8A-6314-00

Torque transmission function of 8A-6314-00

The 8A-6314-00 shaft transfers rotational motion from the main gearbox output to the axial cooling fan. This torque transmission keeps the fan running and provides airflow for cooling the engine and main gearbox oil radiators. In service, the shaft operates under variable loads, high rotational speed and vibration typical for helicopter transmission systems. The cardan design allows the shaft to tolerate limited angular misalignment between connected units. This helps reduce stress on the drive line and supports smoother operation when the airframe and equipment mounts move under flight loads.

8A-6314-00 connection to the cooling fan assembly

The 8A-6314-00 cardan shaft is connected to the axial single-stage cooling fan assembly 8A-6311-00, including Series 4 configurations where applicable. This connection is part of the mechanical path that drives the fan impeller. The fan then supplies airflow to the cooling equipment installed in the helicopter. A fault in the shaft, joints or flanged connections can affect fan rotation and may reduce cooling airflow. For this reason, the shaft should be considered together with the fan assembly, main gearbox output interface and related mounting hardware during inspection or replacement.

Aircraft application of the 8A-6314-00 shaft

The 8A-6314-00 fan drive cardan shaft is used on Mi-8 family helicopters and related configurations, including Mi-17, Mi-171 and Mi-172. It is installed in helicopter systems where the cooling fan is mechanically driven from the transmission. Applicability should still be checked against the aircraft parts catalog and the actual installed fan drive system, especially on aircraft that have passed through overhaul or modernization. A visually similar cardan shaft should not be treated as interchangeable unless the designation, connection geometry, rotation direction and system documentation match.

System integration of 8A-6314-00 in helicopter cooling

The 8A-6314-00 works between the main gearbox and the cooling fan as part of the engine and transmission thermal management system. The shaft does not cool the units directly; it drives the fan that creates the required airflow. During operation, this airflow passes through the radiator area and supports heat removal from the oil circuits of the engines and main gearbox. Since the shaft rotates at high speed, balance, joint condition, lubrication condition and secure fastening are important. Excessive play, vibration, damaged splines or worn joints may affect the whole fan drive system.

Identification and ordering of 8A-6314-00

The shaft may be referenced under several designations: 8A-6314-00, 8A-6314-00 and 8A631400. These variants refer to the same fan drive cardan shaft, but the main designation should be matched with the aircraft documentation before ordering. For correct supply, it is useful to confirm the helicopter type, installed fan assembly, shaft condition, completeness and required documentation. If the shaft is requested for replacement, a photo of the installed part, the passport reference and the connected fan assembly number can help avoid selection errors.