Over the weekend jaydeehess and I have been playing a little with the g-load and load factors for the benefit of the gang at P4T. For the benefit of JREF members, I figured I needed to clarify some things about the math thus far. Keep in mind that I have been approaching the problem from a purely Newtonian physics aspect. My interest is in the component vectors, not fulfilling aeronautical terminology. I solved the problem for sagitta, bank angle, and centripetal force (in g's). Although I attempted to stay away from aeronautical issues, I thought it a simple matter that only one of the two vectors discussed thus far was variable and had to be determined (centripetal force) and the other vector component was fairly constant, gravitational force (g = 1). So I simply smiled as the folks at P4T and SPreston jumped up and down about how my g calculation for centripetal acceleration did not match some g-load chart they were using. Well of course it didn't! My calculation was for the variable component ONLY, centripetal force.
I don't visit the P4T or CIT forums very often and it is only by those of you who do that I am aware of the "issues". Everything I have done so far is NOT in aviation terms, and I have been very clear about that, but once again P4T took the bait and has gone on ramblings about something they have no clue about. So, since pilots are interested primarily in how much lift is required to keep the plane from falling out of the sky, I decided to do my best to in Newtonian physics terms provide a general equation for resolving that, but once again staying away from the aeronautical terms the best I could.
Well, jaydeehess decided to throw a monkey wrench at the P4T boys and define the same thing in aeronautical terms. Of course, not understanding that jaydeehess and I were talking about EXACTLY the same thing, but using different terminology, P4T invented this little game of how jaydeehess had to come along and "correct" my math. Personally, the whole thing had me on the floor laughing because all P4T was doing was once again revealing their ignorance of math.
So, pay close attention P4T.
My solution for acceleration (g-load) expressed in g's for [latex]$$ \theta >0 $$[/latex]:
[latex]$$ N = |a_L| = \sqrt{{a_x}^2 + {a_z}^2} $$[/latex]
Jaydeehess's solution for the load factor (no units, aviation definition):
[latex]$$ N = \frac{1}{cos \theta} $$[/latex]
Since,
[latex]$$ a_x = {a_L}sin{\theta} $$[/latex] and,
[latex]$$ a_z = {a_L}cos{\theta} $$[/latex] and,
[latex]$$ a_z = |{a_g}| $$[/latex] for the range of normal aviation altitude,
my equation becomes,
[latex]$$ |a_g| = \left({\sqrt{{a_x}^2 + {a_z}^2}}\right){cos{\theta}} $$[/latex] or,
[latex]$$ \frac{|{a_g}|}{cos{\theta}} = {\sqrt{{a_x}^2 + {a_z}^2}} $$[/latex]
When [latex]$$ \sum{a_z} = 0 [/latex] the equation becomes,
[latex]$$ \frac{1}{cos{\theta}} = {\sqrt{{a_x}^2 + {a_z}^2}} $$[/latex].
Oh my, jaydeehess and I are saying exactly the same thing. Thanks again for the 'correction' jaydeehess
