Grimace
Well-Known Member
Whoops.. the title should have read "In-flight forces on the vertical tail". Sorry... can a mod fix that?
I feel silly for not knowing this, but I guess in a way it makes sense that I wouldn't...
Why have I never seen anything about calculating forces on the vertical tail? I'm guessing it's because most small planes build the vertical and horizontals using the same methods, just to keep things simple, and the horizontal tail carries more load, thus making the calculation of the vertical tail superfluous.
Anyway, to evaluate a potential structure, I need to at least roughly figure out what kind of loads are placed on the vertical tail. The best approach I can think of is to determine the highest bank angle at which an airplane can maintain level flight and calculate the vector which is applied to the vertical tail in that condition? And obviously this should result in a number which is lower than that for the horizontal tail, thus making the question rather moot for most light aircraft... (edit to add.. actually, at 60 degree bank, there should be more force on the vertical tail... but then is should only be a fraction of what the horizontal tail sees in a high-G pull-up maneuver, which I suppose is the more structurally-critical flight condition)
Or maybe I'm over-thinking it. Since the vertical isn't resisting the force of the wings, to get a ballpark answer, maybe I can just follow the tail volume coefficient guidelines and then calculate the max lift for a vertical tail of that given size and use that....
Is this about right? Admittedly, I haven't thought about it much, but I also haven't seen the topic covered before...
I feel silly for not knowing this, but I guess in a way it makes sense that I wouldn't...
Why have I never seen anything about calculating forces on the vertical tail? I'm guessing it's because most small planes build the vertical and horizontals using the same methods, just to keep things simple, and the horizontal tail carries more load, thus making the calculation of the vertical tail superfluous.
Anyway, to evaluate a potential structure, I need to at least roughly figure out what kind of loads are placed on the vertical tail. The best approach I can think of is to determine the highest bank angle at which an airplane can maintain level flight and calculate the vector which is applied to the vertical tail in that condition? And obviously this should result in a number which is lower than that for the horizontal tail, thus making the question rather moot for most light aircraft... (edit to add.. actually, at 60 degree bank, there should be more force on the vertical tail... but then is should only be a fraction of what the horizontal tail sees in a high-G pull-up maneuver, which I suppose is the more structurally-critical flight condition)
Or maybe I'm over-thinking it. Since the vertical isn't resisting the force of the wings, to get a ballpark answer, maybe I can just follow the tail volume coefficient guidelines and then calculate the max lift for a vertical tail of that given size and use that....
Is this about right? Admittedly, I haven't thought about it much, but I also haven't seen the topic covered before...
