Airworthiness and Inoperative Equipment Under 14 CFR Part 91

Many pilots struggle with the regulations and procedures to follow when a preflight inspection or other before-takeoff check reveals a burned-out position light, a non-functional autopilot, or other inoperative equipment. Here’s a basic guide to help you through the thicket of FAA regulations and policies.

This discussion assumes you are operating a typical light GA aircraft under 14 CFR Part 91 and you’re not using a minimum equipment list (MEL). MEL are typically available only for multiengine and large aircraft, and they’re most often used in commercial operations. Note also that as of November 3, 2017, AC 91-67 – Minimum Equipment Requirements for General Aviation Operations Under FAR Part 91, has been canceled, pending a revision that “align[s] with the latest ICAO guidance.”

Before you begin the preflight inspection, review 14 CFR §91.7 Civil Aircraft Airworthiness:

§91.7 Civil Aircraft Airworthiness
(a) No person may operate a civil aircraft unless it is in an airworthy condition.

(b) The pilot in command of a civil aircraft is responsible for determining whether that aircraft is in condition for safe flight. The pilot in command shall discontinue the flight when unairworthy mechanical, electrical, or structural conditions occur.

Simply put, as PIC, you–not your mechanic, or the FBO from which you rent an airplane, or the partner(s) with whom you share an aircraft–are responsible for determining whether the aircraft you’re about to fly is legally airworthy and safe to operate.

CessnaPreflight

Assume that during the preflight inspection, you discover that one of the wingtip position lights has burned out. The key questions to ask are:

  • Can you fly the airplane?
  • How can you comply with the applicable FAA regulations?

Many pilots think that such minor malfunctions require nothing more than recalling the required equipment regulations for day or night, VFR or IFR flight (14 CFR §91.205), and, if necessary, putting an “inoperative” sticker near the appropriate switch or gizmo before taking off.

InopLightSticker

The proper procedure, however, involves methodically tracing your way through several FAA regulations and references, including the aircraft flight manual (AFM) and associated aircraft documents.

Key FAA Regulations (14 CFR Part 91) and Documents

  • §91.7 Civil Aircraft Airworthiness
  • §91.205 Powered civil aircraft with standard category U.S. airworthiness certificates: Instrument and equipment requirements
  • §91.213 Inoperative instruments and equipment
  • §91.405 Maintenance required
  • Aircraft approved flight manual (AFM) or operating handbook (POH)
  • Applicable STC supplements
  • Aircraft Type Certificate Data Sheet (TCDS)

The process you must follow is described in §91.213 (PDF flow chart here). You are allowed to continue with the flight provided:

§91.213

(2) The inoperative instruments and equipment are not—

(i) Part of the VFR-day type certification instruments and equipment prescribed in the applicable airworthiness regulations under which the aircraft was type certificated;

(ii) Indicated as required on the aircraft’s equipment list, or on the Kinds of Operations Equipment List for the kind of flight operation being conducted;

(iii) Required by §91.205 or any other rule of this part for the specific kind of flight operation being conducted; or

(iv) Required to be operational by an airworthiness directive

(3) The inoperative instruments and equipment are—

(i) Removed from the aircraft, the cockpit control placarded, and the maintenance recorded in accordance with §43.9 of this chapter; or

(ii) Deactivated and placarded “Inoperative.” If deactivation of the inoperative instrument or equipment involves maintenance, it must be accomplished and recorded in accordance with part 43 of this chapter; and

(4) A determination is made by a pilot, who is certificated and appropriately rated under part 61 of this chapter, or by a person, who is certificated and appropriately rated to perform maintenance on the aircraft, that the inoperative instrument or equipment does not constitute a hazard to the aircraft.

Here’s a flow chart that outlines the basic process described in §91.213.

InopEquipment-02.jpg

Procedure for dealing with inoperative equipment under 14 CFR Part 91

Throughout the following discussion, note that if the defective or inoperative item is required at any of the decision points, maintenance or obtaining a ferry permit (technically a Special Flight Permit) is required before you can fly.

Begin by determining whether inoperative item is required under the basic regulations for VFR or IFR flight during the day or night (§91.205), including key engine instruments, altimeter, airspeed indicator, magnetic direction indicator, and so forth. Operations at night and under IFR (regardless of prevailing weather conditions) require additional instruments and equipment, such as lights (night) and radios and gyroscopic instruments (IFR).

