Hello,

You have not mentioned your category.Assuming that you need belong to general category in 2019 the JEE Advanced opening rank and closing rank for general category for AE were 58.60% and 34.14% respectively.So, yes with 60% or above may give you chances of getting seat in IIST in Aerospace Engineering.But cut off may increase or decrease depending on difficulty of exam, seats available etc.

And JEE Main cut off is yet to be announced.Candidates must qualify in order to appear in JEE Advanced.Scoring 85 percentile or above may give you decent chances of qualifying JEE Main so with 90 percentile or above you may qualify JEE Main.