CIRCULATED TO ALL RESPONSIBLE

AUTHORITIES OF ICAO CONTRACTING STATES

NOTIFICATION TO FOREIGN AVIATION AUTHORITIES OF REQUIREMENTS MADE MANDATORY BY THE UK CIVIL AVIATION AUTHORITY - ISSUE 3/2001 - ADDENDUM

Please be advised that the Civil Aviation Authority has classified compliance with the following action as mandatory for aircraft on the United Kingdom Civil Register.

CAA AIRWORTHINESS DIRECTIVE       002-03-2001

APPLICABILITY                                       BAE Systems (Operations) BAe 146-100, -200 and -300 Series aircraft.

SUBJECT - DESCRIPTION                        Air Conditioning - To inspect engine oil seals, APU and ECS jet pump and air conditioning pack for signs of oil contamination.

COMPLIANCE - REQUIREMENT (SUMMARY)                        Compliance is required with BAE Systems (Operations) Service Bulletin ISB.21-150.  The Service Bulletin requires inspection of the inside of each air conditioning pack regenerative air ducts and air cycle machine for the presence of oil contamination and the engines and APU for signs of wet oil contamination.  Inspection is required immediately whenever a cabin air quality problem is identified which is suspected of being associated with oil contamination of the air supply from the ECS packs, whether intermittent or persistent.  Effective from 3 April 2001, inspection is required at the next and every subsequent 'A' Check or within a maximum of 500 flights and repeated at a maximum 500 flight intervals.  This action is required because incidents have been reported involving impaired performance of the flight crew.  There is some circumstantial evidence that the events could have been caused by inhalation of an agent(s) resulting from oil and/or oil breakdown products leaking from the engine(s) or APU and contaminating the environmental control system.