Transponder Check

[JohnWF]

I asked an avionics shop if they would give me a VFR transponder check. They replied that if I used/had Mode C they would HAVE to do an IFR transponder check and a pitot leak check. My LSA cannot be used for IFR (not properly equipped) nor is it allowed to fly above 10,000

I won't be going to this shop because their statement that I had to have IFR certification doesn't seem right. Your take?

 

[Greg Bockelman]

Well, for what it is worth, I never had to do an IFR check just because I had a mode C.

 

[Geico266]

Call ATC and see if it is reporting accurately.

 

[poadeleted20]

In reviewing 14 CFR 91.413 and Appendix F to Part 43, I cannot find anything saying there's any sort of different transponder test for a transponder being used for VFR only versus one also used for IFR flying. Can someone point out what I'm missing?

 

[Geico266]

In reviewing 14 CFR 91.413 and Appendix F to Part 43, I cannot find anything saying there's any sort of different transponder test for a transponder being used for VFR only versus one also used for IFR flying. Can someone point out what I'm missing?

Because you verify the altitude when you check in?

I've had to pay for certification a couple of times on IFR aircraft, but I'm VFR only.

 

[poadeleted21]

In reviewing 14 CFR 91.413 and Appendix F to Part 43, I cannot find anything saying there's any sort of different transponder test for a transponder being used for VFR only versus one also used for IFR flying. Can someone point out what I'm missing?

Is a static check required for a transponder check? I typically get the transponder and the IFR sign off done at the same time.

 

[BillTIZ]

I get transponder checks, 91.413, not pitot static altimeter checks, 91.411.
I have a blind encoder for the altitude portion of the Mode C. Nothing the shop can do during a pitot static check will impact the ModeC readout.

I only pay for 91.413 checks.

 

[BillTIZ]

In reviewing 14 CFR 91.413 and Appendix F to Part 43, I cannot find anything saying there's any sort of different transponder test for a transponder being used for VFR only versus one also used for IFR flying. Can someone point out what I'm missing?

Many misquote a transponder only check as a VFR check (91.413) and refer to the pitot static check as an IFR check (91.411).

The OP needs to specify he wants a 91.413 check.
It might help if he tells the shop his aircraft is not certified for IFR operations and a 91.411 pitot static check is not required.

 

[poadeleted20]

Is a static check required for a transponder check?

If you are asking whether the 91.411 altimeter/static system check required for IFR operation is also required when you do the 91.413 transponder check required for transponder use, no, it is not.

I typically get the transponder and the IFR sign off done at the same time.

Most people do that, since much of the work required for one is required for the other. The shop I use charges $200 for either alone and $250 for both together.

 

[lr60plt]

Yup - they should only have to do the "vfr" transponder check. Had mine done for 100 bucks last time. Check with a couple other shops.

 

[poadeleted20]

Many misquote a transponder only check as a VFR check (91.413) and refer to the pitot static check as an IFR check (91.411).

The underlined is a common misnomer. The 91.411 check required for IFR operation is an altimeter/static system check. In addition to testing the static system for leaks, the altimeter is tested for accuracy as part of the 91.411 check, but the pitot system is not checked at all.

 

[BillTIZ]

The underlined is a common misnomer. The 91.411 check required for IFR operation is an altimeter/static system check. In addition to testing the static system for leaks, the altimeter is tested for accuracy as part of the 91.411 check, but the pitot system is not checked at all.

Agreed! My comment was "what most refer to". That does not always mean the ask for the right thing. What they really need.

 

[gismo]

The underlined is a common misnomer. The 91.411 check required for IFR operation is an altimeter/static system check. In addition to testing the static system for leaks, the altimeter is tested for accuracy as part of the 91.411 check, but the pitot system is not checked at all.

I think part of the confusion is that in order to perform a static/altimeter check the tester gets connected to the pitot and static systems. The pitot connection is needed to protect the ASI from adverse differential pressures. Plus the test sets typically include a "calibrated" ASI that can be used to check the accuracy of the onboard ASI (of course this check completely ignores the most common cause of ASI errors).

 

[bgdriveway]

For the OP, we have a guy come in and do transponder only checks all the time. On R22/44's you are wasting money most of the time to do both. They aren't going IFR. If the shop won't do just a transponder check, find another one.

On the following question.....if I wanted to, I could pull an altimeter, send it to a shop for a calibration, reinstall it, do a leak check on the static system only and fly IFR?

Maybe it's just the common misunderstanding, but I thought that they were supposed to (required) leak check the Pitot system as well. Is that just because the shops want to cover themselves?

Granted it's more work to do all that than just pay the guy to do the thing in place.

 

[N801BH]

I get transponder checks, 91.413, not pitot static altimeter checks, 91.411.
I have a blind encoder for the altitude portion of the Mode C. Nothing the shop can do during a pitot static check will impact the ModeC readout.

I only pay for 91.413 checks.

Hmmm..

I installed my transponder and blind encoder in my experimental... The blind encoder IS hooked into the static system.. That is how it gets its baro information... To test the transponder, the technician hooks up to the static port and feeds it a caliberated pressure /vacuum....

 

[poadeleted20]

On the following question.....if I wanted to, I could pull an altimeter, send it to a shop for a calibration, reinstall it, do a leak check on the static system only and fly IFR?

No. The 91.411 certification requires an "integrated system test", not just a leak check after altimeter installation.

Maybe it's just the common misunderstanding, but I thought that they were supposed to (required) leak check the Pitot system as well.

There is no such requirement in either 91.411 or 91.413 or the applicable Appendices to Part 43 (Appendices E and F).

Is that just because the shops want to cover themselves?

I've never heard of a shop doing a check of the pitot system during a 91.411 or 91.413 inspection -- at least, not without specific customer request and an extra charge for the extra work.

 

[EdFred]

I've never heard of a shop doing a check of the pitot system during a 91.411 or 91.413 inspection -- at least, not without specific customer request and an extra charge for the extra work.

Last one I had done, they did. No extra charge. But then again, I have more than a one way relationship with the shop.