Avionics VFR/IFR

6612v

Filing Flight Plan
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TJ CFIAI
Seems to be a lot of confusion on VFR and IFR requirements. I tell my students, READ THE REGS. If your going to fly an aircraft VFR under part 91 then you must meet the minimum VFR equipment list for part 91. If your going to fly IFR under part 91 then you must have the minimum IFR equipment list, and those instruments/avionics must be properly/ currently certified for IFR. If you add a non TSO piece of avionics, and fly under part 91, not for hire, then it can not replace or effect or interfere with any of the required avionics or systems necessary for the intended flight whether VFR or IFR. Non TSO equipment may be permissible to install and use over and beyond the minimum VFR equipment list, but must be signed off by an appropriate A/P to concur the installation will not interfere or compromise any of the aircraft required systems. These are only the basic guidelines, there may be exceptions to your particular application. If there be some that disagree with my understanding, I invite them to correct me using the appropriate regulations.
 
You're explanation is incomplete. TSO is neither necessary nor sufficient for most equipment in an aircraft. The only time it makes a difference for IFR flight avionics is IFR GPS and other RNAV. A TSO only guarantees compliance with the TSO requirements. While for GPSs the getting the TSO will certainly have checks to see that it is not being interfered with by the COMM radio, for example, it doesn't give any blanket assurance that if you have an entire TSO stack of avionics that you're free of cross-interference issues.

In other appliances, TSO is required (ELTs and transponders). For others, it's not required for part 91 small ops. Just because an item has a TSO doesn't mean you can stick it in your aircraft, either. It is, however, one of the ways (but not the only way), that a device might meet that requirement. It is also one of the ways (but again, not the only way) that a device can be legally manufactured as an aircraft part.
 
Non TSO equipment may be permissible to install
FYI: a TSO is not an installation approval, only a design/production approval. The equipment install falls under Part 43. As to "non-TSO" equipment, most FARs only stipulate the equipment meets (key word) the TSO spec not that it must be produced under the TSO spec. Where ever there is a specific requirement for equipment to be produced under TSO, the regulation or other rule will state that.
 
For most things, you don't even need to "meet" the TSO.
 
I believe that the transponder must also be TSO'd.

Close, but not exactly.

91.215 is worded as follows:

ATC transponder equipment installed must meet the performance and environmental requirements of any class of TSO-C74b (Mode A) or any class of TSO-C74c (Mode A with altitude reporting capability) as appropriate, or the appropriate class of TSO-C112 (Mode S).

So the weasel words "must meet the performance and environmental requirements of ..." allows for a non TSO transponder that meets the performance and environmental requirements specified in the TSO.
 
As I said, this information was only basic information, not all inclusive. There are many aircraft with avionics that are without TSO, STC, or PMA equipment in them but were approved for that aircraft. I was only implying that many folks listen to hanger talk and should do a little regulation research for themselves. I have received my share of bogus information from different posts and even a couple of so called A/Ps over the years because they were trying to get in my pocket. Part 91 leaves a lot of latitude for equipment that can be used. Equipment such as Transponders, Altitude encoders, ADSB out and ELTs are examples of TSO required under part 91. Equipment over and beyond the minimum Part 91 required equipment list only have to be manufacturer approved, but again that is no guarantee against cross-interference issues. As for IFR flight, the rules are more stringent. Any avionics that fall within the minimum required lists for IFR flight must meet TSO. This includes any optional equipment that is necessary to perform any portion of the IFR tasks for the flight you have filed for. Example: GPS is not on the minimum required lists for IFR, but if you file a flight plan that requires the use of a GPS, that GPS is now included in the IFR minimum equipment list and must be TSO. Again this is certainly not all inclusive, but I like the buzz it creates. I will say this, the FAA regulations must be read slowly, pay attention what is included, pay more attention to what is not.
 
