Another INOP Equipment Thread - EGT/CHT

Skid

Pre-takeoff checklist
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Skid
Still trying to get a good understanding on how to handle inoperative equipment so its not so cryptic every time I face the situation. This time flying a C172S G1000 with an inop EGT and CHT (red X's over all 8 displays - 4 EGTS, 4 CHTS)*.

*I was still receiving RPM, fuel, oil information so I presume the GEA 71 didn't completely fail?

In any case, following 91.213(d) it doesn't look like EGTs or CHTs are required. Looking at a random POH for a C172S they are listed as standard equipment, so my understanding means I can "deactivate and placard" them.

My confusion is when this comes to the G1000, not sure how I would go about deactivating the EGT/CHT (if its even possible). There's no dedicated breaker to my understanding so this makes me believe this is impossible without physically removing each of the sensors (this seems a bit over the top but maybe not). If there were breakers or they were actually removed in some way, would the "Red X's" replace the required INOP tag?

Just hoping to get a more complete understanding of it all. Thanks
 
91.213(d)(3)
(ii) Deactivated and placarded “Inoperative.” If deactivation of the inoperative instrument or equipment involves maintenance, it must be accomplished and recorded in accordance with part 43 of this chapter; and


43.3
a) Except as provided in this section and §43.17, no person may maintain, rebuild, alter, or perform preventive maintenance on an aircraft, airframe, aircraft engine, propeller, appliance, or component part to which this part applies.

b) The holder of a mechanic certificate may perform maintenance, preventive maintenance, and alterations as provided in Part 65 of this chapter

g) Except for holders of a sport pilot certificate, the holder of a pilot certificate issued under part 61 may perform preventive maintenance on any aircraft owned or operated by that pilot which is not used under part 121, 129, or 135 of this chapter. The holder of a sport pilot certificate may perform preventive maintenance on an aircraft owned or operated by that pilot and issued a special airworthiness certificate in the light-sport category.


1.1 Definitions

Maintenance means inspection, overhaul, repair, preservation, and the replacement of parts, but excludes preventative maintenance.

Preventive maintenance means simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations.



Appendix H

(c) Preventive maintenance

Preventive maintenance is limited to the following work, provided it does not involve complex assembly operations:

(1) Removal, installation, and repair of landing gear tires.

(2) Replacing elastic shock absorber cords on landing gear.

(3) Servicing landing gear shock struts by adding oil, air, or both.

(4) Servicing landing gear wheel bearings, such as cleaning and greasing.

(5) Replacing defective safety wiring or cotter keys.

(6) Lubrication not requiring disassembly other than removal of nonstructural items such as cover plates, cowlings, and fairings.

(7) Making simple fabric patches not requiring rib stitching or the removal of structural parts or control surfaces. In the case of balloons, the making of small fabric repairs to envelopes (as defined in, and in accordance with, the balloon manufacturers' instructions) not requiring load tape repair or replacement.

(8) Replenishing hydraulic fluid in the hydraulic reservoir.

(9) Refinishing decorative coating of fuselage, balloon baskets, wings tail group surfaces (excluding balanced control surfaces), fairings, cowlings, landing gear, cabin, or cockpit interior when removal or disassembly of any primary structure or operating system is not required.

(10) Applying preservative or protective material to components where no disassembly of any primary structure or operating system is involved and where such coating is not prohibited or is not contrary to good practices.

(11) Repairing upholstery and decorative furnishings of the cabin, cockpit, or balloon basket interior when the repairing does not require disassembly of any primary structure or operating system or interfere with an operating system or affect the primary structure of the aircraft.

(12) Making small simple repairs to fairings, nonstructural cover plates, cowlings, and small patches and reinforcements not changing the contour so as to interfere with proper air flow.

(13) Replacing side windows where that work does not interfere with the structure or any operating system such as controls, electrical equipment, etc.

(14) Replacing safety belts.

(15) Replacing seats or seat parts with replacement parts approved for the aircraft, not involving disassembly of any primary structure or operating system.

