Please click on the links below to view the FAQ answers.
What are the rules for Experimental aircraft on Transponder, Altimeter,
Altitude Encoder and Static System checks?
If you have a transponder installed in your aircraft,
you must comply with the testing requirements. The requirements of 14 CFR
91.215, 91.217, and 91.411 apply to all aircraft with such equipment installed,
regardless of certification category.
You must also comply with 91.205 and 91.411 if you fly IFR.
Are CFR Parts 91 & 43 applicable to Experimental Aircraft?
Your aircraft Ops Spec requires that the aircraft be operated in accordance with Part 91 as applicable. Part 91 then directs
you to Part 43 Appendix E & F for the testing requirements. So in this case, Part 43 does apply to experimental aircaft.
What inspections are required
for VFR operations?
The aircraft transponder must be certified every 24 months in accordance with the requirements of
CFR. 91.413. Transponder testing is accomplished in accordance with Part 43 Appendix F.
Note: For new certifications or if the encoder or altimeter
has been replaced, a Data Correspondence Check must be accomplished to ensure
the altitude data transmitted to ATC corresponds
to within 125 feet of the altimeter normally used to maintain flight
altitude per CFR 91.217.
What inspections are required for IFR operations?
In addition to the 24 month transponder check, if you fly your aircraft IFR, you must comply
with the pitot/static test requirements called out in 14 CFR 91.411. As with
transponders, this regulation applies to all aircraft, regardless of
certification category. These tests include certifying the altimeter and altitude encoder and checking the static system for leaks.
Who can perform these inspections?
With few exceptions, only an FAA Certified Repair Station (CRS) with the appropriate ratings may perform the
inspections required by CFR 91.411 and 91.413.
Can a builder with a repairman certificate for the aircraft he built perform his own altimeter,
static or transponder certifications?
The FAR’s authorize the "manufacturer" of the
aircraft to conduct the tests However, the builder of an amateur-built aircraft
does not meet the FAA’s definition of a manufacturer. The FAA, in Order 8130.2,
defines a manufacturer as a Production Approval Holder (PAH). Some examples of a
PAH would be the holder of a Production Certificate (PC), a Parts Manufacturing
Authority (PMA), and Technical Standards Order Authorization (TSOA). An amateur
builder does not fit this definition. Thus, the amateur-builder cannot perform
the transponder and pitot/static tests on his/her homebuilt.
If I remove my transponder and re-install it do I
have to repeat the 91.413 test? How about if I replace the transponder with a
newer model or a repaired (yellow tagged) unit, do I have to repeat the 91.413 tests?
From AC43-6B: Removal and Replacement. Removal and replacement of transponder units,
subsequent to testing a system in accordance with § 91.413, will not invalidate the test results. A
repaired or replacement transponder may be installed without repeating § 91.413 testing;
however, a manufacturer’s minimum performance test will be performed before return to service.
Any time the aircraft connections to a transponder have been removed and reconnected, each
altitude reporting code line (in the case of the newer aircraft, the digital data bus) must be tested
for integrity of connection. Integrity of connection for systems using a digital data bus to convey
altitude information to a transponder may be verified by successful reporting of a single altitude.
Integrity of connection for systems using Gillham code connections may be verified by
performing an abbreviated correspondence test at the test points of Appendix 1, Table 1 using the
installed automatic pressure altitude encoding device or through the use of an encoder substation
test unit capable of simulation of the Appendix 1, Table 1 altitudes.
How long does it
take to complete an IFR Certification?
IFR Certifications on a single engine non pressurized aircraft typically take around 4 hours to complete.
For a pressurized twin with dual Pitot-Static systems it typically takes around 8 hours to complete.
Can you complete the
certification in my hanger or on the ramp?
Yes! I can complete your certification wherever your airplane may be
located. Our mobile repair station has all the necessary tools and equipment to
complete the certification (we do need access to power). We do prefer to do IFR checks at our location where we have all the tools and equipment conveniently located.
Must I be present
while you are certifying my aircraft?
No! You may be there if you like, but I can make arrangements to gain access
to your aircraft if you are not there. I often work with the FBO or maintenance
facility on your airport to make this service as convenient as possible to our
If problems are
found can you fix them?
Yes! As a certified aircraft mechanic if an issue is found, often I can fix it on the
spot with little or no additional aircraft down-time.
It's called a "Pitot-Static" system test, is there a "legal" requirement to check the "Pitot" system?
The term "Pitot-Static" check comes from the pressurized aircraft environment where the static system must be checked at a much higher altitude than
a non-pressurized aircraft. In order to accomplish this test, both the Pitot and Static systems must be brought up (evacuated) together to avoid damaging various
instruments. Therefore, although there is no requirement in the CFR's to check the pitot system, the system must be leak free in order to accomplish the static
system checks. Of course it's a good idea to have a leak free Pitot system to eliminate airspeed errors but there is no requirement in the FAR's to do so.
This same situation arises when accomplishing EFIS testing of Air Data Systems (ADAHRS). The altimeter testing of these systems are accomplished in the aircraft, therefore both
pitot and static systems must be evacuated together to avoid damaging the airspeed sensors so the pitot system must also be leak free.
Is there any difference between Certified, Light Sport, and Experimental aircraft
in the regulatory requirements for altimeter and transponder checks?
No, not for the checks
Is there any difference in the records you provide for a Steam Gauge
Altimeter and EFIS Air Data Computers?
No not really, I identify the altimetry source as “Altimeter” or “Air Data”, but as far as the FAA is concerned they are one and the same.
Is there any difference between Certified, Light Sport, and Experimental in the
regulatory requirements for the records you add to the aircraft's records for completion of the 91.411 and 91.413?
No, same requirements and records apply.
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