As I said, this information was only basic information, not all inclusive. There are many aircraft with avionics that are without TSO, STC, or PMA equipment in them but were approved for that aircraft. I was only implying that many folks listen to hanger talk and should do a little regulation research for themselves. I have received my share of bogus information from different posts and even a couple of so called A/Ps over the years because they were trying to get in my pocket. Part 91 leaves a lot of latitude for equipment that can be used. Equipment such as Transponders, Altitude encoders, ADSB out and ELTs are examples of TSO required under part 91. Equipment over and beyond the minimum Part 91 required equipment list only have to be manufacturer approved, but again that is no guarantee against cross-interference issues. As for IFR flight, the rules are more stringent. Any avionics that fall within the minimum required lists for IFR flight must meet TSO. This includes any optional equipment that is necessary to perform any portion of the IFR tasks for the flight you have filed for. Example: GPS is not on the minimum required lists for IFR, but if you file a flight plan that requires the use of a GPS, that GPS is now included in the IFR minimum equipment list and must be TSO. Again this is certainly not all inclusive, but I like the buzz it creates. I will say this, the FAA regulations must be read slowly, pay attention what is included, pay more attention to what is not.
Pull up 91.205 and point to me where TSO is mentioned.... TSO has to do with design/manufacture, not with use.

(d) Instrument flight rules. For IFR flight, the following instruments and equipment are required:

(1) Instruments and equipment specified in paragraph (b) of this section, and, for night flight, instruments and equipment specified in paragraph (c) of this section.

(2) Two-way radio communication and navigation equipment suitable for the route to be flown.

(3) Gyroscopic rate-of-turn indicator, except on the following aircraft:

(i) Airplanes with a third attitude instrument system usable through flight attitudes of 360 degrees of pitch and roll and installed in accordance with the instrument requirements prescribed in § 121.305(j) of this chapter; and

(ii) Rotorcraft with a third attitude instrument system usable through flight attitudes of ±80 degrees of pitch and ±120 degrees of roll and installed in accordance with § 29.1303(g) of this chapter.

(4) Slip-skid indicator.

(5) Sensitive altimeter adjustable for barometric pressure.

(6) A clock displaying hours, minutes, and seconds with a sweep-second pointer or digital presentation.

(7) Generator or alternator of adequate capacity.

(8) Gyroscopic pitch and bank indicator (artificial horizon).

(9) Gyroscopic direction indicator (directional gyro or equivalent).
 
are examples of TSO required under part 91
for IFR flight must meet TSO
that GPS is now included in the IFR minimum equipment list and must be TSO
the FAA regulations must be read slowly, pay attention what is included, pay more attention to what is not
Why the separate thread? FWIW: I don't know where you're getting your information from, but the 1st three quotes above are not correct. If you are implying that if an piece of equipment "meets the performance of a TSO" equates to having a TSO approval then that is not correct either. Perhaps in light of the 4th quote above, you might want to read up on TSOAs in Part 21 and their associated ACs and Orders.;)
 
Close, but not exactly.

91.215 is worded as follows:



So the weasel words "must meet the performance and environmental requirements of ..." allows for a non TSO transponder that meets the performance and environmental requirements specified in the TSO.
That's what I meant. But also to the point, how many people have the knowledge and resources to verify that a non-TSO'd transponder or ELT meet the TSO requirements?
 
how many people have the knowledge and resources to verify that a non-TSO'd transponder or ELT meet the TSO requirements?
The person installing the equipment needs to be able to make that determination through various references. Some equipment OEMs state they meet TSO performance on their spec sheets but most leave it to the installer to compare their spec sheets to the TSO requirements.
 
That's what I meant. But also to the point, how many people have the knowledge and resources to verify that a non-TSO'd transponder or ELT meet the TSO requirements?
please show me a NON TSO'ed transponder. Ive never seen one. as it has been pointed out, the only thing that needs to be TSO'ed for IFR is what is required by regs to be TSO'ed. IE transponders,elt's, and IFR GPS units and afew more exoctic boxes.
 
please show me a NON TSO'ed transponder.
Look at any xspndr sold for "experimental" only and it will not have a TSO number on its tag. Appareo has a couple models as do other OEMs.
 
please show me a NON TSO'ed transponder. Ive never seen one. as it has been pointed out, the only thing that needs to be TSO'ed for IFR is what is required by regs to be TSO'ed. IE transponders,elt's, and IFR GPS units and afew more exoctic boxes.
Do I really need to point out where you're wrong? Because I'm pretty sure you could figure it out on your own.
 
