AIRWORTHINESS DIRECTIVE
CAA-AD-4-088/98
Date of issue: November 27, 1998
HELICOPTER - HYDRAULIC RELIEF VALVE - REPLACEMENT
Applicability: Applies to Bell Helicopter Textron Canada (BHTC) Model 206L-4 helicopters, serial numbers 52001 through 52208.
Effective date: December 31, 1998
Compliance : Required as indicated in TC AD CF-98-34
Remarks: Where applicable, the requirements of this AD must be integrated into the Aircraft´s Logbook(s). Address inquiries concerning this AD to: Civil Aviation Authority, Airworthiness Division, Ruzyne Airport, 160 08 Prague 6, Czech Republic, tel: 420 2 324086, fax: 420 2 364112.
Ing. Pavel MATOUŠEK
Director of Airworthiness Division, CAA CZ
Transport Canada Civil Aviation, No.: CF-98-34, Date: 10 September 1998
AIRWORTHINESS DIRECTIVE
THE FOLLOWING AIRWORTHINESS DIRECTIVE (AD) MAY BE APPLICABLE TO AN AIRCRAFT, WHICH OUR RECORDS INDICATE IS REGISTERED IN YOUR NAME. ADs ARE ISSUED PURSUANT TO CANADIAN AV/AT/ON REGULAT/ON (CARI 593. PURSUANT TO CAR 605.84 AND THE FURTHER DETAILS OF CAR STANDARD 625. APPENDIX H, THE CONTINUING AIRWORTHINESS OF AN AIRCRAFT IS CONTINGENT UPON COMPLIANCE WITH ALL APPLICABLE ADs. FAILURE TO COMPLY WITH THE REQUIREMENTS OF AN AD MAV INVALIDATE THE FLIGHT AUTHORIZATION OF THE AIRCRAFT. ALTERNATIVE MEANS OF COMPLIANCE SHALL BE APPLIED FOR IN ACCORDANCE WITH CAR 605.84 AND THE ABOVE-REFERENCED STANDARD.
CF-98-34 BELL
Applies to Bell Helicopter Textron Canada (BHTC) Model 206L-4 helicopters, serial numbers 52001 through
52208.
Compliance is required within the next 300 hours air time, but not later than 31 December 1998, unless already
accomplished.
A manufacturing defect was found on hydraulic relief valve P/N 206-076-036-101. This defect could lead to an
intermittent loss of hydraulic pressure to the flight controls. Replacement of all original valves with the new
ones P/N 206-076-036-105 is therefore necessary. BHTC Alert Service Bulletin (ASB) 206L-98-111 refers.
To ensure proper functioning of the flight controls, replace the hydraulic relief valve P/N 206-076-036-101
with the new one P/N 206-076-036-105, as outlined in BHTC ASB 206L-98-111 dated 24 July 1998 or later
revision approved by the Director, Aircraft Certification, Transport Canada.
This directive become effective 23 October 1998.
For Minister of Transport
M.J. Martin
Acting Chief, Continuing Airworthiness
For further information contact a Transport Canada Centre, or Mr. Bogdan Gajewski, Continuing
Airworthiness, Ottawa, telephone (613) 952-4450, facsimile (613) 996-9178 or e-mail gajewsb@tc.gc.ca.