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Altimeter and Transponder Check Price Gouging

How much are you paying for your 91.411 and 91.413 checks?


  • Total voters
    108
  • Poll closed .
$410 this year for full pitot, static, altimeter and transponder 2 year 91.411 and 91.413 checks including backup G5. My avionics guy brings a lot of gear to my hangar and like Walt said he has to pay to keep everything calibrated. Once he gets everything set up it takes him about 30-45 minutes to finish everything. When you factor in the condition inspection, insurance, hangar cost, 2 year IFR checks, BFRs, AVGAS locally at $5.85/gal, etc, etc it’s usually best not to think too hard about how much it all costs and more about how much fun an RV is. Yeah things have gone up over time but my RV is what keeps me sane when I need to go turn my brains inside out or just take friends up for some local cruising or lunch runs.
 
From a compliance perspective, only the primary altimeter used for IFR operations must be inspected and tested IAW FAR 91.411. The others can be placarded VFR only.
I did not know this! I'm going to print out a label and save a few hundred bucks next time. :) My next donation to VAF has now been paid for.

If you have an auto pilot that flys off of AirData from the G5 ADAHRS or something not tested you would not legally allowed to use the auto pilot for altitude hold, climbs, etc. during IFR operations.
Is there a reg that would make use of an autopilot under those circumstances illegal? Not an issue with my setup, but I would think you'd be okay so long as whatever you're doing with the autopilot complies with your clearance, as measured by your tested altimeter. Of course, what I assume and what the FARs provide may be different...

For certified aircraft, my guess is that the STC for any given autopilot requires it be connected to a tested altimeter, but who knows.
 
If the purpose of a second altimeter is redundancy, it seems logical that the backup be checked. Perhaps I'm over spending, but I don't want to get into "which is more correct" territrory,

Who wants to to call up and say:: Foet Worth Center, Busgdestroyer666, 6000ft or 63000ft, which looks right on your end?

And please lets not go down the rabbit hole of the tiebreaker being a third measurement like a non-waas GPS, an iPad or an Aviation portable,
 
If the purpose of a second altimeter is redundancy, it seems logical that the backup be checked. Perhaps I'm over spending, but I don't want to get into "which is more correct" territrory,
Of course, you only have that problem if they don’t agree. My feeling is that if my backup altimeter always reads the same as the one that’s been tested, it’s probably suitable as a backup.
 
From a compliance perspective, only the primary altimeter used for IFR operations must be inspected and tested IAW FAR 91.411. The others can be placarded VFR only. The placards need to be very clear and leave no room for accidental use. I could see this being a challenge if the Altimeters are not reading the same altitudes. It could lead to being confused when flying. If you have an auto pilot that flys off of AirData from the G5 ADAHRS or something not tested you would not legally allowed to use the auto pilot for altitude hold, climbs, etc. during IFR operations.
You may consider this open to interpretation, but any precision altimeter withing the pilots view must be checked is the FAA's (and my) view.
I will not placard a G5 for instance that is in the primary field of view of the pilot, besides why would you? Defeats the purpose.

(1) Within the preceding 24 calendar months, each static pressure system, each altimeter instrument, and each automatic pressure altitude reporting system has been tested and inspected and found to comply with appendices E and F of part 43 of this chapter;
 
Just quoted $550 for a single transponder/altimeter by the only FBO in Bloomington, IL. Any suggestions for alternatives nearby?
Thanks
 
This is a wild thread! Fun to follow. I don't see many talking about the transponder check that is required before the first flight. I am building inside of a Class B box that requires ADSB/ModeC. I can't even fly the plane for the first time without the transponder check. What do people do that are building on airports that do not have a repair station that can do the transponder check or the FBO's on the filed do not work on small GA aircraft?
The guy at LVK is actually only there 2-3 days a week. Other times, he’s on the road, with all his equipment in the back of his truck, visiting other airports. i.e., check nearby airports.
 
