Shadrach Posted August 30, 2019 Report Share Posted August 30, 2019 (edited) 5 hours ago, PT20J said: Here is the rub, I think. If anyone performs maintenance or repair on a certificated aircraft or component, I believe that they have to be authorized to perform such work and they have to certify that after completing the work the aircraft or component is airworthy. The airworthiness certification is by signature in the logbook, or in the case of a component, an 8130. If you open an instrument, you need to be able to test it to certify it is airworthy after you put it back together. Pilots are not authorized to open instruments and don’t likely have the equipment to verify it after the work. Skip I’m in total agreement with everything that you said above. However there are others in this thread that are suggesting that an A&P/IA, a certified professional that the FAA has deemed capable and competent to remove, overhaul, reinstall and return an engine to service, cannot legally change the elbow fitting to a straight fitting on the back of an AI or open an instrument for any reason whether it be bezel and glass of a VSI for cleaning and reinstallation or something else. I have asked those individuals to show me the reg that specifies their statements as law. None have produced such a regulation. In lieu of such a reg, I’ve gotten to learn a great deal about different members credentials and backgrounds and how long they’ve been experts in their field... some of which I’ve only had the pleasure of reading a few or ten times before in other threads... Edited August 30, 2019 by Shadrach 1 Quote Link to comment Share on other sites More sharing options...
Bob Weber Posted August 30, 2019 Report Share Posted August 30, 2019 Replacing the fitting on the back of an ATT gyro is most certainly legal for an A/P to accomplish, just not disassembling an instrument. They cannot do that legally without maint man, ratings, and equipment. End of discussion. 1 Quote Link to comment Share on other sites More sharing options...
GeeBee Posted August 30, 2019 Report Share Posted August 30, 2019 41 minutes ago, Shadrach said: I’m in total agreement with everything that you said above. However there are others in this thread that are suggesting that an A&P/IA, a certified professional that the FAA has deemed capable and competent to remove, overhaul, reinstall and return an engine to service, cannot legally change the elbow fitting to a straight fitting on the back of an AI or open an instrument for any reason whether it be bezel and glass of a VSI for cleaning and reinstallation or something else. I have asked those individuals to show me the reg the specifies their statements as law. None have produced such a regulation. In lieu of such a reg, I’ve gotten to learn a great deal about different members credentials and backgrounds and how long they’ve been experts in their field... some of which I’ve only had the pleasure of reading a few or ten times before in other threads... FAR 65.81(a) Need I say more? 65.81 — General privileges and limitations. (a) A certificated mechanic may perform or supervise the maintenance, preventive maintenance or alteration of an aircraft or appliance, or a part thereof, for which he is rated (but excluding major repairs to, and major alterations of, propellers, and any repair to, or alteration of, instruments), and may perform additional duties in accordance with §§65.85, 65.87, and 65.95. However, he may not supervise the maintenance, preventive maintenance, or alteration of, or approve and return to service, any aircraft or appliance, or part thereof, for which he is rated unless he has satisfactorily performed the work concerned at an earlier date. If he has not so performed that work at an earlier date, he may show his ability to do it by performing it to the satisfaction of the Administrator or under the direct supervision of a certificated and appropriately rated mechanic, or a certificated repairman, who has had previous experience in the specific operation concerned. And yes, if you change the fitting on the back of an instrument which is not approved by the manufacturer in its STC, or ICA it is an alteration and cannot be done by an A&P 1 Quote Link to comment Share on other sites More sharing options...
