Specific Fuel Consumption Given Preliminary Endurance For Jet Aircraft Calculator

Formula Used:

\[ c = \frac{LD_{max} \times \ln\left(\frac{W_{L,beg}}{W_{L,end}}\right)}{E} \]

Maximum Lift-to-Drag Ratio:

Weight at Start of Loiter Phase:

Weight at End of Loiter Phase:

Endurance of Aircraft:

seconds

Specific Fuel Consumption:

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Specific Fuel Consumption?

Specific Fuel Consumption is a characteristic of the engine and defined as the weight of fuel consumed per unit power per unit time. It's a crucial parameter for evaluating aircraft engine efficiency and performance.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ c = \frac{LD_{max} \times \ln\left(\frac{W_{L,beg}}{W_{L,end}}\right)}{E} \]

Where:

\( c \) — Specific Fuel Consumption (kg/s/W)
\( LD_{max} \) — Maximum Lift-to-Drag Ratio
\( W_{L,beg} \) — Weight at Start of Loiter Phase (kg)
\( W_{L,end} \) — Weight at End of Loiter Phase (kg)
\( E \) — Endurance of Aircraft (seconds)

Explanation: This formula calculates the specific fuel consumption based on the maximum lift-to-drag ratio, weight change during loiter phase, and aircraft endurance.

3. Importance of Specific Fuel Consumption Calculation

Details: Accurate specific fuel consumption calculation is essential for aircraft performance analysis, fuel efficiency optimization, and flight planning. It helps in determining the most efficient operating conditions for jet aircraft.

4. Using the Calculator

Tips: Enter maximum lift-to-drag ratio, weight at start and end of loiter phase in kg, and aircraft endurance in seconds. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the significance of maximum lift-to-drag ratio?
A: The maximum lift-to-drag ratio represents the most efficient aerodynamic configuration of an aircraft, where it produces the maximum lift with the minimum drag.

Q2: Why use natural logarithm in the formula?
A: The natural logarithm accounts for the exponential nature of fuel consumption relative to weight change during the loiter phase.

Q3: What is typical specific fuel consumption for jet engines?
A: Typical values range from 0.0001 to 0.0003 kg/s/W for modern jet engines, depending on the engine type and operating conditions.

Q4: How does weight affect specific fuel consumption?
A: Higher aircraft weight generally increases fuel consumption, but specific fuel consumption measures the efficiency relative to power output.

Q5: Can this formula be used for all aircraft types?
A: This formula is specifically designed for jet aircraft during loiter phase calculations and may not be directly applicable to other aircraft types or flight phases.