dgriletz

Is there a guide to all the variables and how to use the simulator effectively, or can someone help explain it? I've tried researching what I can on my own but am still confused about much of this. From what I understand..please correct me if I am mistaken on anything [static Analysis Tab] cl - How much lift cd - How much drag cm - Pitching force up or down. You want this to be negative so the plan naturally noses down. ld - lift/drag (Best way to use this? what does it tell you exactly?) [DOTA+Stability Derivatives Tab] What does DOTA stand for? Density - Assume this is atmospheric density, and relates to your altitude. Aircraft Properties Winged Area - Wing surface area Scaled Chord - Scaled? Wing distance from front to back Scaled Span - Distance from root of wing to tips? Moments of Inertia Is this the relative torque required to rotate the craft in each plane? i.e, high lxx means it takes more force to roll? Products of Inertia confused how/why this one works. u - "u (lower case) is used for speed of the oncoming flow along the X body axis" -wikipedia Longitudinal Derivatives Down Velocity I think this is..'If your craft is level, and dropped straight down.. what happens?' Zw - should not accelerate faster the more it falls. Obviously drag should slow it. Xw - should tend to nose down and accelerate in x direction Mw - ^nose should drop^ Forward Velocity What happens due to your airspeed starting from straight and level Zu - should gradually loose altitude Xu - should gradually slow down (from drag) Mu - I don't get this one, or why the sign is not important Pitch Rate Derivatives Level craft sitting still. It is given a pitch up motion. What else happens as a result? Zq - Because of the pitching up, does it gain or loose altitude Xq - Does it gain or loose speed Mq - does it pitch up more and more, or does it gradually slow. Should slow. Pitch Control Derivatives When you pitch up, what else happens. What is that symbol? Z?e - Not totally sure on these. Why should this be negative? X?e - Why unimportant? M?e - It you apply pitch up control, obviously you should pitch up more. Makes sense. Lateral Derivatives Sideslip Derivatives If your craft is yaw angled left or right.. Hopefully I've made sense of these.. Seems these three should happen mostly as a result of the vertical stabilizer catching the airflow. Yb - Wind is coming from the right, plane should translate left. Lb - Wind is coming from the right, plane should roll left. Nb - Wind is coming from the right, plane should yaw right. Roll rate Derivatives If your plane rolls right.. Yp - If you roll right, plane should translate left. I assume this is because of vertical stabilizer pushing against the air, moving the plane left. Lp - If your plane is rolling right, it should eventually decelerate rolling right on its own? Np - Plane rolling right, does yaw right rate increase or decrease I assume that for most planes this will be positive due to vertical stabilizer being top/rear? Why is this value listed as unimportant? Yaw Rate Derivatives As plane has yaw right motion.. These values seem to be because of the rear fins catching the wind. Yr - Should accelerate in y direction (translate right) Lr - Should roll right. Nr - Left to it's own devices, the yaw right motion should slow [sIMULATION] Please help me understand how to use this. init u - Initial forward velocity? in m/s? mach? init w - Initial vertical velocity? init q - Initial pitch up rate? What values/units? init 0 - Initial aoa, or intial pitch? In degrees? End time - How many seconds to run the sim? dT - No clue! Thank you for any assistance.