▲ 6 r/Pilot
Is 20/20 -2 in one eye still ok for getting a first class medical?
I know you need 20/20 distant in each eye separatly. Hoping that this is good enough.
u/VVsleekman — 13 days ago
▲ 3 r/Pilot
Question on center of lift, center of pressure, and aerodynamic center.
Howdy y'all, I am working on completing PPL ground school and had a question relating to aircraft controllability. For reference, i am using free pilot training on youtube and trying to delve more in depth where i can.
Initially, i was learning about how aircraft controllability is impacted by changes in angle of attack and speed through the center of lift and center of pressure. I was curious as to why center of lift does not change positions, but center of pressure does and what their differences were. When looking online i seemed to find contradictory statements on what each were, and also kept getting results for aerodynamic center when searching up center of lift. Despite this, some sources seem to use them interchangeably, while others will say they are different.
As i understand, center of lift is the point on the airfoil where lift is concentrated (i assume this is the same as the average), and center of pressure is the point on the the wing where the total aerodynamic force be considered to act. Would anyone be able to explain the differences in all of them, and how each is affected by change in angle of attack? Thanks!
u/VVsleekman — 24 days ago
▲ 5 r/Pilot
Can an aircraft be dynamically stable while not having positive static stability?
Howdy! I'm working on completing PPL ground school, and was reviewing some of my notes on aircraft stability. I understand (or at least I think i do) the basics behind each of the types of stability. I think my confusion comes from the usage of "waves" and oscillations as examples in each scenario of stability. Static stability is the initial tendency of the aircraft after its equilibrium has been disturbed, and dynamic is the long term tendency.
I am wondering for example, if i am in an aircraft that pitches up due to turbulence, and the airplane is not positivly statically stable and does not initially pitch back down, how can it have any form of dynamic stability? If the plane has neutral or negative static stability, it shouldn't oscillate at all as shown in examples of dynamic stability.
I'm probably missing something super simple so any help or explanation would be super appreciated! Thanks!
u/VVsleekman — 1 month ago