(16) Trouble shooting and repairing broken circuits in landing light wiring circuits.

(17) Replacing bulbs, reflectors, and lenses of position and landing lights.

(18) Replacing wheels and skis where no weight and balance computation is involved.

(19) Replacing any cowling not requiring removal of the propeller or disconnection of flight controls.

(20) Replacing or cleaning spark plugs and setting of spark plug gap clearance.

(21) Replacing any hose connection except hydraulic connections.

(22) Replacing prefabricated fuel lines.

(23) Cleaning or replacing fuel and oil strainers or filter elements.

(24) Replacing and servicing batteries.

(25) Cleaning of balloon burner pilot and main nozzles in accordance with the balloon manufacturer's instructions.

(26) Replacement or adjustment of nonstructural standard fasteners incidental to operations.

(27) The interchange of balloon baskets and burners on envelopes when the basket or burner is designated as interchangeable in the balloon type certificate data and the baskets and burners are specifically designed for quick removal and installation.

(28) The installations of anti-misfueling devices to reduce the diameter of fuel tank filler openings provided the specific device has been made a part of the aircraft type certificiate data by the aircraft manufacturer, the aircraft manufacturer has provided FAA-approved instructions for installation of the specific device, and installation does not involve the disassembly of the existing tank filler opening.

(29) Removing, checking, and replacing magnetic chip detectors.

(30) The inspection and maintenance tasks prescribed and specifically identified as preventive maintenance in a primary category aircraft type certificate or supplemental type certificate holder's approved special inspection and preventive maintenance program when accomplished on a primary category aircraft provided:

(i) They are performed by the holder of at least a private pilot certificate issued under part 61 who is the registered owner (including co-owners) of the affected aircraft and who holds a certificate of competency for the affected aircraft (1) issued by a school approved under §147.21(e) of this chapter; (2) issued by the holder of the production certificate for that primary category aircraft that has a special training program approved under §21.24 of this subchapter; or (3) issued by another entity that has a course approved by the Administrator; and

(ii) The inspections and maintenance tasks are performed in accordance with instructions contained by the special inspection and preventive maintenance program approved as part of the aircraft's type design or supplemental type design.

(31) Removing and replacing self-contained, front instrument panel-mounted navigation and communication devices that employ tray-mounted connectors that connect the unit when the unit is installed into the instrument panel, (excluding automatic flight control systems, transponders, and microwave frequency distance measuring equipment (DME)). The approved unit must be designed to be readily and repeatedly removed and replaced, and pertinent instructions must be provided. Prior to the unit's intended use, and operational check must be performed in accordance with the applicable sections of part 91 of this chapter.

(32) Updating self-contained, front instrument panel-mounted Air Traffic Control (ATC) navigational software data bases (excluding those of automatic flight control systems, transponders, and microwave frequency distance measuring equipment (DME)) provided no disassembly of the unit is required and pertinent instructions are provided. Prior to the unit's intended use, an operational check must be performed in accordance with applicable sections of part 91 of this chapter.
 
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How about a label on the G1000 that reads: “CHT AND EGT READOUTS INOP”.

As an aside, not sure how helpful it is to just copy and paste large blocks of text, much of which is not pertinent to the question being asked.

As a further aside, C172’s have flown forever without EGT or CHT info, so as a practical matter it doesn’t seem like a big deal.
 
How about a label on the G1000 that reads: “CHT AND EGT READOUTS INOP”.

As an aside, not sure how helpful it is to just copy and paste large blocks of text, much of which is not pertinent to the question being asked.

As a further aside, C172’s have flown forever without EGT or CHT info, so as a practical matter it doesn’t seem like a big deal.

Actually all of that was pertinent. If the aircraft does not have an MEL, the inoperative equipment must be removed or deactivated by a mechanic unless it is a tray mounted radio as provided in 31 of the preventative maint list.

A pilot May not ust put a placard on it. Doing so is the equivalent of putting a sign on your panel that says “FAA inspector, I am illegal”.

Read 91.213.
 
