This is the second video in a series summarizing my notes for the design, analysis, fabrication, and testing of flying wing style aircraft from an engineer's approach. This video builds upon Part 1, so please go watch that video and understand its contents before watching this one. This video covers the derivation and explanation of each of the 18 important stability derivatives, and explains why this is important and not just meaningless math. Towards the end, there is a practical example of an aircraft analysis, investigating the stability derivatives before and after a minor design change. To wrap things up, I summarize several common methods to determine the stability characteristics of your aircraft design before your first flight test.
Again, if you catch something that is incorrect here, please let me know! I filtered through the final cut as best as I could, but I'm here to learn, so I'm all ears!
Incredible sources for stability:
https://aircraftflightmechanics.com/NotesIntroduction.html
https://courses.cit.cornell.edu/mae5070/DynamicEquations.pdf
https://courses.cit.cornell.edu/mae5070/Caughey_2011_04.pdf
Perkins, C. D., & Hage, R. E. (1966). Airplane Performance, Stability and Control. John Wiley & Sons.
McCormick, B. W. (Year). Aerodynamics, Aeronautics, and Flight Mechanics. John Wiley & Sons.
https://eaglepubs.erau.edu/introductiontoaerospaceflightvehicles/chapter/aircraft-stability-control/
https://www.micropilot.com/pdf/stability-derivatives.pdf
https://mail.tku.edu.tw/095980/8_Stability%20and%20Control.pdf
0:00 Intro
0:39 Why should I watch this??
02:40 Common Aero Definitions
03:43 Equations of motion
05:33 Forces + Moments
07:23 Common Stability Derivatives
07:51 Deriving the Stability Derivatives
11:53 Normal Force / Pitching Moment
13:23 Side Force / Rolling Moment
14:54 Yawing Moment
16:33 Derivatives: Speed
17:25 Derivatives: Pitching Moment
18:33 Derivatives: Rolling Moment
21:17 Derivatives: Yawing Moment
22:49 Derivatives: Side Force
24:30 Rules of Thumb
25:09 Design Analysis Exercise
29:49 Stability Analysis Methods