For IFR operations, what is the minimum fuel requirement for propeller aircraft when an alternate is required?

In IFR operations, when an alternate aerodrome is required, the minimum fuel requirement for propeller aircraft is indeed 45 minutes of fuel at cruise. This regulation ensures that pilots have an adequate safety margin should they need to divert to an alternate airport due to unforeseen circumstances such as weather, air traffic, or aircraft performance issues.

The rationale behind this requirement is rooted in safety and operational planning. The 45 minutes of extra fuel accounts for the potential delays involved in reaching an alternate airport, allowing for any necessary holding patterns or deviations in flight path. It serves as a buffer to ensure that pilots can respond effectively to changes in the flight plan and maintain a safe operation.

This particular requirement highlights the importance of thorough pre-flight planning, which includes assessing weather conditions and potential alternate airports before departure. Understanding these minimum fuel requirements is crucial for pilots to ensure safety and compliance with regulations.