As I said, this information was only basic information, not all inclusive. There are many aircraft with avionics that are without TSO, STC, or PMA equipment in them but were approved for that aircraft. I was only implying that many folks listen to hanger talk and should do a little regulation research for themselves. I have received my share of bogus information from different posts and even a couple of so called A/Ps over the years because they were trying to get in my pocket. Part 91 leaves a lot of latitude for equipment that can be used. Equipment such as Transponders, Altitude encoders, ADSB out and ELTs are examples of TSO required under part 91. Equipment over and beyond the minimum Part 91 required equipment list only have to be manufacturer approved, but again that is no guarantee against cross-interference issues. As for IFR flight, the rules are more stringent. Any avionics that fall within the minimum required lists for IFR flight must meet TSO. This includes any optional equipment that is necessary to perform any portion of the IFR tasks for the flight you have filed for. Example: GPS is not on the minimum required lists for IFR, but if you file a flight plan that requires the use of a GPS, that GPS is now included in the IFR minimum equipment list and must be TSO. Again this is certainly not all inclusive, but I like the buzz it creates. I will say this, the FAA regulations must be read slowly, pay attention what is included, pay more attention to what is not.

This is how bad/misinformation gets spread. You're speaking authoritatively on an issue you clearly don't fully understand.
 
Look at any xspndr sold for "experimental" only and it will not have a TSO number on its tag. Appareo has a couple models as do other OEMs.
your right. i really didnt say what i meant to say. I have never seen a transponder that did not "meet" the requirements of the TSO. which is what 91.215 says. I will not get into the argument about installing an "experimental" transponder that meets the requirements of the TSO in a type certificated aircraft.
 
I will not get into the argument about installing an "experimental" transponder that meets the requirements of the TSO in a type certificated aircraft.
FWIW: Never viewed the topic as an argument, only as an alternate installation method. Even though "experimental" is not a valid appliance/equipment category, vendors use the "experimental" label not to run afoul of Part 3. For comparison, Wag-Aero has been using an in-house Product Code for years that puts the use of the equipment where it should be: the FSDO or mechanic. Vendors do not determine what gets installed in an aircraft. For another more in depth view on the topic:
https://www.valavionics.com/installation-in-type-certificated-aircraft.html
 
FWIW: Never viewed the topic as an argument, only as an alternate installation method. Even though "experimental" is not a valid appliance/equipment category, vendors use the "experimental" label not to run afoul of Part 3. For comparison, Wag-Aero has been using an in-house Product Code for years that puts the use of the equipment where it should be: the FSDO or mechanic. Vendors do not determine what gets installed in an aircraft. For another more in depth view on the topic:
https://www.valavionics.com/installation-in-type-certificarated-aircraft.html
im 100% with you on that. but there are a lot of people out there that do not agree. look how many believe that you must do a 337 to install a radio in an aircraft.
 
Look at any xspndr sold for "experimental" only and it will not have a TSO number on its tag. Appareo has a couple models as do other OEMs.
You're partially wrong there. The Appareo ES/ESG not only "meets" the TSO-C112e (transponders) and C116b (extended squitter) specs, it has FAA approval for those. Initially they were sold without it but they've had it for several years now (I'm looking at the approval letter dated in 2016). There's a third TSO, the C145d which covers the GPS in the ESG. They meet that, though I'm not sure they have TSOA on that. These are the only two TRANSPONDER models that Appareo has ever made/sold.
 
Seems like two different things are being confused.