Actually all of that was pertinent. If the aircraft does not have an MEL, the inoperative equipment must be removed or deactivated by a mechanic unless it is a tray mounted radio as provided in 31 of the preventative maint list.

A pilot May not ust put a placard on it. Doing so is the equivalent of putting a sign on your panel that says “FAA inspector, I am illegal”.

Read 91.213.

It is a try mounted radio

As a further aside, C172’s have flown forever without EGT or CHT info, so as a practical matter it doesn’t seem like a big deal.

https://www.pilotsofamerica.com/community/threads/bad-fuel-hot-jug-and-climbing-cht.110755/

I don't mind flying without, I just don't like night, IMC, or flying over less than friendly terrain without
 
His plane is illegal to fly.

43.3
a) Except as provided in this section and §43.17, no person may maintain, rebuild, alter, or perform preventive maintenance on an aircraft, airframe, aircraft engine, propeller, appliance, or component part to which this part applies.


3) The inoperative instruments and equipment are--
(i) Removed from the aircraft, the cockpit control placarded, and the maintenance recorded in accordance with Sec. 43.9 of this chapter; or
(ii) Deactivated and placarded "Inoperative." If deactivation of the inoperative instrument or equipment involves maintenance, it must be accomplished and recorded in accordance with part 43 of this chapter; and
(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.
 
Still trying to get a good understanding on how to handle inoperative equipment so its not so cryptic every time I face the situation. This time flying a C172S G1000 with an inop EGT and CHT (red X's over all 8 displays - 4 EGTS, 4 CHTS)*.

*I was still receiving RPM, fuel, oil information so I presume the GEA 71 didn't completely fail?

In any case, following 91.213(d) it doesn't look like EGTs or CHTs are required. Looking at a random POH for a C172S they are listed as standard equipment, so my understanding means I can "deactivate and placard" them.

My confusion is when this comes to the G1000, not sure how I would go about deactivating the EGT/CHT (if its even possible). There's no dedicated breaker to my understanding so this makes me believe this is impossible without physically removing each of the sensors (this seems a bit over the top but maybe not). If there were breakers or they were actually removed in some way, would the "Red X's" replace the required INOP tag?

Just hoping to get a more complete understanding of it all. Thanks

I work on G1000 equipped Kingairs.

The G1000 is an integrated avionics system. It looks really nice and usually operates well, but it does have some unique limits. Such as the GEA. If one portion of the GEA quits, the entire thing is considered unservicable - it is not operating as designed. Having a fully operational GEA is required equipment in the POH. The red X's mean something has failed or is in the process of failing.

On the Kingair with an MEL, the GEA is not defer-able, even when one relatively minor indication goes haywire.

I do agree that the aircraft is safe. If it was a 1976 172M, it could be legal too. But with all the gee-whiz wonder of the G1000 comes a few limitations that the 172M doesn't have.

EDIT Looking deeper in the G1000 172 POH, the EGT and CHT probes are standard equipment, not required equipment. I guess you could go to the LRU reporting page on the MFD and make sure it is check marked green. Might be defer-able that way. Interesting conundrum.
 
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As a further aside, C172’s have flown forever without EGT or CHT info, so as a practical matter it doesn’t seem like a big deal.

https://www.pilotsofamerica.com/community/threads/bad-fuel-hot-jug-and-climbing-cht.110755/

I don't mind flying without, I just don't like night, IMC, or flying over less than friendly terrain without
I work on G1000 equipped Kingairs.

The G1000 is an integrated avionics system. It looks really nice and usually operates well, but it does have some unique limits. Such as the GEA. If one portion of the GEA quits, the entire thing is considered unservicable - it is not operating as designed. Having a fully operational GEA is required equipment in the POH. The red X's mean something.

I do agree that the aircraft is safe. If it was a 1976 172M, it could be legal too. But with all the gee-whiz wonder of the G1000 comes a few limitations that the 172M doesn't have.

Did not know that, so any X on a G1000 legally takes the whole G1000 out?

Damn!
 
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