Copies of FAA AD 90-15-07 may be obtained by contacting Mr Sam Lovell, Airplane Certification Office, FAA, South-west Region, Fort Worth, Texas, 76193- 0150. Telephone (817) 624-5159; Copies of the AAR Oklahoma Inc. Service Information Letter 5-90-1 dated June 7 1990 referred to in the FAA AD may be obtained from AAR Oklahoma Inc., 6611 S. Meridian Avenue, PO Box 59100, Oklahoma City, Oklahoma 73159. Copies of both these Documents may also be viewed at local Civil Aviation Authority (CAA) Field Offices or the CAA Head Office, Continuing Airworthiness Documentation Section, Alan Woods Building, 25 Constitution Avenue, Canberra City ACT.