Airplane IFR Legal?
Reprinted with permission from FAA Aviation News
you know? In today's GPS world, do you still think about using the VOR
navigation system anymore? Most IFR approved GPS systems installed today were
approved under Technical Standard Order (TSO)-C129a for supplemental use. This
supplement use limitation requires alternate navigation equipment to be
available onboard the aircraft. As noted in the Aeronautical Information Manual
(AIM), as long as your GPS uses RAIM for integrity monitoring, you don't have to
be actively monitoring your alternate navigation equipment, but if you lose RAIM
or if RAIM is predicted to be lost, you must use your alternate equipment. That
other equipment might be your VOR. If you have VOR capability, and most
airplanes that file instrument flight rules (IFR), probably have at least one
onboard, when was the last time you checked its accuracy? More importantly, if
you did check its accuracy, did you enter the required check correctly in a
reliable record? Of if someone else made the entry, is it correct? If you rent
the aircraft you fly, do you routinely check its paperwork for currency? No, I
am not talking about the required 24-month checks for its transponder and static
system, as appropriate. Nor am I talking about the annual inspection of its
emergency locator transmitter (ELT), if so equipped. I am asking if you check
that its annual inspection is current. Do you know if the aircraft has to have a
100-hour inspection? If so, is the 100-hour inspection current? Can a 100-hour
inspection cover a 105-hour period? Is so, how? If the aircraft has an
FAA-approved IFR GPS installed, does it have a current database if you use it
IFR? If so, was a proper record made of the data base installation? Finally, if
the aircraft is legal, are you legal to be pilot in command?
are important questions. I think most of us tend to forget the important issues
involved in these questions. Obviously, flight safety is the most important.
However, failure to properly record the results of these inspections can result
in enforcement actions against the pilot in command for operating a
non-airworthy airplane, as well as exposing the aircraft owner or operator to
possible enforcement action as well as possible insurance problems in the event
of an accident.
researching the proper format for recording a VOR operational check, which is
found in Title 14 Code of Federal Regulations (14 CFR) '91.171, VOR equipment
check for IFR operations, I thought this would be a good time to review the VOR
requirements for operating a civil aircraft under IFR using the VOR navigational
system. In describing how a VOR system can be checked, subsection (2) of that
regulation states, 'Has been operationally checked within the preceding 30 days,
and was found to be within the limits of the permissible indicated bearing error
set forth in paragraph (b) or (c) of this section.'
rule then lists the permissible errors. In summarizing those errors, at the
departure airport using an approved radiated VOR test signal or designated
ground test point, a maximum error of plus or minus four degrees. A maximum of
plus or minus six degrees of error is permissible using an airborne procedure as
outlined in the rule. Using the procedure outlined in the regulation for
checking one independent VOR receiver against a second unit in the aircraft
permits a maximum of plus or minus four degrees as acceptable. The regulation
provides complete details for doing the respective type of tests. [The
appropriate FAA Airport/Facility Directory for your area lists VOR receiver
checkpoints and VOR Test Facilities (VOT) you can use for the checks.]
key to your use of an aircraft using a VOR system for IFR flight is contained in
subsection (d) of the rule. That subsection states in part, 'Each person making
the VOR operational check, as specified in paragraph (b) or (c) of this section,
shall enter the date, place, bearing error, and sign the aircraft log or other
record.' If a test signal is used as part of the test, there is a record
requirement for the test signal.
there is an FAA-approved IFR GPS installed in the aircraft, do you know who is
authorized to update the database? Are you? Once the database is updated, do you
know how to check if the signoff was done correctly? If not, you might want to
review 14 CFR parts 43. The authority to update the GPS data base is contained
in Appendix A to Part 43, Major alterations, major repairs, and preventive
maintenance, subsection (c) Preventive maintenance (32). Subsection 32 says,
'Updating self-contained, front instrument panel-mounted Air Traffic Control (ATC)
navigational software data bases (excluding those of automatic flight control
systems, transponders, and microwave frequency distance measuring equipment (DME))
provided no disassembly of the unit is required and pertinent instructions are
provided. Prior to the unit's intended use, an operational check must be
performed in accordance with applicable sections of part 91 of this chapter.'
43 explains who may conduct the operational check and how the results of that
check must be recorded. The following are excerpts from part 43. Anyone
interested in performing any of work outlined in part 43 must review the entire
contents of the rule to ensure compliance. These excerpts are only intended to
provide a quick overview of the rule. If you are a sport pilot or the work
involves a light-sport category aircraft, you need to review the rules that
apply to sport pilots or light-sport aircraft.
Can a pilot perform preventive maintenance?
Yes. 'The holder of a pilot certificate issued under Part 61 may perform
preventive maintenance on any aircraft owned or operated by that pilot which is
not used under Part 121, 129, or 135.'
Q. What is involved in approving an aircraft for return to service after
performing preventive maintenance?
Section 43.5, Approval for return to service after maintenance, preventive
maintenance, rebuilding, or alteration, states in part, 'No person may approve
for return to service any aircraft, airframe, aircraft engine, propeller, or
appliance, that has undergone maintenance, preventive maintenance, rebuilding,
or alteration unless'
(a) The maintenance record entry required by Sec. 43.9 or Sec. 43.11, as
appropriate, has been made.'
Who can approve an aircraft to return it to service?
Sec. 43.7, Persons authorized to approve aircraft, airframes, aircraft engines,
propellers, appliances, or component parts for return to service after
maintenance, preventive maintenance, rebuilding, or alteration, states in part,
'A person holding at least a private pilot certificate may approve an aircraft
for return to service after performing preventive maintenance under the
provisions of Sec. 43.3(g).' Section 43.7(g) and (h) explain what sport pilots
and holders of a repairman certificate (light-sport aircraft) with a maintenance
rating may do concerning light-sport aircraft.
What must the required record contain?
Sec. 43.9, Content, form, and disposition of maintenance, preventive
maintenance, rebuilding, and alteration records (except inspections performed in
accordance with part 91, part 123, part 125, Sec. 135.411(a)(1), and Sec.
135.419 of this chapter), states in part, (a) Maintenance record entries. Except
as provided in paragraphs (b) and (c) of this section, each person who
maintains, performs preventive maintenance, rebuilds, or alters an aircraft,
airframe, aircraft engine, propeller, appliance, or component part shall make an
entry in the maintenance record of that equipment containing the following
information: (1) A description (or reference to data acceptable to the
Administrator) of work performed. (2) The date of completion of the work
performed. (3) The name of the person performing the work if other than the
person specified in paragraph (a)(4) of this section. (4) If the work performed
on the aircraft, airframe, aircraft engine, propeller, appliance, or component
part has been performed satisfactorily, the signature, certificate number, and
kind of certificate held by the person approving the work. The signature
constitutes the approval for return to service only for the work performed.
Although the above information may be more than you wanted to read, the
information provides the regulatory basis for performing the required
operational checks for VOR and installing a data update to a GPS system.
For more information about
all types of repairs, you should check the various appendixes to part 43, which
define what are major repairs, major alterations, preventive maintenance, and
the various types of inspections. Part 43 also provides definitions of the
various types of maintenance and who is authorized to perform that maintenance.