And please lets not go down the rabbit hole of the tiebreaker being a third measurement like a non-waas GPS, an iPad or an Aviation portable,
Hopefully everyone understands that GPS altitude - WAAS or no WAAS - is usually different than barometric altitude. This is a big deal for those of us in the mountinous west.
 
Hopefully everyone understands that GPS altitude - WAAS or no WAAS - is usually different than barometric altitude. This is a big deal for those of us in the mountinous west.
I was taught that GPS altitude helps you avoid hitting ground granite while barometric altitude helps you avoid hitting airborne aluminum. ;)
 
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Yesterday, 7 of us paid $155 each for a vfr transponder check. The shop rate is $125/hr so the extra $30 was my share of the travel expense. For the record, this service cost me $90 5 years ago.

Hi Steve,

Could you share the shop location please? My transponder check is almost due and Walt is too far...

Walt - 1.jpeg
 
You may consider this open to interpretation, but any precision altimeter withing the pilots view must be checked is the FAA's (and my) view.
I’m ready to believe you, as I'm no expert, but where do either the FAA or FARs say this? If you’re right, wouldn’t that mean that having an inop backup altimeter “within the pilot’s field of view” would prohibit IFR flight?
 
Just quoted $550 for a single transponder/altimeter by the only FBO in Bloomington, IL. Any suggestions for alternatives nearby?
Thanks
Revv aviation in Davenport Iowa (KDVN) did mine in March 2023 for $374.50.
 
I’m ready to believe you, as I'm no expert, but where do either the FAA or FARs say this? If you’re right, wouldn’t that mean that having an inop backup altimeter “within the pilot’s field of view” would prohibit IFR flight?
See my post #55 for a quote from the regs.
How you handle inoperative equipment is up to you as the operator, it has nothing to do with the certification requirements.
 
See my post #55 for a quote from the regs.
How you handle inoperative equipment is up to you as the operator, it has nothing to do with the certification requirements.
I don’t think the reg decides the question, since it applies only to IFR operations. Another way to put my question is:

Let’s say you’re in an airplane that you want to operate under IFR flight. You have a backup altimeter in your panel that is untested. Is it (a) legal to label the backup altimeter INOP and then go fly under IFR, but (b) illegal to label the backup altimeter VFR ONLY and then go fly under IFR?

If so, that probably wouldn’t be the weirdest result of applying the FARs, but it would still be fairly weird. 🤣
 
I’m ready to believe you, as I'm no expert, but where do either the FAA or FARs say this? If you’re right, wouldn’t that mean that having an inop backup altimeter “within the pilot’s field of view” would prohibit IFR flight?
See my post #55 for a quote from the regs.
How you handle inoperative equipment is up to you as the operator, it has nothing to do with the certification requirements.
I don’t think the reg decides the question, since it applies only to IFR operations. Another way to put my question is:

Let’s say you’re in an airplane that you want to operate under IFR flight. You have a backup altimeter in your panel that is untested. Is it (a) legal to label the backup altimeter INOP and then go fly under IFR, but (b) illegal to label the backup altimeter VFR ONLY and then go fly under IFR?

If so, that probably wouldn’t be the weirdest result of applying the FARs, but it would still be fairly weird. 🤣
Here is the Regulation 91.411 that Walt quoted so that you can read it for yourself.

Like everything in the english language, it is open for debate but be prepared to pay a lot of legal fees in a court of law. I interpret it the same way Walt does and believe most FAA inspectors will also. When that happens and one gets written up, typically it becomes what the expert witnesses have to say in court. Be prepared to pay a lot in legal fees to try and get the court to agree with your opinion.
 
Here is the Regulation 91.411 that Walt quoted so that you can read it for yourself.

Like everything in the english language, it is open for debate but be prepared to pay a lot of legal fees in a court of law. I interpret it the same way Walt does and believe most FAA inspectors will also. When that happens and one gets written up, typically it becomes what the expert witnesses have to say in court. Be prepared to pay a lot in legal fees to try and get the court to agree with your opinion.
Where I’ve ended up: I don’t think the reg is unclear (it’s actually not bad by FAA standards), I think it’s unclear whether/how placarding something might affect application of the reg.
 
