Specific Service Bulletins (e.g., SB 73-0122) define approved CIS fuels and additives, often requiring specialized inspection if not using standard fuel. 3. Operational Improvements (7B Series)
Working Together Team (WTT) meetings in 2017 focused on fan blade repairs, HPT blade inspections, and addressing fuel leaks. 4. Maintenance Planning & Support
Enhancements to sensor systems to prevent engine stalls, specifically addressing T12 sensing circuits. CFM56-73.rar
Enhancements implemented for increased efficiency and reliability.
Reports of Hydromechanical Unit (HMU) failures caused by corrosion and seizure of the delta P valve when operating on TS-1 fuel. Action: Cleaning, inspection, and repair of affected HMUs. Specific Service Bulletins (e
Software versions designed to keep Variable Bleed Valve (VBV) doors closed at high power to reduce fuel consumption.
Specialized borescope inspections for High-Pressure Compressor (HPC) variable stator vanes to prevent rotor-to-stator contact. Reports of Hydromechanical Unit (HMU) failures caused by
Here is a report summary based on key CFM56-7B operational data and service bulletins: 1.