Final answer:
An aircraft flying IFR on Designated Routes or Over Designated Areas requires a fuel reserve of 30 minutes for day operations and 45 minutes for night operations.
Step-by-step explanation:
In a 705 Operation, an aircraft flying IFR (Instrument Flight Rules) on Designated Routes or Over Designated Areas defined in the Commercial Air Service Standards requires a fuel reserve of 30 minutes for day operations and 45 minutes for night operations.
This fuel reserve is necessary to account for any unexpected delays or diversion to an alternate airport due to weather or other factors. It ensures that the aircraft has enough fuel to safely reach its destination and allows for additional flying time if needed.
For example, if a flight is scheduled to take 3 hours, it would require a fuel reserve of 30 minutes for a total fuel requirement of 3 hours and 30 minutes.