- Question 3 A The Transfer Function For The Unaugmented F 4c Phantom Aircraft At 35000ft At Mach 1 2 Is Given By E S 1 (46.53 KiB) Viewed 24 times
- Question 3 A The Transfer Function For The Unaugmented F 4c Phantom Aircraft At 35000ft At Mach 1 2 Is Given By E S 2 (44.69 KiB) Viewed 24 times
I sincerely require help to understand how to go about handling
this kinds of question.
Please kindly do not copy and paste from previous questions
posted previously.
A step by step approach and neat hand writing will be
appreciated.
Thank you once again.
Question 3 (a) The transfer function for the unaugmented F-4C Phantom aircraft at 35000ft at Mach 1.2 is given by : e(s) -20.6(5 +0.013)(8 +0.62) rad/rad (52 +0.017s +0.002)(52 + 1.74s + 29.49) n(s) (i) Develop the characteristics equation and solve for the frequency and damping factor of the two stability modes. (4 marks) Name and list the characteristics of both Stability Modes. (4 marks) (iii) When an impulse elevator input is applied, what will be the steady state value of pitch angle? (5 marks) To improve the damping ratio of the higher frequency mode to 0.7071, a control algorithm is proposed using elevator as feedback as shown in Figure Q3(b-1): ( (b) Demand + 8,5) Σ Elevator angle n(s) Aircraft dynamics G(s) Response 05) Feedback gain ko Figure 03(b-1)
The root locus plot of the augmented characteristics is as follows: 6 4 Ko = 0.643 ка = 1.06 2 Ko = 1.49 KO = 1.87 Imaginary Axis (seconds) o -2 4 -6 -6 -4 -2 0 2 Real Axis (seconds) Figure 03(5-2): Root Locus Plot of KG (i) Apply Figure Q3(b-2) to identify the Root where the damping ratio is approximately 0.7071. What is the complex number of the Root? (4 marks) (ii) Hence or otherwise, appraise the corresponding gain Ko. (2 marks) (iii) Based on this gain Ke, formulate the augmented characteristic equation in polynomial. (6 marks)