Hi Dear,

Yes, you are eligible for AFCAT exam after completion of your BE/B Tech (Four Year Course) from a recognised University with minimum 60% marks or equivalent. The Air Force Common Admission Test (AFCAT) is conducted twice a year by the Indian Air Force for selection of  Officers in Flying and Ground Duties. If you are just a diploma holder then you are not eligible for AFCAT exam. However, Diploma + Engineer graduates are eligible for AFCAT.

You can visit the link below for AFCAT exam preparation:

https://competition.careers360.com/articles/afcat

Good Luck