Suspected Unapproved Parts Details
On 14 April 2022, EASA published the Emergency Airworthiness Directive 2022-0068-E, to mitigate the risks of dual brake systems failures at landing and address the root cause of this unsafe condition at aeroplane level.
Investigation of in-service occurrences determined that the lubricant used in concerned Brake Control Valves (BCV) could freeze and jam the BCV at temperatures 30°C warmer than that of its demonstrated design specifications.
Analyses performed by ELKEM - Lubricant Manufacturer - and SAFRAN AEROSYSTEMS - supplier of the BCV - concluded that the lubricant that caused seizing of the BCVs evidenced contamination by the same hydrocarbon compound.
At time of release of this SUP, the source of contamination remains undetermined and further investigations are needed to delineate the scope of the contamination.
Presently, EASA identified two batches of BLUESIL FLD 308V750 that evidenced altered physical properties, which make those two batches unfit for aviation use. BLUESIL FLD 308V750 batch No. 8274601 - confirmed as manufactured on 02 July 2018 and sold by SILITECH between 01 May 2019 and 30 September 2020 - and batch No. 0274601 - claimed as manufactured on 12 Dec. 2020 and sold by SILITECH between 01 May 2021 and 30 April 2022 - are considered as contaminated and should not be used on any parts or components to be installed on any aircraft.
Recommendation:
Parts that have been produced or maintained with BLUESIL FLD 308V750 batch No. 8274601 or No. 0274601, as supplied by SILITECH respectively, between 01 May 2019 and 30 September 2020, and 01 May 2021 and 30 April 2022, are to be considered unapproved and not eligible for installation on any aircraft.
Maintenance organisations, aircraft owners, operators, independent certifying staff, manufacturers, and parts suppliers are encouraged to identify on their aircraft and in their inventories any parts that have been produced or maintained with aforementioned BLUESIL FLD 308V750 batch No. 8274601 or No. 0274601
If any of these parts is found installed on an aircraft or stored in the inventory, it is recommended to remove and quarantine it, to prevent its (re)-installation. It is recommended that any new information regarding these parts be sent by E-mail to SDM [at] easa.europa.eu