If the item isn’t specifically listed in §91.205(a)-(d), next determine if it’s required by the AFM/POH equipment list or kinds of operations list (examples below).
C172-EquipmentList-01

C172-EquipmentList-02

DA40-KOA.jpg

DA40-OperationalEquipment-01.jpg

If the item isn’t required by those equipment lists, or if you have an old AFM/POH that doesn’t include equipment lists, next confirm that the item is not required by the aircraft’s type certificate data sheet (TCDS). You can download PDF versions of TCDS from the FAA website, here. These data sheets are usually long and not easy to read, but you can search the PDF for your aircraft to help you locate specific model/serial numbers or items.

C172S-TCDS.jpg

If the item isn’t required by the TCDS, review any STC supplements that apply to your aircraft. For example, if you’ve installed new avionics or electronic instruments in the panel, the STC under which that equipment was installed may contain specific limitations, such as additional sources of electrical power.

GarminSTC.jpg

G500 AFMSupplement-02

Next, you must confirm that the item isn’t required by an airworthiness directive (AD). You can find ADs on the FAA website, here. Again, ADs can be difficult to parse. If you have questions, it’s best to consult a maintenance technician. Aircraft type and owner clubs are also good sources of information about ADs.

If you’ve answered “no” at each step of the process, you can proceed–but you must follow the proper procedure to deactivate or remove and then placard the item. And you must record the discrepancy and action taken in an appropriate record (§91.405 and §43.11).

Options at this point include disabling a switch, pulling and collaring a circuit breaker, or removing the equipment following the appropriate procedure. If the inoperative item is controlled by anything other than a simple switch, it’s best to consult a maintenance technician.

Finally, as PIC, you must determine that the aircraft is safe to operate under the conditions expected for the flight.

Note that you can’t continue to operate indefinitely with inoperative/defective equipment. See §91.405(c) and the De Joseph letter (2017) from the FAA chief counsel. In general, at the next required inspection the item must be repaired, replaced, or removed and the action properly documented by a maintenance technician.

FAA-DeJosephLetter-02

The process described here is cumbersome, especially when you’re away from your home airport without easy access to references and technical advice.

But here’s a good rainy-day project. Create a list of equipment in your aircraft that isn’t clearly required by §91.205 for a typical day or night VFR flight, such as lights, avionics, accessories (seats, cabin heat, power plugs, speakers, etc.). Follow the flow chart, consult the resources described here, and note whether those items would be necessary for a flight under those circumstances.

If you fly IFR, add or note the equipment, beyond the basics in §91.205, that is required by the documents for your aircraft–regardless of the weather–to operate under those rules.

Keep those lists in your aircraft (or on your tablet or phone) so that you can quickly and easily determine whether you can proceed.

Additional References and Resources

FAA Proposes Significant Rule Changes

On May 12, 2016, FAA published Regulatory Relief: Aviation Training Devices; Pilot Certification, Training, and Pilot Schools; and Other Provisions in the Federal Register.

The final rule, which includes several changes from the NPRM, was published June 27, 2018. More details here.

The proposed rule includes many significant changes to 14 CFR Parts 61 and 91 of interest to pilot and flight instructors.

 This rulemaking would relieve burdens on pilots seeking to obtain aeronautical experience, training, and certification by increasing the allowed use of aviation training devices. These training devices have proven to be an effective, safe, and affordable means of obtaining pilot experience. This rulemaking also would address changing technologies by accommodating the use of technically advanced airplanes as an alternative to the use of older complex single engine airplanes for the commercial pilot training and testing requirements…Finally, this rulemaking would include changes to some of the provisions established in an August 2009 final rule. These actions are necessary to bring the regulations in line with current needs and activities of the general aviation training community and pilots.

The November/December 2017 issue of FAA Safety Briefing indicates that the new rules will be published in December 2017: “With another new rulemaking effort in the works, expected in December 2017, the FAA proposes to allow pilots to accomplish instrument currency pilot time in a FFS, FTD, or ATD without an instructor present to verify the time, as well as allow ATD time to accomplish instrument currency requirements to be identical to the tasks and requirements described for an aircraft, FFS, or FTD.”

As of early May 2018, however, the FAA has not published the final rule in the Federal Register. The proposal remains in limbo.

