Among Aerospace Recommended Practices (ARPs) recently adopted by SAE International is ARP 5757, Guidelines for Engine Component Tests. It was developed to provide a standard for substantiation of aircraft engine component airworthiness, according to ARP5757 sponsor Jim Schmohe of GE-Aviation.
“It defines the types of tests and analyses that are required and then goes on to define an acceptable method of demonstrating compliance with each of those requirements,” he said. “ARP5757 documents practices that are currently being used within the industry and have already been accepted by various certification authorities.”
The recommended practice provides a single set of guidelines that is acceptable to all involved in the industry, including manufacturers and the certification approval authorities.
“Component suppliers may use this ARP to develop substantiation plans for new components,” Schmohe said. “Aircraft engine manufacturers may use this ARP in integrating the components substantiation process with that of the overall engine certification plans. And certification agencies may use this ARP as a definition of what can be expected for component substantiation as part of the overall engine certification process.”
The document was produced with input from the FAA, “and plans developed following this ARP should be an acceptable means of compliance with the provisions of 14 CFR 33.21,” said Schmohe. “The plans should also be acceptable for demonstrating compliance with the equivalent requirements from other certification agencies, including Transport Canada and EASA.
ARP5757 is a product of SAE’s E-36 Committee - Electronic Engine Controls.
ARP5891, Achieving Cleanliness Standards for Aircraft Hydraulic Systems during Manufacture, is a product of the SAE A-6 Committee - Aerospace Actuation, Control, and Fluid Power Systems. “This recommended practice will establish more uniform and technically efficient processes for achieving and maintaining system cleanliness levels during the fabrication, manufacture, and assembly of aircraft hydraulic systems,” said sponsor Bob Olsen, formerly of Parker Aerospace Hydraulic Systems Division.
“Experience has shown that in addition to the removal of microscopic contamination, having a formal established plan such as outlined in ARP5891 for flushing has also been instrumental in the early detection of infrequent anomalies such as crossed lines, misdrilled fittings, and large [debris] in lines. Early detection allowed correction of the anomaly at a manufacturing level, where access and repair was easier,” Olsen said.
The product of SAE’s AC-9C Committee - Aircraft Icing Technology, ARP5624, Aircraft Inflight Icing Terminology, provides recommended definitions for terms commonly used in aircraft icing.
“Over time, the field of aircraft icing has evolved a set of terms that are sometimes used in different ways and have different meanings,” said ARP5624 sponsor Gene Addy of NASA’s John Glenn Research Center. “This document is intended to promote uniform usage of the terms and their definitions. The existence of standard terms and definitions will enable clearer and more productive discussions of the issues in aircraft icing and provides a valuable reference for other publications, including other standards publications, on the
“Everyone involved in aircraft icing will be impacted by this publication, including regulatory agencies, airframers, ice-protection-system manufacturers, aircraft engine manufacturers, ice-detection-system manufacturers, and researchers in aircraft icing.”