I don’t think the reg decides the question, since it applies only to IFR operations. Another way to put my question is:

Let’s say you’re in an airplane that you want to operate under IFR flight. You have a backup altimeter in your panel that is untested. Is it (a) legal to label the backup altimeter INOP and then go fly under IFR, but (b) illegal to label the backup altimeter VFR ONLY and then go fly under IFR?

If so, that probably wouldn’t be the weirdest result of applying the FARs, but it would still be fairly weird. 🤣
I don't know about what the implications would be for IFR flight (I'm so out of currency it's laughable), but I'd think if you labelled it as INOP, that means ***INOP*** for ANY kind of flight. An inoperative instrument, which is supposed to be placarded as such, couldn't even be used for Day VFR. That's what "inoperative" means...doesn't operate, so don't use it AT ALL.
 
Where I’ve ended up: I don’t think the reg is unclear (it’s actually not bad by FAA standards), I think it’s unclear whether/how placarding something might affect application of the reg.
91.411 has nothing to do with inoperative instruments. If there are 2 altimeters in front of the pilot, they must work and pass the inspection when accomplishing the inspection, what happens after it leaves has nothing to do with the cert.

Maybe you could find someone who would pretend it's not there, but that's not me.
I value my customers safety and do things to keep us both safe and out of trouble.

The reason I no longer do portable certifications (other than it being a major hassle and transportation time is uncompensated), is the portable guy has a huge incentive to give you a sticker when he's done so he gets paid.

I'm a bit of a perfectionist, I want everything to be within limits (not borderline) which often means adjusting things like altimeters, encoders, transponder frequency, etc., and static leaks that will get repaired if needed.

Trust me, I know this business, and I know almost no mobile shop that can remove, bench test and calibrate these things in the field.
I'd also bet 9 out of 10 mobile shops don't have the precision test equipment that can legally calibrate an ADC or adj a xpdr.
Similar to a one-day owner assisted annual inspection you get what you pay for, if you know what I mean.
 
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I don't know about what the implications would be for IFR flight (I'm so out of currency it's laughable), but I'd think if you labelled it as INOP, that means ***INOP*** for ANY kind of flight. An inoperative instrument, which is supposed to be placarded as such, couldn't even be used for Day VFR. That's what "inoperative" means...doesn't operate, so don't use it AT ALL.
Agreed.

But the question isn’t what INOP means. It’s whether you could leave a backup altimeter untested, label it INOP (or VFR ONLY), and still fly the aircraft under IFR (using the primary, tested altimeter) without violating .411.

So you wouldn’t be using the untested backup altimeter at all.

I can see arguments either way, but no clear answer.
 
91.411 has nothing to do with inoperative instruments.
Agree completely that it doesn't talk about or address inoperative instruments. The question is whether you can declare something INOP or VFR ONLY in order to comply with .411.
If there are 2 altimeters in front of the pilot, they must work and pass the inspection.
Agree -- but only once we decide you can't legally declare one of them INOP or VFR ONLY. I don't see where the reg answers that question.

I'm going to take a dive into the separate question of "whether and when you can declare something inop" and see if there's an answer. You may well be right that you can't placard your way out of inspecting every altimeter in the aircraft. In fact, I think that would be the most sensible result. But that makes me wonder whether that's actually the result under the FARs. 🤣
 
My airplane is due for it's 14 CFR 91.411 and 91.413 checks and I just got a quote of $550 for both. This has always been a relatively simple endeavor on my airplane (One ADHARS, One Transponder) so I was a little surprised at the 267% increase in cost over the last 2 years.

