Endurance refers to the ability of an aircraft to remain in flight for a specific duration, considering factors such as fuel consumption, weight, and power requirements. It is a measure of how long an aircraft can sustain level flight with the available fuel resources. To maximize endurance, the aircraft should fly at an airspeed that minimizes the specific fuel consumption, which typically occurs at the point of minimum drag or maximum lift-to-drag ratio. The formula for endurance () is given by:
Where:
- n is the Propeller Efficiency,
- c is the Specific Fuel consumption in kg/Ws,
- ρ∞ is the density in kg/m3.
- S is the wing area in m2.
- W0 is the Gross weight in kg,
- W1 is the Weight without fuel in kg.
- CL is the Lift Coefficient.
- CD is the Drag Coefficient.