David_H Posted August 30, 2019 Report Share Posted August 30, 2019 1 hour ago, GeeBee said: FAR 65.81(a) Need I say more? 65.81 — General privileges and limitations. (a) A certificated mechanic may perform or supervise the maintenance, preventive maintenance or alteration of an aircraft or appliance, or a part thereof, for which he is rated (but excluding major repairs to, and major alterations of, propellers, and any repair to, or alteration of, instruments), and may perform additional duties in accordance with §§65.85, 65.87, and 65.95. However, he may not supervise the maintenance, preventive maintenance, or alteration of, or approve and return to service, any aircraft or appliance, or part thereof, for which he is rated unless he has satisfactorily performed the work concerned at an earlier date. If he has not so performed that work at an earlier date, he may show his ability to do it by performing it to the satisfaction of the Administrator or under the direct supervision of a certificated and appropriately rated mechanic, or a certificated repairman, who has had previous experience in the specific operation concerned. And yes, if you change the fitting on the back of an instrument which is not approved by the manufacturer in its STC, or ICA it is an alteration and cannot be done by an A&P For a litmus test, one could ask a repair station if they need the fittings to repair a gyro instrument. Just to be completely certain, one might as well ask if they also need the Pitot tube as well. This could give some insight into what is considered an instrument repair. The instrument is connected to the pitot-static system via a fitting. The fitting is not a part of the instrument. 2 Quote Link to comment Share on other sites More sharing options...
EricJ Posted August 30, 2019 Report Share Posted August 30, 2019 GeeBee beat me to it, and I'll add that, having JUST taken my written and oral and practical exams and gotten my temporary airframe maintenance cert (i.e., the A in A&P), I can tell you that this is a study and question topic for both the written and oral exams. The study questions in the ASA and Jeppesen study materials look like this: Who is authorized to repair an aircraft instrument? 1. A certified mechanic with an airframe rating. 2. A certificated repairman with an airframe rating. 3. A certificated repair station approved for that class instrument. 4. A certificated airframe repair station. A. 1, 2, 3, and 4 B. 3 and 4 C. 3 The answer is C. A certificated mechanic with airframe and powerplant ratings may: A. perform minor repairs to aircraft instruments. B. perform minor repairs and and minor alterations to aircraft instruments. C. not perform repairs to aircraft instruments. The answer is C. Which of the following instrument discrepancies could be corrected by an aviation mechanic? 1. Red line missing. 2. Case leaking. 3. Glass cracked. 4. Mounting screws loose. 5. Case paint chipped. 6. Leaking at line B nut. 7. Will not adjust. 8. Fogged. A. 1, 4, 6 B. 3, 4, 5, 6 C. 1, 4, 5, 6 The answer is C. Adding the red line (for 1) does not involve removing the glass. It is putting a red mark on the surface of the glass and a white slippage mark on the outside of the glass and frame. Removing the glass, for cleaning or any other purpose, is very clearly outside of the scope of the authority of an A&P or an IA. What the A&P or IA can do for you is inspect it and determine that it needs to go to a certified repair station. Note that "Fogged" is not part of the correct answer in the last one. This got drilled into us pretty hard...instruments cannot be opened or repaired. An A&P can do a static leak check after reinstallation (*not* a recert, just the leak check), and can remove and install and inspect instruments, but that's pretty much it. Everything else requires the proper repair station authority. What the hangar elves may do during the night should always remain a mystery to mere mortals, but this is what is currently being taught and tested for new A&Ps. 3 1 Quote Link to comment Share on other sites More sharing options...
GeeBee Posted August 30, 2019 Report Share Posted August 30, 2019 "The instrument is connected to the pitot-static system via a fitting. The fitting is not a part of the instrument' Not always true. Some instruments have their own propriety connector (Aspen for instance) the use of which is demanded in the install manual. If there is no requirement in the install manual, the STC or the ICA then AC43.13 applies. It is not always cut and dry. Equally so, when you crack open the pitot static system, an honest return to service statement would be almost impossible without a pitot static check which would require a someone with a repairman certificate. Quote Link to comment Share on other sites More sharing options...
