LIDO
 

Good afternoon, I have been trying to find a definition for the turbulence index on LIDO flightplans. On our flightplan there is the wind, FL, and a turbulence number. Does anyone know where I can find a definition of that turbulence factor? I have used the search function here but got no results.

hey,
Don't really know where to get the definition of turb no. but.... if I'm not mistaken.. it refers to the vertical wind speed in feet per minute.. i.e 1=100, 2=200,3=bumpy, and it gets worse from there.
evo.

Thanks evo. Our Part A specifys that 5 is moderate turbulence but thats all.

I remember that in the early days of computerized flight plans, the turbulence index represented "knots per thousand feet", e.g. index 3 would be a change of 3 knots of wind velocity per thousand feet altitude change.
I got this info from the software developer at that time and believed his word for it, but can't find an official document supporting it. For all I know, it could be meters per seconds instead of knots.

FWIW our Ops manual says something like:

'Wind shear ratio based on an algorithm that compares wind speed and direction 2000 feet above and below the cruise altitude.'

I also thought that it was wind change in knots/100ft. My experience of LIDO though leads to to the conclusion that the figures are almost useless. Had white caps on my coffee with W/S 0 and been smooth as a babies bottom with W/S forecast of 10!

turbulence index on LIDO flightplans
 

They have different calculation methods in place. Which one is used on your flight plan actually depends on which method was requested from your company.