A Yeti Airlines ATR 72-500 plane crashed in Nepal, killing all 72 people aboard. The preliminary report on the accident indicated that the plane’s propellers were found in an unusual “feathered position,” which suggested human error as the possible cause of the crash. The following is an analysis of feathering and its role in aviation safety.
Feathering of Propellers
Feathering of propellers is a crucial part of the checklist that pilots must follow when faced with emergencies such as engine failure or shutdown. It involves changing the pitch or angle of the propeller blades to slice the oncoming airflow in almost parallel motion and avoid hitting the air flatly. This process reduces drag and prevents windmilling of the propellers, which can cause the engine to seize or stop working altogether. Feathering is typically done automatically by the propeller control system, which uses an oil pressure system to change the blade pitch. However, in cases where the control system fails, the pilot must manually feather the propellers using a feathering button or lever in the cockpit.
Possible Causes of Feathering Error
Human error is a possible cause of feathering errors. In cases where the control system fails, the pilot must manually feather the propellers. However, if the pilot is not adequately trained or lacks the experience to handle such a situation, they may make errors in the feathering process. Additionally, factors such as fatigue, stress, and distractions can also affect a pilot’s ability to feather the propellers correctly. In some cases, mechanical failure or damage to the propellers or control system can also cause feathering errors.
Impact on Aviation Safety
Feathering of propellers is an essential safety measure in aviation. It can prevent engine failure, reduce drag, and prevent windmilling of the propellers, which can cause further damage to the engine. However, if not done correctly, feathering can also lead to accidents and fatalities. Proper training and experience are crucial for pilots to handle emergency situations such as engine failure or shutdown. They must be able to follow the checklist accurately and make quick decisions under stress to ensure the safety of the passengers and crew.