David_H Posted August 30, 2019 Report Share Posted August 30, 2019 (edited) Having a proprietary connector specified in an install manual... still makes it a connector. The type or brand of instrument is irrelevant. The installation manual is... an "Installation Manual" meant to provide installation instruction (not repair instruction.) An authorized instrument repair requires a different manual because it fulfills a different purpose. For IFR flight, a Pitot-Static check is required every 24 months. The Pitot-Static check requirement is not present for a return to service statement for VFR conditions. The fact that we are discussing IFR vs VFR Pitot-Static check requirements is also an indicator that a connector is part of the Pitot-Static system... not part of the instrument. Edited August 30, 2019 by David_H Quote Link to comment Share on other sites More sharing options...
GeeBee Posted August 30, 2019 Report Share Posted August 30, 2019 A pitot static check is required for a return to service statement if you have a mode C encoder involved in your system. If you are going to fly VFR in Class B, Class B umbrella or Class C airspace the two systems are inexorably linked. You would be hard pressed to find a repair shop that will just do a transponder check these days because AC43-6 requires a static leak down test when working on the encoder. Also now, with ADS-B the systems are co-existent. If your GPS altitude and your mode C out from your static system are significantly different, or you report an altitude while in controlled airspace that differs from your mode C output (again from your static system), you will get a "cease operations" letter from the FAA prohibiting you from operating in ADS-B required airspace and to cease broadcasting transponder signal until repair is made, certified and a PAPR flight verifies correct operation. Quote Link to comment Share on other sites More sharing options...
Shadrach Posted August 30, 2019 Report Share Posted August 30, 2019 2 hours ago, David_H said: For a litmus test, one could ask a repair station if they need the fittings to repair a gyro instrument. Just to be completely certain, one might as well ask if they also need the Pitot tube as well. This could give some insight into what is considered an instrument repair. The instrument is connected to the pitot-static system via a fitting. The fitting is not a part of the instrument. I think the prudent thing to do is to ship them the whole plane. 1 Quote Link to comment Share on other sites More sharing options...
Shadrach Posted August 30, 2019 Report Share Posted August 30, 2019 2 hours ago, EricJ said: GeeBee beat me to it, and I'll add that, having JUST taken my written and oral and practical exams and gotten my temporary airframe maintenance cert (i.e., the A in A&P), I can tell you that this is a study and question topic for both the written and oral exams. The study questions in the ASA and Jeppesen study materials look like this: Who is authorized to repair an aircraft instrument? 1. A certified mechanic with an airframe rating. 2. A certificated repairman with an airframe rating. 3. A certificated repair station approved for that class instrument. 4. A certificated airframe repair station. A. 1, 2, 3, and 4 B. 3 and 4 C. 3 The answer is C. A certificated mechanic with airframe and powerplant ratings may: A. perform minor repairs to aircraft instruments. B. perform minor repairs and and minor alterations to aircraft instruments. C. not perform repairs to aircraft instruments. The answer is C. Which of the following instrument discrepancies could be corrected by an aviation mechanic? 1. Red line missing. 2. Case leaking. 3. Glass cracked. 4. Mounting screws loose. 5. Case paint chipped. 6. Leaking at line B nut. 7. Will not adjust. 8. Fogged. A. 1, 4, 6 B. 3, 4, 5, 6 C. 1, 4, 5, 6 The answer is C. Adding the red line (for 1) does not involve removing the glass. It is putting a red mark on the surface of the glass and a white slippage mark on the outside of the glass and frame. Removing the glass, for cleaning or any other purpose, is very clearly outside of the scope of the authority of an A&P or an IA. What the A&P or IA can do for you is inspect it and determine that it needs to go to a certified repair station. Note that "Fogged" is not part of the correct answer in the last one. This got drilled into us pretty hard...instruments cannot be opened or repaired. An A&P can do a static leak check after reinstallation (*not* a recert, just the leak check), and can remove and install and inspect instruments, but that's pretty much it. Everything else requires the proper repair station authority. What the hangar elves may do during the night should always remain a mystery to mere mortals, but this is what is currently being taught and tested for new A&Ps. Finally! We have an answer. Thank you Eric 1 Quote Link to comment Share on other sites More sharing options...
