GATE_AE_2027_MOCK_03_Q47
GATE 2027 Aerospace Engineering All-India Master Mock 03 (Flight Dynamics, Controls & Space Trajectories)
NAT · 2 Marks
Flight Mechanics & Space Dynamics • Atmospheric Flight Mechanics • Range and Endurance of Aircraft
A jet aircraft with weight W_0 = 80 kN burns 20 kN of fuel so that final weight is W_1 = 60 kN. The flight is conducted at constant airspeed V = 200 m/s and constant lift-to-drag ratio L/D = 18. If thrust specific fuel consumption is c_t = 2.0 \times 10^{-4} s^{-1}, what is the Breguet range in kilometers? (Take \ln(80/60) = \ln(4/3) \approx 0.2877, round off to nearest integer).
Answer Key:
5179
Step-by-Step Verified Solution
### Solution: Breguet range for jet: R = (V / c_t) * (L/D) * \ln(W_0/W_1) = (200 / 0.0002) * 18 * 0.2877 = 1000000 * 18 * 0.2877 = 18000000 * 0.2877 = 5178600 m ≈ 5179 km. Correct: 5179 (range 5150 to 5200).