LIDO

[CliqClaq]

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.

[evo8mr]

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.

[CliqClaq]

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

[Lemper]

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.

[mbcxharm]

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.'

[Fly3]

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!

[Mörfi]

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.