In particular, the changes would:

  • Make it easier to maintain instrument currency using training devices
  • Allow the use of technically advanced aircraft (TAA), not just “complex” (i.e., aircraft with retractable landing gear) for training and practical tests for the commercial pilot and certified flight instructor certificates

For example, one proposed change would allow an instrument-rated pilot to use an approved aviation training device (ATD), flight training device (FTD), or full flight simulator (FFS) to fly approaches and other tasks to maintain IFR currency without having an instructor present. Currently, pilots who perform instrument recency experience requirements in an aircraft are not required to have an authorized instructor present to observe the time. Rather, the pilot can perform the required tasks in actual instrument conditions or in simulated instrument conditions with a safety pilot on board the aircraft. A pilot who accomplishes instrument recency experience in an FFS, FTD, or ATD, however, must have an authorized instructor present to observe the time and sign the pilot’s logbook. 14 CFR 61.51(g)(4).

In revising § 61.57 in the 2009 final rule to include the option of using ATDs for meeting instrument recency experience, the preamble indicated that the FAA did not intend for an authorized instructor to be present during instrument recency experience performed in an FSTD or an ATD. It stated: “[A] person who is instrument current or is within the second 6-calendar month period * * * need not have a flight instructor or ground instructor present when accomplishing the approaches, holding, and course intercepting/tracking tasks of § 61.57(c)(1)(i), (ii), and (iii) in an approved flight training device or flight simulator.” 74 FR 42500, 42518. In 2010, the FAA issued a legal interpretation  [8] stating that, based on the express language in § 61.51(g)(4), an instructor must be present in order for a pilot to accomplish instrument recency experience in an FSTD or ATD. That interpretation acknowledged, however, that the FAA had indicated in the 2009 preamble some intention to change the requirement but that the change was not reflected in the regulation.

The FAA is proposing to amend § 61.51(g) by revising paragraph (g)(4) and adding a new paragraph (g)(5) to allow a pilot to accomplish instrument recency experience when using an FAA-approved FFS, FTD, or ATD—just as he or she might do when completing instrument recency experience in an aircraft—without an instructor present. Because instrument recency experience is not training, the FAA no longer believes it is necessary to have an instructor present when instrument recency experience is accomplished in an FSTD or ATD. An instrument-rated pilot has demonstrated proficiency during a practical test with an examiner. It can be expensive to hire an instructor to observe a pilot performing the instrument experience requirements solely to verify that the instrument recency experience was performed. [9] As noted above, practice in an ATD has the distinct advantage of pause and review of pilot performance not available in an aircraft.

As with instrument recency experience accomplished in an aircraft, the pilot would continue to be required to verify and document this time in his or her logbook. The FAA is retaining the requirement that an authorized instructor must be present in an FSTD or ATD when a pilot is logging time to meet the requirements of a certificate or rating, for example, under §§ 61.51(g)(4), 61.65 and 61.129.

The FAA proposals would also eliminate much of the confusion about varying time intervals and tasks required when using a training device or simulator to maintain instrument currency.

Currently, under § 61.57(c), to act as pilot in command (PIC) of an aircraft under instrument flight rules (IFR) or in weather conditions less than the minimums prescribed for visual flight rules (VFR), an instrument-rated pilot must accomplish instrument experience (often described as instrument practice, currency or recency) within a certain period preceding the month of the flight.

If a pilot accomplishes the instrument recency experience in an aircraft, FFS, FTD, or a combination, then § 61.57(c)(1)-(2) requires that, within the preceding 6 months, the pilot must have performed: (1) Six instrument approaches; (2) holding procedures and tasks; and (3) intercepting and tracking courses through the use of navigational electronic systems. [10] If a pilot accomplishes instrument experience exclusively in an ATD, then § 61.57(c)(3) requires that, within the preceding two months, the pilot must have performed the same tasks and maneuvers listed previously plus “two unusual attitude recoveries while in descending V ne airspeed condition and two unusual attitude recoveries while in an ascending stall speed condition.” 14 CFR 61.57(c)(3). Section 61.57(c)(3) also requires a minimum of three hours of instrument recency experience when using an ATD, whereas no minimum time requirement applies when using an aircraft, FFS, or FTD to accomplish the instrument experience.

If a pilot accomplishes the instrument recency experience using an ATD in combination with using an FFS or FTD, then the pilot must—when using an ATD—perform the additional tasks but the “look back” period to act as PIC is six months rather than two months. 14 CFR 61.57(c)(5). The FAA stated in 2009 that the more restrictive time limitations and additional tasks were based on the fact that, at the time, ATDs represented new technology.

