The Intricacies of Aircraft Parts Condition Codes: A Deep Dive into AirParts' ATA Classification System

September 25, 2023 by
The Intricacies of Aircraft Parts Condition Codes: A Deep Dive into AirParts' ATA Classification System
Roland Pinto

The aviation industry, a marvel of human engineering and coordination, relies heavily on the quality and condition of its numerous components. Ensuring that each part of an aircraft is in optimal condition is not just a matter of efficiency—it's a matter of safety. AirParts, recognizing the importance of clarity in this domain, has instituted a comprehensive set of condition codes. This article offers an in-depth look into these codes and the broader landscape of aircraft parts procurement.

Before we dive into the meat of the article, we must understand where the basis of these parts condition codes comes from; The Air Transport Association (ATA).

The Importance of the Air Transport Association (ATA) in Aviation

The Air Transport Association (ATA), now known as Airlines for America (A4A), is a trade group that represents the largest airlines in North America. Founded in 1936, the ATA has been instrumental in influencing and shaping policies that promote safe, efficient, and sustainable air travel. The ATA has played a pivotal role in numerous facets of the aviation industry over the years, from advocating for regulatory reforms to establishing standardized practices that ensure consistency and dependability across airline operations.

Standardizing Aircraft Maintenance: The ATA Chapter System

The ATA Chapter System is one of the most significant contributions to the aviation industry made by the ATA. This system was created to standardize aircraft maintenance and repair procedures. The ATA Chapter System provides a standardized method for documenting and referencing aircraft systems and components by classifying various sections of an aircraft into distinct chapters, each with a unique number and title. This standardization is essential for maintenance professionals, manufacturers, and airlines, as it ensures a consistent method for identifying and referring to an aircraft's various elements regardless of its make or model.

Consequences and Advantages of the ATA Chapter System

The aviation industry is profoundly impacted by the ATA Chapter System. It facilitates communication between various stakeholders, from aircraft manufacturers to maintenance personnel, by providing a standard reference. This ensures that when a specific component or system requires attention, its location and purpose are clear. Additionally, the system facilitates training and education, allowing maintenance professionals to seamlessly transmit their skills and knowledge across aircraft varieties. In essence, the ATA Chapter System demonstrates the industry's dedication to safety, efficiency, and uniformity, ensuring that aircraft are maintained to the highest standards regardless of where they are operated.

So, the parts condition codes come from the ATA's creation of standards that have been welcomed by the industry with open arms. There are 

1. NE – NEW – Factory New Parts with Full Traceability

  • Definition: These are pristine, untouched parts straight from the manufacturer.
  • Significance: Representing the pinnacle of quality, these parts come with full traceability, ensuring that their origin and manufacturing conditions are known. They are typically sealed in the original packaging, preserving their condition until use.
  • Application: Ideal for critical components where only the best will do, especially in newer aircraft models.

2. RB – REBUILT – Near-New Condition Parts Rebuilt by OEM or PMA

  • Definition: Used parts restored to their original glory.
  • Significance: These parts undergo a rigorous process where they're disassembled, inspected, repaired, and then reassembled to meet original specifications.
  • Application: Suitable for situations where new parts might be overkill or too expensive, but reliability is still paramount.


  • Definition: Previously used parts that have been refurbished.
  • Significance: They've been restored following stringent OEM procedures, ensuring they meet FAA-approved standards.
  • Application: Ideal for older aircraft models where brand-new parts might not be available or necessary.


  • Definition: New parts that lack the manufacturer's material certification.
  • Significance: They offer the quality of new parts but might come without the official documentation, often making them more affordable.
  • Application: Useful for non-critical components or when operating on a tighter budget.


  • Definition: Used parts deemed fit for service.
  • Significance: They've been inspected and approved for installation, offering a balance between cost and reliability.
  • Application: Great for routine maintenance or replacements where top-tier new parts aren't necessary.


  • Definition: Parts taken off an aircraft without subsequent testing or inspection.
  • Significance: Their condition is unknown, making them a bit of a wildcard in the procurement process.
  • Application: Often used as core replacements or for parts that will undergo thorough testing and possible refurbishment.


  • Definition: Parts taken off an aircraft, inspected by a repair station, and then documented appropriately to show the part has been tested and inspected, found to be defect-free, and usually will come with all traceability and testing paperwork.
  • Significance: The part has been inspected, usually there is no work done to the part, only verification that the part has been checked out.
  • Application: Used to verify the integrity of a part and nothing else.

8. RP – REPAIRED Components, parts, or rotables restored to serviceable condition status through procedures and data acceptable to the Administrator, the manufacturer, and/or the PMA.

9. MO – MODIFIED Components, parts, or rotables altered or modified in accordance with approved data by the Administrator, manufacturer, or PMA.

10. TST – TESTED Components, parts, or rotables inspected, tested, and examined through test procedures approved by the FAA, the manufacturer, or the PMA, ensuring conformity to operating specifications.

Conclusion The aviation industry's complexity is mirrored in the intricate systems governing parts procurement. Understanding AirParts' condition codes is crucial for anyone involved in this sector, ensuring that parts are sourced, maintained, and replaced with the utmost care. As the industry continues to evolve, these condition codes and the practices surrounding them will undoubtedly adapt and evolve, but their core purpose—ensuring the safety and efficiency of flight—will remain unchanged.

You can browse our AirParts Aero Condition Code Page here.