GATE_AE_2027_MOCK_01_Q23GATE 2027 Aerospace Engineering All-India Master Mock 01 (Foundation & Standard Core Calibration)MCQ · 1 Mark
Flight Mechanics & Space Dynamics • Static Stability & Control • Static Margin & Stick-Fixed/Free Stability
Stick-fixed static margin $K_n$ of an aircraft is expressed as $K_n = -\frac{dC_m/dC_L}{1}$. For an inherently longitudinally stable aircraft, the sign of $\frac{dC_m}{dC_L}$ must be:
(A) Negative
(B) Positive
(C) Zero
(D) Indeterminate
Answer Key:
A
Step-by-Step Verified Solution
### Solution: Since $K_n = -\frac{dC_m}{dC_L} > 0$ for stability, the slope $\frac{dC_m}{dC_L}$ must be strictly negative. Correct: A.