Anyone else have a PIREP they'd care to share?
On June 11, 2024 I paid $200 at Fairfield County Airport in South Carolina KFDW
 
  • FAR 91.411(a)(1): "No person may operate an airplane, or helicopter, in controlled airspace under IFR unless... (1) Within the preceding 24 calendar months, each static pressure system, each altimeter instrument, and each automatic pressure altitude reporting system has been tested and inspected and found to comply with appendix E of part 43 of this chapter."

The FAR sounds pretty clear to me. Can't fly IFR unless "each static pressure system, each altimeter and each automatic pressure altitude reporting system has been tested." it says EACH in front of every type of altitude system. This means that an auto pilot that is using pressure altitude to fly IFR has to get its data from a certified system. The transponder that is reporting ADSB/MODEC data to ATC has to be sending approved altitude data from a tested system. If a G5 or GSU25 is sending air data somewhere and the device is going to be used for IFR then it needs to be tested. Theoretically one could argue with the FAA and say they were not using a specific altimeter in question, but that will certainly be a loosing argument.

Look up the case the FAA vs David Riggs. David did a low pass over a friends yard with the intent to land there. He didn't like what he saw and decided to go somewhere else. David followed the off airport landing Advisory Circular to the letter, yet he lost his case through countless appeals. The AOPA and many orgs backed his fight financially and he still lost. The FAA rules are subject to interpretation by the FAA. The only expert witnesses are called in by the FAA and they are usually FAA employees. It isn't a normal court proceeding where you can call in an expert. Only the FAA can call in an expert to testify. There is no question that if someone trying to split the hair of getting an Alt certified and gets ramped checked after an IFR flight they would be violated if the investigator discovers a non-compliant Alt. Get distracted and bust an altitude, ATC is required to report the incident. The first thing the FAA would do is request your logbook to verify you are current for IFR operations. The second thing they would do is inspect the logbooks of the Aircraft that was being flown. When they discover that some systems were not tested they will certainly suspend the license immediately. With a paid up AOPA legal plan, a good lawyer, lots of time to spend in hearings in Washington DC, flight checks with the FAA, etc. one may be able to get their license back, but they would still loose the case.
 
Then why would you own an RV? May as well go have fun in a CUB ;)

LOL.. that's a funny comment.

I built my RV-4 in the 90's and have been flying it for almost 25 years now. Over 1300 hours logged. The longer I fly it, the more I understand and appreciate the original design intent.. light weight, simple, maneuverable, fun flying, incredible visibility, simple aerobatics. Have Van himself explain it. People try to force these simple little airplanes into roles they were never intended for.
 
If a G5 or GSU25 is sending air data somewhere and the device is going to be used for IFR then it needs to be tested.
“Used for IFR” isn’t actually in the reg. (Neither is “in the pilot’s field of view.”)

As I read the reg, it requires testing of “each static pressure system, each altimeter instrument, and each automatic pressure altitude reporting system” that happens to simply be IN an aircraft that is operated under IFR, full stop.

The question, not yet resolved, is whether you can avoid the need to test backup systems that happen to be in an aircraft operated under IFR by labeling them INOP or perhaps VFR ONLY.

I can see arguments both ways.

The GPS altimeter provided by my iPad isn’t tested. Is that an untested “altimeter instrument” that is therefore illegal if I operate the aircraft under IFR? Maybe so! Perhaps there’s a definition of “altimeter instrument” that avoids that conundrum. 🤣
 
20 years flying my 6A and the transponder has not been off of 1200. Now with ADS-B requirement, I am thinking of removing the transponder till I sell the airplane.

With today's panels, no one is looking out the window..... and it's been that way for a while. I never expect them to. If you ride motorcycles, you know what I mean.

I fly local in a low traffic area and my RV reflects my mission........ It all depends on your needs.

I do have ADS-B in.
 
Look up the case the FAA vs David Riggs. David did a low pass over a friends yard with the intent to land there. He didn't like what he saw and decided to go somewhere else. David followed the off airport landing Advisory Circular to the letter, yet he lost his case through countless appeals. The AOPA and many orgs backed his fight financially and he still lost.

