What are the two most common causes of chafing in aircraft systems?

The leading causes of chafing in aircraft systems primarily stem from a lack of proper tension and the use of inadequate components, making excessive slack and improper fasteners the top contributors. Excessive slack in lines or cables can result in them moving too freely, which may lead to contact with sharp edges or other components, eventually causing wear and chafing.

Moreover, improper fasteners might not secure components effectively, leading to vibration or movement that exacerbates this wear process. This combination means that when lines or cables are not taut or are not held securely in place with the right fasteners, the risk of damaging friction increases significantly.

In contrast, the other options do not address the most direct mechanisms by which components might rub against each other and lead to chafing. Therefore, understanding the significance of maintaining proper tension and secure fastening is crucial for preventing chafing in aircraft systems.