The Honeywell F125IN turbofan engine is a drop-fit retrofit, superior option for Jaguar re-engining

The F125IN is a high performance, low bypass-ratio turbofan engine that meets the most rigorous requirements of modern light combat and advanced trainer aircraft. The F125IN engine was designed in accordance with U.S. Military specifications and standards, including the USAF’s Engine Structural Integrity Program (ENSIP), MIL-STD 1783.

Maximum Performance
The engine has the highest thrust-toweight ratio in its class and allows unlimited operation at all power ratings. Incorporating a three-stage fan and five-stage axicentrifugal high-pressure compressor, the unique design of the F125IN engine maximizes engine performance while providing exceptional inlet distortion tolerance and stall resistance. With only a single stage of variable geometry at the compressor inlet, the F125IN design also reduces complexity and increases reliability. The Modular, Reliable, High Performance Solution Ready for Jaguar. Axial turbines drive the fan and compressor rotors on concentric co-rotating shafts employing high work single-stage designs. Low HP turbine temperatures ensure long life and inherent growth capability. Substantial thrust growth has been designed specifically for demanding military applications.

Advanced Control
Designed from inception to operate with a Full Authority Digital Electronic Control (FADEC), the engine includes all controls and sensors required for fully automatic operation and unrestricted throttle movement throughout the flight envelope. Pilot workload is significantly reduced through features such as automatic start and ignition sequencing, unrestricted throttle movement, continuous temperature and speed limiting, automatic control of the afterburner, including continuous thrust modulation from max dry thru max reheat, automatic relight after engine or afterburner flameout, and transient fuel and nozzle scheduling to avoid engine surge. The dual FADECs perform continuous diagnostics through built-in test (BIT) and fault-detection/ accommodation logic. Transfers to backup modes of operation are performed automatically with no pilot action required, and with no degradation in engine performance.

Modular Design
The F125IN engine is designed to be truly modular. All modules can be installed or removed from the engine, or interchanged with modules from another engine, without requiring special re-testing, balancing, or shimming. This feature of the engine provides significant maintenance and logistics benefits to the operator, and also facilitates international co-production and support.

Ease of Maintenance
The F125IN includes several features designed to ease maintenance. An integrated Engine Monitoring System (EMS) continuously monitors engine health and tracks life usage in order to alert the operator when a maintenance action is required. This on-condition maintenance philosophy helps to significantly reduce maintenance and down times. The EMS also records important data to be used for performance trend monitoring. EMS health monitoring and diagnostic information is integrated into the technical publications to ensure rapid post flight engine analysis and fault isolation. Engine life records are also automatically captured and transferred to engine maintenance records. Other design concepts such as the elimination of safety wire, the elimination of shimming requirements, easy access to line replaceable units, and excellent boroscope access have been incorporated to simplify maintenance actions.

The F125IN engine is offered with a comprehensive and proven Integrated Logistics Support program. Packages can be tailored to meet the specific requirements of the operator and include Ground Support Equipment (GSE), Logistics Support Analysis (LSA), provisioning and spares management, maintenance training, and technical publications.