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SUSS SINGAPORE UNIVERSITY OF SOCIAL SCIENCES EAS309 Flight Dynamics and Control Lab Assignment Jan Semester, 2024 INSTRUCTIONS TO STUDENTS: 1. This is an Individual Assignment 2. This Assignment carries 15% of the marks toward the total Grade 3. You should prepare and submit this assignment as a formal report. 4. There are three submissions for this assignment : Submission Submission 1 Submission 2 Final 5. Submission Details: Weightage 10% 15% 75% Due Date 3rd March 2024 24th March 2024 6th April 2024 a. Submission via Canvas b. your submission should be either in .doc or .pdf format c. accompanying excel file or Matlab file to show your calculation could also be submitted. Introduction In this assignment, you are going to apply all you have learnt in EAS309 to analyse and evaluate the flight dynamic characteristics of a modern fighter aircraft. You will also attempt to design a simple flight control system to improve the aircraft flight characteristics so that it meets the flying quality requirement of a Specification (MIL- 8785). The F15 is a twin engine, highly manoeuvrable, supersonic, multi-role fighter aircraft. As the aircraft is highly manoeuvrable, the operating flight envelopes covers a wide range of AOA and AOSS. At these extremely high aircraft attitude, the aerodynamic flow over the aircraft is complex and has significant effect on the aircraft flight dynamic and stability. The variation of the key aerodynamic derivative coefficients are show in Appendix I. SUSS Aerospace System is requested to investigate the F15 flight dynamic characteristics at various AOA at both subsonic and supersonic speeds. Each student in the EAS 309 class will be assigned for one particular case, to study into the flight dynamic characteristics. You will received your assigned data package via email. The key parameters of the F15 is as follow: Mass S с b 20411.66 kg 56.485 m² 4.86 m 13.045 m Ixx Iyy Izz Ixz 38911.98 kg-m² 223845.45 kg-m² 254758.19 kg-m² -705.03 kg-m² Assignment Instruction Each student in the EAS309 will be receiving the F15 aerodynamic derivative data package. You may want to know that each data package is corresponding to different flight condition, i.e. for different Mach number and altitude, thus the data each student received will be different from each other. Based on the data package received, you shall perform the analysis, conduct the evaluation, and perform the flight control design as required in the questions listed in this assignment. You are required to work through this assignment using MATLAB. You may notice that the entire assignment span throughout the entire Semester, and you are strongly encouraged to do this assignment progressively, to avoid the last minute rush, pacing with the progress of the lectures. A recommended progressive schedule is shown below: Lab Lab #1 Lab #2 Lab #3 Lab #4 Lab #5 Lab #6 Dates 26 Jan 2024 16 Feb 2024 23 Feb 2024 8 Mar 2024 23 Mar 2024 6 Apr 2024 Activities Familiarization with MATLAB Read in parameters, static stability margin Compute all derivatives Submission #1 (3rd Mar 2024) (covering questions : 1A and 2B) Compute A and B, eigenvalue, eigenvector and modes of motion Compute aircraft response with control input Submission #2 (24 Mar 2024) (covering questions: 2C, 3B, 3C, and 4C) Simple feedback control State-space feedback, pole placement Finally, you are required to submit an individual Formal Report documenting all your findings and answers. The marks for respective and final submission are as follow : Submission #1: Only Questions underlined (10 Marks) Submission #2: Only Questions Bolded (20 Marks) Final Report: All Questions. (70 Marks) Assignment and Questions 1) Analysis the aircraft longitudinal static stability by answering the followings: (10 marks) A. Apply the appropriate theory to evaluate and present the numerical value of stability margin for your flight condition. B. From your result appraise the stability of F15, and state whether the aircraft is statically stable? 2) Appraise and evaluate all the stability derivatives (both longitudinal and lateral- direction axes) of the aircraft, and assemble the A and B matrixes (for both longitudinal and lateral-direction axes) of the aircraft (10 marks) A. Apply the theory learnt to describe the longitudinal and lateral-direction axes B. Analyse and Tabulate your answers for ALL the longitudinal and lateral- directional derivatives. C. Present your answer for Matrixes A and B for both longitudinal and Lateral-direction Equations. D. Appraise and explain the physical significance of matrix A and B? 3) Formulate and develop procedure to calculate the eigenvalue and the eigenvectors longitudinal and lateral-direction modes of the aircraft. for the (20 marks) A. Appraise and explain the physical significances of the eigenvalue and eigenvector? B. Analyse and present your answer for the eigenvalues and eigenvectors for both longitudinal and later-directional axes. C. Present the time response plot for all the aircraft Longitudinal and Lateral- Directional modes of motions D. Explain how you calculate the modes of the aircraft in Matlab. E. Apply the theory learnt to comment the lateral directional modes of the aircraft. F. Apply the theory learnt to comment on the longitudinal modes of the aircraft. G. If the aircraft was stable longitudinally, appraise the longitudinal stability characteristics : i. In terms of eigenvalues and eigenvectors ii. What are the two typical physical modes, and iii. What are the typical behaviour of these two modes. 4) Formulate and develop procedure to compute and plot the aircraft lateral- directional response when the aircraft is subjected to an impulse aileron input (10 marks) A. Apply theory learnt to explain the difference between impulse and step inputs? B. Appraise and explain the formulation you used in Matlab to compute the aircraft responses. C. Analyse and present the time response of the aircraft when subject to impulse aileron inputs D. Apprise and comment on these time response curves. i. Do you see an isolated mode or all the modes ii. Do you see any difference "when time is small" and "when time is long" 5) Formulate and develop a simple pitch feedback classical control is to improve the damping ratio of Phugoid mode. (20 marks) A. Appraise and explain the choice you have for the transfer function in your Matlab formulation B. Analyse and present the Root-Locus Plot C. Apply theory learnt, comment on how the damping ratio is changed with different gain, using the Root-locus plot computed. D. Appraise the meaning of "gain" in the question above.