Ummmm....not to derail this, but a quick search on this guy...you might not want to use him as your reference case. Just sayin'.
The FAA rules are subject to interpretation by the FAA. The only expert witnesses are called in by the FAA and they are usually FAA employees. It isn't a normal court proceeding where you can call in an expert. Only the FAA can call in an expert to testify.
AFAIK, this is NOT true. But IANAL, let alone an aviation lawyer.

In the end, this whole thread is, IMO, silly. Every couple of years, just spend a relatively small amount of money, get all of your systems checked and move on. Jeez.
 
Confirmed current pricing with my guy yesterday, $500 flat fee plus $50 for each additional instrument.

"I didn't get into the avionics business to undercut the market." He did lend me an oil filter wrench, no charge. :)
 
Look up the case the FAA vs David Riggs. David did a low pass over a friends yard with the intent to land there. He didn't like what he saw and decided to go somewhere else. David followed the off airport landing Advisory Circular to the letter, yet he lost his case through countless appeals. The AOPA and many orgs backed his fight financially and he still lost. The FAA rules are subject to interpretation by the FAA. The only expert witnesses are called in by the FAA and they are usually FAA employees. It isn't a normal court proceeding where you can call in an expert. Only the FAA can call in an expert to testify. There is no question that if someone trying to split the hair of getting an Alt certified and gets ramped checked after an IFR flight they would be violated if the investigator discovers a non-compliant Alt. Get distracted and bust an altitude, ATC is required to report the incident. The first thing the FAA would do is request your logbook to verify you are current for IFR operations. The second thing they would do is inspect the logbooks of the Aircraft that was being flown. When they discover that some systems were not tested they will certainly suspend the license immediately. With a paid up AOPA legal plan, a good lawyer, lots of time to spend in hearings in Washington DC, flight checks with the FAA, etc. one may be able to get their license back, but they would still loose the case.
I thought David Riggs got pinched for buzzing the Santa Monica pier in an L-39. The story above sounds more like Trent Palmer's recent FAA troubles. That issue is still ongoing and he's still flying AFAIK, but he does appear to be getting egregiously hosed by the FAA
 
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20 years flying my 6A and the transponder has not been off of 1200. Now with ADS-B requirement, I am thinking of removing the transponder till I sell the airplane.

With today's panels, no one is looking out the window..... and it's been that way for a while. I never expect them to. If you ride motorcycles, you know what I mean.

I fly local in a low traffic area and my RV reflects my mission........ It all depends on your needs.

I do have ADS-B in.
I don’t understand this statement. Having or not having a transponder does not change the ADSB-out rules.
BTW, if you have only adsb-in, you won’t get all the traffic that someone who also has adsb-out gets.
 
“Used for IFR” isn’t actually in the reg. (Neither is “in the pilot’s field of view.”)

As I read the reg, it requires testing of “each static pressure system, each altimeter instrument, and each automatic pressure altitude reporting system” that happens to simply be IN an aircraft that is operated under IFR, full stop.

The question, not yet resolved, is whether you can avoid the need to test backup systems that happen to be in an aircraft operated under IFR by labeling them INOP or perhaps VFR ONLY.

I can see arguments both ways.

The GPS altimeter provided by my iPad isn’t tested. Is that an untested “altimeter instrument” that is therefore illegal if I operate the aircraft under IFR? Maybe so! Perhaps there’s a definition of “altimeter instrument” that avoids that conundrum. 🤣
Well, since the gps provides true altitude, not barometric altitude, it’s probably not any kind of altimeter by faa definition!
 
Well, since the gps provides true altitude, not barometric altitude, it’s probably not any kind of altimeter by faa definition!
Who knows?!? I wonder if you could get in trouble for carrying an untested barometric altimeter in your pocket while flying under IFR. 🤣
 
I don’t understand this statement. Having or not having a transponder does not change the ADSB-out rules.
BTW, if you have only adsb-in, you won’t get all the traffic that someone who also has adsb-out gets.
It does not change them, Right. It matches them.
If I need ADS-B out to go where the transponder allowed me to go, and I never go there and decide to not install ADS-B, then I see no value in maintaining a transponder.

