Diploma

Each state conducts its own entrance exam for diploma engineering.
The best colleges you find in Uttarakhand & Uttar Pradesh. Because their fee structure isn't high and in government colleges, they also provide good placements.

Dear Chandan,
You have to appear in LEET exam conducted by each state every year.
For example, in Uttarakhand, exam's name is UKSEE & same in Uttar Pradesh. Also, there is one exam & in Delhi, Indraprastha University conduct exam. Moreover, some university also conduct own exam.

You can do any diploma after BBA.

Majority of universities allows polytechnic diploma holders to seek admission in graduation degrees such as BBA.

You have following options to become Aeronautical Engineer:
(a) Lateral entry B.Tech in Aeronautical Engineering. You may evaluate Manipal Institute of Technology for same.
(b) You can join Aeronautical Society of India (AeSI). The AeSI is a professional body, devoted to advancement of aeronautical s

Dear Himanshu,
Yes, if you did Diploma engineering course then you can apply for government jobs where mechanical engineers are required.

You can seek lateral entry admission in aeronautical engineering 2nd year after Diploma in mechanical engineering. You may evaluate Manipal Institute of Technology for the same.

Yes, you will get the admission but you will have to qualify LEET entrance exam or colleges’ entrance exam.