What should you do with a bad fuel sample according to guidelines?

Retaining a bad fuel sample and taking another is crucial for several reasons. First, it allows for further testing and verification of the fuel quality. By keeping the sample, you can conduct additional analysis to understand any issues better or confirm if the fuel is truly contaminated or substandard. This could involve sending the sample to a lab for more sophisticated testing.

Moreover, maintaining a record of the bad sample can help in identifying trends in fuel quality or problems related to specific suppliers or batches over time. This practice is essential for ensuring safety and operational effectiveness in aviation, as contaminated or poor-quality fuel can lead to serious mechanical issues during flight.

In contrast, options such as disposing of it immediately do not provide an opportunity for further investigation, while mixing it with good fuel compromises the quality of the good fuel, potentially leading to safety risks. Storing it for future reference without taking any action does not address the immediate need to ensure fuel quality. Retaining the sample while taking new samples addresses safety protocols while allowing for thorough evaluation.