Shadrach Posted August 30, 2019 Report Share Posted August 30, 2019 2 hours ago, GeeBee said: "The instrument is connected to the pitot-static system via a fitting. The fitting is not a part of the instrument' Not always true. Some instruments have their own propriety connector (Aspen for instance) the use of which is demanded in the install manual. If there is no requirement in the install manual, the STC or the ICA then AC43.13 applies. It is not always cut and dry. Equally so, when you crack open the pitot static system, an honest return to service statement would be almost impossible without a pitot static check which would require a someone with a repairman certificate. So an “honest” return to service after a vacuum pump is replaced would require a pitot static check by a someone with a repairman cert? Quote Link to comment Share on other sites More sharing options...
Shadrach Posted August 30, 2019 Report Share Posted August 30, 2019 22 hours ago, GeeBee said: Replace the fitting on the back? That's a repair. 5 hours ago, cliffy said: Changing a fitting on the back of the instrument is "maintenance" pure and simple 5 hours ago, Bob Weber said: Replacing the fitting on the back of an ATT gyro is most certainly legal for an A/P to accomplish, just not disassembling an instrument. Two yes and one no. This is the reason I asked for the reg when someone says this is legal or that’s not legal. You gentleman might think I was being deliberately disagreeable but I’m was not. I wanted to see the language. Eric was kind enough to show a question from the FAA A&P written which makes clear the FAA’s definition of major and minor repair (it’s obvious that defogging is not something the feds think should be done in the field) That’s good enough for me. Changing fittings shall remain.... 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted August 30, 2019 Report Share Posted August 30, 2019 +1 for Ross asking the question... Ross often asks deeper and technically challenging questions, ...and that can be difficult to sound friendly at the same time.... +1 for Cliffy’s wealth of technical knowledge... holy cow depth and width and experience all at the same time... + great sentence structure and easy to read and understand... +1 for GB and Bob Weber for supporting the challenging technical discussion... +1 for Eric sharing what he is training on... I almost got the right answer... I have learned a lot about instruments and their service here... and explanations for why their glass has become dirty and why an rpm marking change was applied to the surface of my M20C’s tach... Thanks and best regards, -a- Quote Link to comment Share on other sites More sharing options...
GeeBee Posted August 31, 2019 Report Share Posted August 31, 2019 1 hour ago, Shadrach said: So an “honest” return to service after a vacuum pump is replaced would require a pitot static check by a someone with a repairman cert? Do you crack open the pitot static system when you replace a vacuum pump? 1 1 Quote Link to comment Share on other sites More sharing options...
Shadrach Posted August 31, 2019 Report Share Posted August 31, 2019 1 hour ago, GeeBee said: Do you crack open the pitot static system when you replace a vacuum pump? Touché. Total brain fart on my part... Quote Link to comment Share on other sites More sharing options...
PT20J Posted August 31, 2019 Report Share Posted August 31, 2019 I think Ross’ original question where he referenced a mechanic stating that any used part required an 8130 is actually more interesting. You A&Ps can correct me if I’m wrong, but it’s my understanding that the issue is that the logbook signoff attests that the aircraft is airworthy and therefore the installed part must be airworthy. If it comes with an 8130, someone else has attested to its airworthiness. In the absence of an 8130, the A&P is on the hook to determine if it is airworthy. Whether a mechanic is willing to install a used part with no 8130 depends on his ability and comfort with that determination. I had a bad WX 900 display unit and replaced it with one I bought on eBay with no 8130. My A&P/IA had no issue looking at it and signing it off. But suppose I similarly replaced my KC 191 autopilot computer with an eBay unit - would he be as comfortable approving it knowing I fly it IFR and it’s a more complex and safety-critical piece of equipment, and he has no way to bench test it? Skip 2 Quote Link to comment Share on other sites More sharing options...
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