Transponder check required?

[drigotti]

Does a new install on a newly homebuilt airplane need a transponder cert? Regardless of EAB or ELSA? I'm talking VFR only.

Thank You

[Vision401]

According to 14 CFR 91.413, a transponder may not be used for the above purposes unless, within the preceding 24 calendar months, the ATC transponder has been tested and inspected and found to comply with appendix F of FAR Part 43.
for "above purposes" see
http://www.aopa.org/Pilot-Resources/PIC-archive/Equipment/Transponder-Requirements

The use of a transponder in airspace does not reflect what aircraft it is in.

[skyfixer8]

Even though not required unless you are going to be flying IFR, I would go with the added expense of an encoder also. ATC will be able to see you better and know your altitude and speed to warn other planes to be cautious of your wake turbulence. :cool:

[67jwbruce]

Any use of Class A, B, or C will require you to install and have certified a transponder (Modes A and C)... Any use of a TRSA will require at least the Mode A transponder (installed and certified).

But why not just skip ahead and meet the ADS-B requirements instead?

[Jim Hann]

Any use of Class A, B, or C will require you to install and have certified a transponder (Modes A and C)... Any use of a TRSA will require at least the Mode A transponder (installed and certified).

But why not just skip ahead and meet the ADS-B requirements instead?
I agree with the ADS-B if you can afford it. Remember it doesn't have to be certificated equipment in an E-AB The equipment just has to meet the performance standards, so it has to pass the test that is required under 14CFR91

[MPerkins]

This is the way I understand it. . . . To fly in Mode-C areas beginning in 2020, the aircraft must still be equipped with a Mode-C transponder, even if it's equipped with ADS-B out. I understand that the FAA has no immediate plans to remove the Mode-C transponder requirement, even with ADS-B out, if that ADS-B out is a UAT transmitter. However, if you were to choose a 1090ES version of ADS-B out, it can be used in place of a transponder because it operates with traditional radar and TCAS, in addition to providing the function of ADS-B out. Actually, 1090ES ADS-B is a transponder, but has "extended squitter," meaning it sends the additional data required for ADS-B. The reason is that TCAS still depends on transponders (or 1090ES ADS-B). So I don't think you can really "skip ahead" to ADS-B out and avoid installing a transponder, unless it's 1090ES. Check me on this, but this was my reference: https://www.faa.gov/nextgen/programs/adsb/faq/#21

[Bob H]

I have used ATC as a transponder check source here in Calif desert area. If we fly early on a Sunday morning when ATC has little activity and ask for a sqwauk, they usually are happy to respond and we compare altitude readings. Whole process takes less than a minute. If readings are within 100', I call it good. It's not a legal check but can indicate if something is out of spec.

[67jwbruce]

This is the way I understand it. . . . To fly in Mode-C areas beginning in 2020, the aircraft must still be equipped with a Mode-C transponder, even if it's equipped with ADS-B out. I understand that the FAA has no immediate plans to remove the Mode-C transponder requirement, even with ADS-B out, if that ADS-B out is a UAT transmitter. However, if you were to choose a 1090ES version of ADS-B out, it can be used in place of a transponder because it operates with traditional radar and TCAS, in addition to providing the function of ADS-B out. Actually, 1090ES ADS-B is a transponder, but has "extended squitter," meaning it sends the additional data required for ADS-B. The reason is that TCAS still depends on transponders (or 1090ES ADS-B). So I don't think you can really "skip ahead" to ADS-B out and avoid installing a transponder, unless it's 1090ES. Check me on this, but this was my reference: https://www.faa.gov/nextgen/programs/adsb/faq/#21

Thanks!

[Jim Hann]

This is the way I understand it. . . . To fly in Mode-C areas beginning in 2020, the aircraft must still be equipped with a Mode-C transponder, even if it's equipped with ADS-B out. I understand that the FAA has no immediate plans to remove the Mode-C transponder requirement, even with ADS-B out, if that ADS-B out is a UAT transmitter. However, if you were to choose a 1090ES version of ADS-B out, it can be used in place of a transponder because it operates with traditional radar and TCAS, in addition to providing the function of ADS-B out. Actually, 1090ES ADS-B is a transponder, but has "extended squitter," meaning it sends the additional data required for ADS-B. The reason is that TCAS still depends on transponders (or 1090ES ADS-B). So I don't think you can really "skip ahead" to ADS-B out and avoid installing a transponder, unless it's 1090ES. Check me on this, but this was my reference: https://www.faa.gov/nextgen/programs/adsb/faq/#21

MPerkins is correct. What I was thinking was it would be worth doing the work (or at least laying the ground work so to speak) during construction versus having to tear the airplane apart to make the addition/upgrade. Doing something once is almost always cheaper than doing it twice.