RalphInCA
Cleared for Takeoff
Where can I find "official" definitions of turbulance? I.E. What light chop, moderate chop, severe turbulance means?
Never mind. I found it. Google is my friend. http://maps.avnwx.com/help/turb_desc.html
Where can I find "official" definitions of turbulance? I.E. What light chop, moderate chop, severe turbulance means?
Turbulence: In fluid dynamics, turbulence or turbulent flow is a flow regime characterized by chaotic property changes. This includes low momentum diffusion (bumps), high momentum convection (chop), and rapid variation of pressure and velocity in space and time (shear).
According to my CFI
light turbulence = most passengers will think it is medium to heavy
mod turbulence = in small planes you will be hitting your head on the roof of the plane
heavy turbulence = you really do not want to do this in a small plane
sever turbulence = you do not want to do this in any plane
Umm, that's true, but it has nothing to do with what "light chop" is.
The AIM reference is the correct one. There is an analogous Navy chart, but it isn't any different.
The OP is asking a good question. Many light aircraft pilots drastically overreport turbulence.
I heard a report of "severe" over Half Moon Bay once, from a 172, to NorCal. NorCal asked if they needed clearance (it was under Class B). Severe turbulence means momentary loss of control, and the appropriate action is to get the F out of there so it doesn't turn into extreme.
I experienced moderate on that flight. I think the other pilot did, too, though there is no way to know.