705pilot
I see You operate in Canada, possibly?
Time to read up on basic met stuff , Eh?
Have you ever had fan ice at say 9 or 5c pluss in icing condition?
I have not, but I have had at plus two in FZ fog , drizzle or rain.
And that brings me inside freezing conditions defined by visible moisture and 3c or less.
Last time I saw fan ice was the other week DH out of Oslo Gardermoen with minus 12 and a good 3 to 6 mm of solid ice on the back of the CFM56.
Took 10 minutes of hot air to thaw AND dry it.
2 chaps quite happy to do the job as they snuggled inside the engines.
This was picked up in the inversion that often forms there , on the approach.
Nothing on the way out as it was in my estimate 2km in -FZFG overcast 300`
As I recall it we did 40% , then 70% : No vib, all normal, TOGA.
There is some extreme instances at OSL ( Oslo) were they damaged some 8 or 10 engines over a 24 hr period due to fan ice. There is some reports out there.
Lastly, how do You use 120kg extra in 30sec at 70% N1, Dude , that is 13200kg FF/ hr.
The extra fuel used is marginal and the least of your concerns the day it counts.
No disrespect , but dig in the manual and pester your trainers!