Guidance for the Certification and Continued Airworthiness of PHM System for Aviation

One of the barriers for the wider use of Prognostics and Health Management (PHM) systems in regular usage in commercial aviation has been the need to certify all components and functions related to PHM. Because PHM systems are not entirely like other systems on an aircraft, little guidance has been provided by the authorities or standards development organizations (SDO) in regards to such certification. Additionally, there is a lack of guidance for the continued airworthiness of the PHM system, i.e., rules for monitoring, maintaining, and updating them. We are not even touching on the ever sensitive topic of the need for significant monetary investment in the development, testing, manufacture, and operations of the PHM system, which OEMs are loath to do. However, there is some good news in the offing. One piece of this complex puzzle has recently been solved and in this paper, we will review and report on three events of significant progress which will help with the development and deployment of PHM systems for commercial aircraft. The MPIG (the Maintenance Programs Industry Group, which develops the maintenance guidance commercial aircraft – MSG) published guidance on how a PHM task can replace an approved scheduled maintenance. Next, the FAA (Federal Aviation Administration) published an advisory circular laying out the requirements for what an end-to-end PHM system needs to comply with to be deployed on aircraft certified in the US. But even more critically, the SAE’s E-32 (Propulsion Health Management) technical committee published a short guidance on how to certify a PHM system – and any required ground support equipment – on an engine. The HM-1 (Integrated Vehicle Health Management) committee later updated this guidance to include the entire vehicle. With these three recent developments, one part of getting PHM systems on aircraft is made easier. Other challenges – such as justifying them financially – still remain, but it will be harder to argue that the certification and continued airworthiness authorities are not in favor of employing PHM systems in commercial aviation.