39 ENGINEERING PRODUCT LINE | ENGINEERING AeTR’s understanding of corporate aircraft landing gear systems also results in several options to minimize the system’s total life cycle cost. AeTR can both extend service life and prevent common Beyond Economical Repair (BER) situations that would otherwise result in an expensive replacement. AeTR holds several proprietary FAA-approved repair processes that can not only extend the life of a component, but also save money by eliminating the need to purchase new parts for BER replacement. AeTR engineers have developed the following types of value-added engineered solutions: Alternative / Replacement Parts • Design and produce a part to directly replace a material due to reliability issues, DMSMS issues, high cost, or lead time Repair Scheme • Develop and certify a repair scheme, including the required technical data and/or maintenance manuals, to repair serviceable material in order to avoid scrap / replacement or to extend time on wing Service Life Extension Program (SLEP) • Develop and certify a modification to extend the life limit of an aircraft component; these engineered solutions are then certificated through the US Federal Aviation Administration (FAA) Parts Manufacturing Authority (PMA) • PMA is a FAA approval for the combined design and production of a replacement / alternate part Supplemental Type Certificate (STC) • STC is a certification document issued by the FAA approving a modification to an aircraft, engine or propeller FAA-approved Major Repairs or Alterations via a Designated Engineering Representative (DER & RS-DER) • A DER is a delegate of the FAA administrator, who can review and recommend approval of major repairs or alterations to aircraft and components • A RS-DER is a DER who can also approve Repair Processes (including Maintenance Manuals) to allow multiple uses of a developed repair scheme or alteration ENGINEERING CONT.