What is a potential hazard of improper fuel storage?

The potential hazard of improper fuel storage primarily revolves around the increased risk of contamination or degradation of fuel quality. When fuel is not stored correctly, it can be exposed to various contaminants such as water, dirt, and biological organisms, all of which can severely impact the integrity of the fuel.

Contamination can lead to issues such as microbial growth, particularly in fuels containing bio-components, resulting in the formation of sludge or other harmful by-products. This can clog filters and fuel lines, and potentially cause engine performance issues or failure. In addition, the quality of the fuel can degrade over time due to chemical reactions, such as oxidation, especially when exposed to air and sunlight. Such degradation diminishes the fuel's performance, reliability, and safety when used in aircraft engines.

In contrast, the other answers suggest outcomes that are either beneficial or unrelated to the risks associated with improper storage. For instance, improved performance, decreased efficiency, and extended shelf life do not realistically occur as a result of poor storage practices. Therefore, the focus on contamination and fuel quality degradation underscores the critical importance of proper fuel storage in aviation safety.