A fuel sample should be taken prior to the __________ of the day.

• A. 1st Flight
• B. First Flight
• C. Start of Day
• D. Beginning of Day

Answer: (A)

The key idea is to test the fuel before any flight operations begin for that day, specifically before the first flight. Taking the sample at that moment ensures you’re checking the fuel that will be used for the initial flight, catching any water, sediment, or contaminants before the aircraft takes off. If you wait until later in the day, changes can occur due to fueling, handling, or time, and the sample may not reflect what’s in the system for the first flight. The phrasing used in procedures is the first flight of the day, which is the precise moment the test should occur; terms like start of day or beginning of day are too vague, and the wording differences like 1st Flight versus First Flight are stylistic, but the important point is sampling before the first flight.