Flying with your landing lights on FULL TIME will allow your aircraft to be very visible.. but no one does it.
 
Since we are talking about alt calibration, can the G5 be adjusted, mine is within the 20’ requirement, but just barely.
 
Flying with your landing lights on FULL TIME will allow your aircraft to be very visible.. but no one does it.

I guess I'm no one, then. Come to think of it, I know quite a few no ones.

--Ron (veteran of a mid air collision 20 years ago)
 
Walt is right on here. We run a Repair Station at work, and the amount of hoops we have to jump through to keep the feds happy is borderline ridiculous.

What you really need to complaining about is why this needs to be done by a Repair Station in the first place. As an A&P/IA I can perform and/or sign off annuals, overhauls, major structural repairs, mods, etc.... including some really critical, invasive stuff. But once every 2 years I have to bring my plane to a Repair Station where they take the newest kid in the shop, who may not even be an A&P, and have him perform what is essentially basic, routine inspections and maintenance.
The FAA really ought to consider letting A&P's, or at least IA's, do these checks. I'm fine with requiring equipment cals (my torque wrench requires one also), and special training.
I think “borderline” is the wrong word…
 
Since we are talking about alt calibration, can the G5 be adjusted, mine is within the 20’ requirement, but just barely.
When I installed the Straus ESG to have ADS-B out, I had to pay for BOTH G5s to be calibrated since the primary G5 was used to provide serial altitude data to the transponder. Only one was connected to the transponder but the other one would be a backup if the primary one stopped working or at least that is what I was told.
 
When I installed the Straus ESG to have ADS-B out, I had to pay for BOTH G5s to be calibrated since the primary G5 was used to provide serial altitude data to the transponder. Only one was connected to the transponder but the other one would be a backup if the primary one stopped working or at least that is what I was told.
Good for them, I also verify, and calibrate if req'd, a G5 being used as an HSI as it is also a standby altimeter.
It will not provide alt data to xpdr if the primary G5 fails, but I still consider it an installed altimeter.
 
When I installed the Straus ESG to have ADS-B out, I had to pay for BOTH G5s to be calibrated since the primary G5 was used to provide serial altitude data to the transponder. Only one was connected to the transponder but the other one would be a backup if the primary one stopped working or at least that is what I was told.
I like using a G5 as a primary digital altitude source for non GSU panels. G5 as an encoder is as good as it comes. The G5 air data system effectively makes it a digital encoding altimeter. That's part of why it's a complete backup ADHRS for a failed GSU LRU. Since an encoding altimeter replaces a "blind" encoder the altitude it shows at 29.92 is what you get for Mode C and ADS-B out or any other device using it as an altitude source. The encoding altimeter configuration also makes it less likely to need a bench testing for correspondence since the altitude source is integrated. The traditional altimeter correspondence test is done to ensure altitude data from an aircraft's altitude encoder and its altimeter match. So with a primary G5 used as an altitude source the altitude always corresponds 100% since both items are the same device. The G5 always "corresponds" to itself. A repair station's pitot/static test set can be run up and down in altitude and the G5 will always match its own data. Any other altimeters like a second G5 or steam gauge altimeter would have to be checked for correspondence with the altitude shown on primary G5. As an added bonus to the encoding altimeter is that there is no extra static plumbing or wiring required with a blind encoder. Less points of failure like static leaks or harness problems. Notwithstanding all this the altitude on the altimeter will also be checked against the calibrated test set's altitude values so the test set still has to be hooked into the aircraft's static system. And if a technician can do a correspondence check with an analog altimeter involved in less than an hour he hasn't taken into account the proper time to allow for hysteresis lag.
 