1) There is a TSO issued by the FAA which is a performance standard. 2) There is a TSO Approval granted to a company to state that a product and the supporting business systems behind the product meet the TSO standard.

A product can perform and meet the TSO standard without having a TSO Approval. Can that product ever be installed to a certificated aircraft?
 
You're partially wrong there....... The Appareo ES/ESG not only "meets" the TSO-C112e (transponders) and C116b (extended squitter) specs, it has FAA approval for those.
How so? I believe I stated the xspndrs would be marked differently not manufactured/produced differently. That is the key to this topic. And part of the reason for the FARs to say “meet the TSO.”

So if all Appareo xspndrs are “FAA approved” as you’re stating above, why does Appareo still sell 2 versions of the ES and ESG – one version “experimental” and the other “certified??” And as a bonus question for you, how do you tell the difference between the two versions other than their P/N?
 
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There is a TSO Approval granted to a company to state that a product and the supporting business systems behind the product meet the TSO standard.
FYI: It's technically a TSO Authorization (TSOA) which authorizes the vendor/OEM to design and produce a specific article per the TSO to include how the article is required to be marked.
Can that product ever be installed to a certificated aircraft?
Yes.
 
How so? I believe I stated the xspndrs would be marked differently not manufactured/produced differently. That is the key to this topic. And part of the reason for the FARs to say “meet the TSO.”

So if all Appareo xspndrs are “FAA approved” as you’re stating above, why does Appareo still sell 2 versions of the ES and ESG – one version “experimental” and the other “certified??” And as a bonus question for you, how do you tell the difference between the two versions other than their P/N?
The reason they sell two versions is ONE has as GPS in it and the other doesn't. In either case, the MODE S (regular and ES) does have TSOA. What they don't have is TSOA on the WAAS GPS in the ESG and hence that one can not be used in certificated aircraft to meet the ADSB mandate.
 
The reason they sell two versions is ONE has as GPS in it and the other doesn't.
Not quite. I think you missed the point. So without drifting this thread too far from the TSO/non-TSO topic...

There are TWO versions of the ES and TWO versions of the ESG, each under a different P/N and aircraft type: "experimental" and "certified." All 4 versions are marketed as ADS-B compliant. In addition, the "cert" version can only be shipped to an Appareo dealer whereas the "exp" version can be sold over-the-counter. FYI: I've installed 2 of the 4.;)
ESG: P/N: 153010-000040 (exp)
ESG: P/N: 153010-000050 (cert)
ES: P/N: 153010-000040 (exp)
ES: P/N: 153010-000039 (cert)

So, back to the questions: Since you state above all Appareo xspndrs are “FAA approved", why does Appareo still sell "experimental" versions of the ES and ESG at a reduced cost? And what distinguishes the difference between the exp/cert units other than P/N?
 
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That is not at all the same as ordering an "experimental install kit" and inside the kit box you find a 153010-000050 or 153010-000039 part numbers with matching tags, which is what is happening exactly on some very popular items. One item I can think of, the only different between the experimental and the STC kit is that one comes STC LOA and not the other does not. The LRUs have the same same part numbers and same FAA/PMA tags, in this case the STC covers multiple installation of the LRU in different configurations.
 
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The LRUs have the same same part numbers and same FAA/PMA tags
Interesting. So if you order a 153010-000040 "exp", LRU only, for $100 less, they'll send you a 153010-000039 "cert" LRU?
 
Interesting. So if you order a 153010-000040 "exp", LRU only, for $100 less, they'll send you a 153010-000039 "cert" LRU?

The vendor I’m taking about yes, the experimental kit comes with the certified LRU. I should mention the certified kit comes with 8130-3 and the STC LOA. the LRUs in both kits are identical down to the FAA/PMA tags
 
the experimental kit comes with the certified LRU.
You mention "kits" but is the same true for just the standalone unit? And are the exp kits still cheaper than the cert kits? If so would you mind sharing the vendor name here or PM? Most exp avionics/articles I installed had different tags than the cert versions which usually just dropped the TSO or PMA references.
 
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