Since the ATD provisions were added to § 61.57 in the 2009 final rule, the FAA has received numerous inquiries regarding the terms used in the rule and what might be acceptable combinations when using various aircraft or training devices to satisfy the currency requirements. [11]

The FAA is proposing to amend § 61.57(c) to allow pilots to accomplish instrument experience in ATDs at the same 6-month interval allowed for FFSs and FTDs. In addition, the FAA is proposing to no longer require those pilots who opt to use ATDs exclusively to accomplish instrument recency experience to complete a specific number of additional hours of instrument experience or additional tasks (in existing § 61.57(c)(3)) to remain current. As discussed previously, significant improvements in technology for these training devices have made it possible to allow pilots to use ATDs for instrument recency experience at the same frequency and task level as FSTDs. The FAA believes that this proposal would encourage pilots to maintain instrument currency, promote safety by expanding the options to maintain currency, and be cost saving. As proposed, a pilot would be permitted to complete instrument recency experience in any combination of aircraft, FFS, FTD, or ATD.

Pilots training for a commercial pilot certificate with a single-engine-land rating or a certified flight instructor certificate would no longer have to train in a aircraft with retractable landing gear or use such an aircraft on the corresponding practical tests. Instead, FAA proposes to allow the use of technically advanced aircraft (TAA) for those purposes.

Under the current requirements, an applicant for a commercial pilot certificate with airplane category single engine class rating must accomplish 10 hours of flight training in a complex airplane  or in a turbine-powered airplane…In addition, the Commercial Pilot Practical Test Standards for Airplane (as well as the Flight Instructor Practical Test Standards for Airplane) require a pilot to use a complex airplane for takeoff and landing maneuvers and appropriate emergency tasks for the initial practical test for a commercial pilot certificate with an airplane category…

With the prominence of airplanes equipped with glass cockpits (i.e., TAA) in today’s general aviation aircraft fleet, the FAA believes it is appropriate to permit the use of certain TAA to complete the training required in § 61.129(a)(3)(ii) and appendix D to part 141 as well as to meet the requirements of the commercial single engine airplane pilot and flight instructor practical test standards…

This trend toward exclusive production of airplanes with glass cockpits (TAA) is due to an increase in demand for advanced avionics cockpit platforms by general aviation consumers. [39] At the same time, there has been a significant decrease in the production of single engine complex airplanes. [40] The FAA understands the decrease in single engine complex airplane manufacturing is due, at least in part, to newer airframe and power plant technologies that allow for aircraft to achieve higher performance (e.g., airspeed, reduced fuel consumption, etc.) without the manufacturing and maintenance costs associated with a retractable gear system that is characteristic of a complex airplane. Cirrus Aircraft has delivered 5,326 aircraft with this fixed gear configuration as of 2012. [41]

Notwithstanding the previous use of terms such as glass cockpit and electronic flight instrument displays, the FAA is proposing to adopt an updated definition of “technically advanced airplane” in § 61.1 based on the common and essential components of advanced avionics systems equipped on the airplane, including a PFD, MFD and an integrated two axis autopilot. These components would be required in order to ensure the TAA used to meet the aeronautical experience requirements for commercial pilots in § 61.129(a)(3)(ii) and appendix D to part 141, as well as the related practical test standards, as amended, have the necessary level of complexity comparable to the traditional single engine complex airplane.

TAA would be required to include a PFD that is an electronic display integrating all of the following flight instruments together: An airspeed indicator, turn coordinator, attitude indicator, heading indicator, altimeter, and vertical speed indicator. Additionally, an independent MFD must be installed that provides a GPS with moving map navigation system and an integrated two axis autopilot. [44] In general, the pilot interfaces with one or more computers in order to operate, navigate, or communicate. The proposed definition of TAA would apply to permanently-installed equipment and would not apply to any portable electronic device. The FAA recognizes the continuing advancements in aircraft avionics and the need for a pilot to be proficient with modern cockpit equipment and automation. As proposed, the FAA would define the term TAA as an airplane with an electronic PFD and an MFD that includes, at a minimum, a GPS moving map navigation and integrated two-axis autopilot.

In addition to adding a definition of TAA to § 61.1, the FAA is proposing to amend the existing training requirements to permit the use of a TAA instead of a complex or turbine-powered airplane by commercial pilot applicants seeking an airplane category single engine class rating. In addition to the regulatory changes, the FAA would revise the practical test standards for commercial pilot applicants and flight instructors seeking an airplane category single engine class rating.