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The question, not yet resolved, is whether you can avoid the need to test backup systems that happen to be in an aircraft operated under IFR by labeling them INOP or perhaps VFR ONLY.
First part of the answer:

I could be wrong (it's something of a legal thicket), so nobody should rely on this, but I don't think labeling it "INOP" would get you out of the inspection requirement.

First, it is true that a pilot flying under Part 91, in an aircraft without a minimum equipment list, can declare certain instruments to be inoperative, assuming they aren't regulatorily required for flight (basically). See FAR 91.213(d). However, the offending instrument then has to be (a) removed and its control placarded (with a corresponding maintenance entry, which I'm not sure is actually required in an EAB...), or (b) "Deactivated and placarded 'Inoperative,'" again with a maintenance entry if applicable. There appears to be no definition of "deactivated," but it's hard to imagine that a "deactivated" altimeter could still be used as a backup instrument to show altitude.

And it gets worse: assuming something is properly declared INOP, you can't just fly around with it like that forever. Instead, the gadget has to be " "repaired, replaced, removed, or inspected at the next required inspection," according to FAR 91.405(c) and the De Joseph letter.

Next question: can you evade the inspection requirement by labeling a backup altimeter "VFR ONLY"? The suspense is killing me! 🤣
 
Next question: can you evade the inspection requirement by labeling a backup altimeter "VFR ONLY"? The suspense is killing me! 🤣
Well, I don’t know the answer. But I do know that there are a large number of aircraft flying with GPS devices that are not faa-legal for use as primary navigation under IFR. E.g., many if not most efis boxes have a non-TSO’d gps inside. Are they marked ‘vfr only’ ? (I don’t think so).
 
Well, I don’t know the answer. But I do know that there are a large number of aircraft flying with GPS devices that are not faa-legal for use as primary navigation under IFR. E.g., many if not most efis boxes have a non-TSO’d gps inside. Are they marked ‘vfr only’ ? (I don’t think so).
Almost certainly not. But it wouldn’t matter!
 
The GPS altimeter provided by my iPad isn’t tested. Is that an untested “altimeter instrument” that is therefore illegal if I operate the aircraft under IFR? Maybe so! Perhaps there’s a definition of “altimeter instrument” that avoids that conundrum. 🤣
Your iPad is not legal to use in flight for primary navigation. It is an Electronic Flight Bag intended to easily contain charts and data. It is not a primary instrument or connected to the aircraft pitot/static system. It only gets GPS altitude that is far from being accurate enough to fly by. To use a GPS for IFR, it must either be TSO'ed or be tested to conform to TSO standards. This is why the GPS in the G3X cannot be used for IFR navigation or even feed the transponder for ADSB data. The G3X has a WAAS GPS, but it does not conform to TSO testing standards.

Well, I don’t know the answer. But I do know that there are a large number of aircraft flying with GPS devices that are not faa-legal for use as primary navigation under IFR. E.g., many if not most efis boxes have a non-TSO’d gps inside. Are they marked ‘vfr only’ ? (I don’t think so).
GPS units are actually marked as VFR only. The first bullet for the G3X GUD says:
  • Advanced flight displays with built-in VFR WAAS GPS
TSO'ed units have TSO labels that clearly stay what sections they comply with. If those markings are not there it cannot be used for IFR navigation. It is the pilots responsibility to know even if they don't own the airplane. A non-TSO'ed GPS can be used for situational awareness, but not for approaches. The problem with Altimeters is they become a source of truth of the actual altitude. That is why they need to be certified every 24 months. 100 ft out of calibration plus being 50 or so feet off could end up hitting tress and towers on an approach.
 
