atmospheric conditions at the time were conducive to carb icing. The ice, of course, is long gone by the time the investigators get there.

 

[MauleSkinner]

Certification does not have anything to do with 91.213

Really? So what is the part about “the applicable airworthiness regulations under which the aircraft was type certificated” saying?

 

[JAWS]

That is a personal opinion. not a fact in consideration.
The pilot has a right to consider the conditions of the flight and make their own decision.

My opinion based on CAR3, FAR23 and the NTSB report I provided.

As I said before, pilots (and mechanics) are supposed to make decisions, but they are also supposed to make informed decisions and must also accept the sanctions that come with making an error in those decisions.

This is an excellent discussion for all. This is a poorly taught aspect of being a pilot and a maintainer. The OP did an excellent job and should be commended for bringing this here to be discussed.

PS I forgot CAR523 as well!

 

[JAWS]

There are rules to follow. 91.213 says that you can not remove equipment that are required by 91.205.

carb heat is not one of those required by 91.205

Also doesn't say you need a seat. Or a propeller. Or a rudder. Or a left wing. So I guess those are all OK to defer as well?