FAA seeks methodology to flag abnormal engine vibrations and broadband signatures

WASHINGTON - The Federal Aviation Administration (FAA) Airport Safety Research and Development section is inquiring to procure for a contractor to perform a study to evaluate engine vibration levels and broadband signatures obtained during development and certification testing and in-service operations in order to develop detection thresholds and alerting strategies.

The FAA notes that multiple engine models from different engine original equipment manufacturers (OEMs) have experienced engine and sometimes aircraft damage events due to engine internal failures like partial blade loss, seal cracks or breaks, or anomalies such as excessive wear due to undetected manufacturing assembly errors which have have led to airline fleet disruptions, airworthiness directives, and NTSB investigations.

These events have been associated with abnormal vibration levels or non-synchronous vibration (NSV) signatures in high pressure or low pressure rotor systems (or sometimes accessory drives) that were identified during the subsequent event investigations - leading to corrective actions after the fact.

The FAA is seeking a contractor to evaluate engine vibration and broadband signatures obtained during development and certification testing and in-service operations in order to develop detection thresholds and alerting strategies.

The contractor must develop a methodology to proactively provide alerts or advisories of abnormal vibration levels and signatures and to prompt maintenance decisions to avoid progression of the condition to a more severe damage level.

The agency says it will entail participation by engine manufacturers that power aircraft that make up large portions of a fleet, like Airbus' A320, A330, and A350 and Boeing's 737, 787, and 777.

The selected contractor will be asked to develop a plan for data gathering and analysis, and then quantify the synchronous and nonsynchronous vibration levels and signatures for engine rotors in high pressure/low pressure sections and gearbox drives), in different flight phases, ambient conditions, engine to engine variation, and normal aging.

The contractor will also identify the vibration level thresholds, signature attributes for synchronous and non-synchronous; and relationships to other engine/aircraft parameters to delineate abnormal conditions from normal (non-failure) conditions. Account for normal transient vibration in events such as bird strike; ice slab ingestion in identifying signature of incipient internal failure, damage, stall/surge/IFSD, potential uncontained release of engine hardware.

For documents and additional information, please visit https://sam.gov/opp/1dae417c3ace487e84a29d6b157c9803/view. The FAA's primary contact for this project is Joseph Szwec, who can be emailed at [email protected].