An Aeronautical Engineer can get opportunities in Space Research Centres, Aeronautical Development Establishments, Aeronautical Laboratories. Aircraft Manufacturing companies, Airlines, Defence Research and Development Organisation, Defence services, Department of Civil Aviation, Flying clubs, Govt. owned Air services and private airlines. And all these profiles do have software wings and so within these departments, you can work with your proficiency as a CSE Graduate. But to work as in and as an Aeronautical Engineer, with only a CSE background, it is tad difficult. You may have to do your M.Tech in relevant field.