Bell guys ? Factory guys ?  

Retirement Index Number (RIN). Components sensitive to operational events, such as torque events or run-on landings, are assigned a maximum RIN number. This number is based on the fatigue damage that results from normal helicopter lifts and takeoffs (torque events) or from run-on landings, whichever applies. New components will begin with an accumulated RIN of zero, which will increase as the helicopter is subjected to torque events or run-on landings. The operator must record the number of torque events or run-on landings, and increase the accumulated RIN as directed. When a component reaches the maximum RIN or retirement flight hours, whichever occurs first, the component must be retired from service

 

 

For every one torque event, you add one RIN to the previous total. A torque event occurs for every takeoff (one takeoff plus the subsequent landing equals one RIN) and every load lift. A load lift (internal or external) may be defined as a sling load, a rescue hoist load or any load that is added to the helicopter while airborne. For example: if an operator performs one takeoff, picks up and drops 10 sling loads, and then lands, he must record 11 torque events.

 

 

For every one run-on landing, you add one RIN to the previous total. A run-on landing is defined as one where there is forward ground travel of the helicopter greater than 3 feet with the weight on the skids.