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Who knows?!? I wonder if you could get in trouble for carrying an untested barometric altimeter in your pocket while flying under IFR. 🤣
According the Pilot's Handbook of Aeronautical Knowledge, "The altimeter is an instrument that measures the height of an aircraft above a given pressure level."
Well, I don’t know the answer. But I do know that there are a large number of aircraft flying with GPS devices that are not faa-legal for use as primary navigation under IFR. E.g., many if not most efis boxes have a non-TSO’d gps inside. Are they marked ‘vfr only’ ? (I don’t think so).
You can have all the non-TSO'd GPS devices you want, but if you're using them as your primary (or sole) navigation source for IFR flight, it's illegal. If you're using GPS for IFR, it MUST be TSO'd. (Note that the EFIS display with PFD data and the like need not be...which is why whole bunches of us use a certified navigator like a 430W, etc., feeding an EFIS like a Dynon).
 
  • FAR 91.411(a)(1): "No person may operate an airplane, or helicopter, in controlled airspace under IFR unless... (1) Within the preceding 24 calendar months, each static pressure system, each altimeter instrument, and each automatic pressure altitude reporting system has been tested and inspected and found to comply with appendix E of part 43 of this chapter."

The FAR sounds pretty clear to me. Can't fly IFR unless "each static pressure system, each altimeter and each automatic pressure altitude reporting system has been tested." it says EACH in front of every type of altitude system. This means that an auto pilot that is using pressure altitude to fly IFR has to get its data from a certified system. The transponder that is reporting ADSB/MODEC data to ATC has to be sending approved altitude data from a tested system. If a G5 or GSU25 is sending air data somewhere and the device is going to be used for IFR then it needs to be tested. Theoretically one could argue with the FAA and say they were not using a specific altimeter in question, but that will certainly be a loosing argument.

Look up the case the FAA vs David Riggs. David did a low pass over a friends yard with the intent to land there. He didn't like what he saw and decided to go somewhere else. David followed the off airport landing Advisory Circular to the letter, yet he lost his case through countless appeals. The AOPA and many orgs backed his fight financially and he still lost. The FAA rules are subject to interpretation by the FAA. The only expert witnesses are called in by the FAA and they are usually FAA employees. It isn't a normal court proceeding where you can call in an expert. Only the FAA can call in an expert to testify. There is no question that if someone trying to split the hair of getting an Alt certified and gets ramped checked after an IFR flight they would be violated if the investigator discovers a non-compliant Alt. Get distracted and bust an altitude, ATC is required to report the incident. The first thing the FAA would do is request your logbook to verify you are current for IFR operations. The second thing they would do is inspect the logbooks of the Aircraft that was being flown. When they discover that some systems were not tested they will certainly suspend the license immediately. With a paid up AOPA legal plan, a good lawyer, lots of time to spend in hearings in Washington DC, flight checks with the FAA, etc. one may be able to get their license back, but they would still loose the case.
This sounds more like Trent Palmer and his case is now closed. He lost. The good thing is that the current administration just signed into law an update to the Regulations where this should not happen again.

"The [FAA] Administrator shall not apply [FAR 91.119] … in any manner that requires a pilot to continue a landing that is unsafe.”

AOPA just posted an article on it.
 
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Perhaps those that complain about the high prices should see what it takes to open their own FAA repair station, purchase all the test equipment maintain a facility that has fixed overhead costs, ground equipment, insurance, etc etc.... (not to mention dealing with the FAA paperwork requirements and audits.)

I actually hear this alot, "that's pretty good money for 30min work", however they usually say WOW when I tell them the test box I just used (AVX-10) to test their transponder/ADS-B cost 18K. The P-S test box I use (Laversab 6300) is a highly accurate RVSM certified unit so I can calibrate your air data unit, it costs about 17K without accessories. Annual certification costs for these boxes: $1600.

And I think my time (or any other employed technician) and experience is worth something?

So, If someone thinks I'm "gouging" them ($195 for xpdr and $450-495 avg for 91.411/91.413) then I encourage them to go somewhere else.

And for my soapbox, please don't show up to a shop, let someone work on your stuff for hours and then say I didn't bring any money...

And yes, glass panels require higher accuracy test equipment (compared analog altimeters) which costs more to purchase and certify.
Well said Walt. I did certs for SteinAir when I was there and second everything you've mentioned.
 
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