Summary of Federal Aviation Maintenance Regulations

## Introduction Aircraft maintenance regulations govern how aircraft are maintained, inspected, and documented to ensure continued airworthiness and safety. This guide focuses on maintenance records, inspections, Airworthiness Directives (ADs), and definitions and responsibilities under 14 CFR Part 43 and related FARs. It is written for self-learners preparing for practical maintenance responsibilities or exams. ## Key Regulations and Definitions > **Definition:** The Federal Aviation Regulations (FARs) are the federal laws and rules that govern civil aviation in the United States. > **Definition:** 14 CFR Part 43 describes the requirements for maintenance, preventive maintenance, rebuilding, and alteration of certificated aircraft. ## Who May Rebuild an Engine and Issue Zero-Time Records - Only the **engine manufacturer** or a **repair station approved by the manufacturer** is authorized to rebuild an aircraft engine and issue a zero-time maintenance record. Practical example: If EngineCo manufactures Model A engines, only EngineCo or a repair station with EngineCo approval can rebuild a Model A and certify it as zero-time. ## Progressive Inspections > **Definition:** A progressive inspection is an FAA-approved inspection program allowing the full inspection to be completed over a scheduled period rather than all at once. - Approved by the FAA Flight Standards District Office (FSDO). - Inspections are divided into segments and scheduled so the aircraft need not be grounded for the entire inspection period. Practical example: A 100-hour style inspection might be broken into quarterly segments so that each visit inspects a portion of the checklist; at the end of the schedule the entire inspection scope has been covered. Fun fact: Progressive inspections let operators keep aircraft in service more often by distributing inspection tasks across multiple visits while still meeting FAA-approved standards. ## Maintenance Records and Required Entries - **When to record total aircraft time:** Inspection record entries must include the aircraft total time. - **Transfer of records on sale:** Maintenance records that include the current list of applicable Airworthiness Directives must be transferred with the aircraft when it is sold. Practical application: When selling an aircraft, ensure the buyer receives the maintenance log showing compliance with each AD applicable to the aircraft. ## Fraudulent Entries: Penalties - Making a fraudulent or intentionally false entry in any record or report required to be kept may result in **suspension or revocation of the applicable airman certificate(s)**. Real-world implication: A mechanic falsifying inspection completion risks losing certificates and possible legal consequences. ## Overhaul vs. Rebuilding (Aircraft Engines) > **Definition:** “Overhaul” and “Rebuilt” describe different levels of engine work and testing standards. | Term | Required Standard | Typical Parts Used | Resulting Test Standard | |---|---:|---|---:| | Overhauled | Tested to approved current standards and technical data | New or serviceable parts meeting current specs | Meets current approved standards for serviceability | | Rebuilt | Restored to the same tolerances and limits as a new item | New or old parts brought to new-item tolerances or approved oversize/undersize dimensions | Tested to the limits of a new item; considered equivalent to new for tolerances | - Short summary: Overhaul = tested to current standards; Rebuild = restored and tested to new-item tolerances. Practical example: An overhauled engine may reuse some serviceable components within current limits, whereas a rebuilt engine is brought back to new-item dimensional limits and tested accordingly. ## 100-Hour Inspection Guidance - **Minimum scope and detail checklist location:** FAR Part 43, Appendix D contains the minimum scope and detail for performing a 100-hour inspection. - **Example inspection entry location:** A mechanic can find an e