AIRWORTHINESS DIRECTIVE
CAA-AD-4-075/98R1
Replacement CAA-AD-4-075/98
Date of issue: February 04, 2000
ENGINE - FAN DISK - INSPECTION
Applicability: CFM56-3-B1, CFM56-3B-2 and CFM56-3C-1 turbofan engines.
Effective date: March 23, 2000
Compliance: Required as indicated in DGAC AD 1997-298(B) R3.
Remarks: - The compliance of this AD must be recorded in Aircraft Logbook, where applicable the requirements of this AD must be integrated into Aircraft Technical Documentation. Address inquiries concerning this AD to: Civil Aviation Authority, Airworthiness Division, Ruzyne Airport, 160 08 Prague 6, Czech Republic, tel: 420 2 33320922, fax: 420 2 20562270.
Ing. Pavel MATOUŠEK
Director of Airworthiness Division, CAA CZ
DGAC AD ref.: 1997-298(B) R3
CFM INTERNATIONAL
CFM56-3-B1, -3B-2, -3C-1 series turbofan engines
Inspection of fan disk (ATA 72)
1. APPLICABILITY
This Airworthiness Directive applies to CFM56-3-B1, CFM56-3B-2 and CFM56-3C-1 turbofan engines.
2. REASON
Two in service events occurred on fan modules in 1996 which result in a case of a fan blade failure at the root and in another case of a fan disk dovetail crack.
Investigations revealed that wear on fan disk dovetail pressure faces is the main contributor to these events.
In order to prevent the risk to have further cracked fan disks in the fleet, the following conditions are made mandatory.
3. MANDATORY ACTIONS
3.1. Use of ZIP D5460 NS and ZIP D5460 products to lubricate fan blades is no more allowed.
3.2. Perform fan disk inspection respecting method, cycles since new (CSN) and time since new (TSN) indicated in CFM56-3/-3B/-3C SB 72-854 Revision 2 dated November 29, 1999.
3.3. No later than 30 days after the inspection, report the result to CFM INTERNATIONAL.
REF.: Service Bulletin CFM56-3/-3B/-3C SB 72-854 Rev. 2 dated November 29, 1999.
This Revision 3 replaces AD 97-298(B) R2 dated September 09, 1998.
EFFECTIVE DATES:
Original AD: OCTOBER 18, 1997
Revision 1: NOVEMBER 29, 1997
Revision 2: SEPTEMBER 19, 1998
Revision 3: JANUARY 22, 2000