Given a pressure altitude of 6,000 ft, a temperature of +13°C, and 2,500 RPM with 23'' MP, what is the maximum available flight time?

To determine the maximum available flight time under the given conditions, it is essential to understand how pressure altitude, temperature, RPM, and manifold pressure (MP) influence engine performance and fuel consumption.

In this scenario, the pressure altitude is 6,000 feet, which indicates a lower air density compared to sea level. The temperature of +13°C suggests that the temperature is relatively moderate; however, it may still be warmer than the standard atmosphere at that altitude, affecting engine efficiency. At 2,500 RPM and 23 inches of manifold pressure, the engine operates at a specific power setting which balances power output and fuel usage.

The maximum available flight time can be calculated by exhaustively considering the aircraft's fuel flow at the specified mixture settings for efficiency in cruise flight. This will take into account the avionic and aerodynamic parameters alongside the fuel saturation limits based on the given conditions.

The option indicating 5 hours and 12 minutes reflects a calculated optimal long-range cruise setting that aligns well under less than standard atmospheric conditions at that altitude. The energy produced at this RPM/MAP configuration allows for sustained engine operation without creating unnecessary drag or fuel flow, maximizing the endurance of the flight.

Thus, choice B accurately represents the maximum available flight time based