What are the recommended IAS and EPR settings for holding under Operating Conditions O-5?

In determining the appropriate IAS (Indicated Airspeed) and EPR (Engine Pressure Ratio) settings for holding under Operating Conditions O-5, the correct combination is based on specific aerodynamic and performance criteria designed for efficient flight during holding patterns.

The selection of 218 knots and 1.27 EPR as the recommended settings aligns with standard operating procedures that optimize fuel efficiency while maintaining adequate speed and thrust for the aircraft's weight and environmental conditions at that stage. Proper IAS is key to keeping the aircraft stable and safely within the desired airspace, and the associated EPR setting ensures that the engines are producing the necessary thrust without excessive fuel consumption, which is critical during holding scenarios where the aircraft may need to maintain altitude and speed for extended periods.

These values are developed based on the specific characteristics of the aircraft in question, along with best practices established within the industry for handling performance in holding patterns. The parameters ensure that pilots and dispatchers can adequately prepare for the holding phases of flight, which is important for operational efficiency and safety in aviation operations.