Articles
Parts Terminology, by Joel Plake
Parts are sold in a variety of conditions. These conditions indicate the current inspection status of the part, the paperwork that verifies that status, and the price the individual part will command in the market. Following is a listing, standard abbreviation, and description for those conditions:
New (NE) - New parts have been manufactured to an FAA-approved process and through an FAA-approved quality system. The parts have never been run in an engine. They have airworthiness documentation stating that they are "New" or "Manufactured".
New Surplus (NS) - New surplus parts are the same as New parts, but the airworthiness documentation verifying their condition is no longer available. This is typically due to the paperwork filing system of the original purchaser of the parts. Parts in New Surplus condition have all of the manufacturer's markings and can be determined by inspection to not have been engine run. These parts are most often sold with a certification statement from the seller verifying the part's condition.
Overhauled (OH) - Overhauled parts are parts that have been previously installed and run in an engine, but subsequently removed and inspected to the requirements of the overhaul manual. Once inspected and found to meet overhaul manual criteria, an FAA-approved repair station may issue airworthiness documentation stating that the parts meet the requirements for re-installation into an engine at overhaul or any other maintenance visit.
Serviceable (SV) - Serviceable parts are parts that have been previously installed and run in an engine, but subsequently removed and inspected to the requirements of the maintenance manual. Once inspected and found to meet maintenance manual criteria, an FAA-approved repair station may issue airworthiness documentation stating that the parts meet the requirements for re-installation into an engine at any maintenance visit other than an overhaul.
Repairable (RP) - Repairable parts are parts that have been inspected to overhaul or maintenance manual criteria and found to be outside of the limits for re-installation, but for which there is a procedure for repairing the part that will restore it to manual limits. The repair has not yet been performed, but a known repair process is available if required.
As Removed (AR) - As removed parts are parts that have been removed from a running engine, but have not been inspected to the overhaul or maintenance manuals. Before they can be returned to service, they must be inspected and approved by a FAA-certified inspector.
Reject (RJ) - Reject parts are parts that have been inspected to overhaul or maintenance manual criteria and found to be outside of the limits for re-installation, and for which there is no procedure for repairing the parts that will restore it to manual limits. These parts do not meet the requirements for re-installation.
Engine Terminology, by Joel Plake
Engines have many factors that affect their price, perceived value, and use in a specific flying application. Following is a listing, standard abbreviation, and description for the most important factors:
Time Since New (TSN) - This is the total flying hours recorded on an engine for all of the aircraft on which it has been installed.
Cycles Since New (CSN) - This is the total number of takeoff and landing combinations that have been recorded on an engine for all of the aircraft on which it has been installed.
Time Since Overhaul (TSO) - This is the total flying hours recorded on an engine for all of the aircraft on which it has been installed, since its last overhaul.
Cycles Since Overhaul (CSO) - This is the total number of takeoff and landing combinations that have been recorded on an engine for all of the aircraft on which it has been installed, since its last overhaul.
Time Since Hot Section Inspection (TSHSI) - This is the total flying hours recorded on an engine for all of the aircraft on which it has been installed, since its last hot section inspection.
