Mechanical vs Aerospace vs Civil Engineering

The degree you choose is one of the most significant decisions you will make in your life. The choice between Mechanical, Aerospace and Civil Engineering is one often made wrong by students. You just left high school, you know you're technically oriented and like building things, but you don't have a clue which to pick. How do you actually make the decision?

Don't just rely on the university program description

Most students look at the course catalogues and decide from there. The catalogue is a very brief description of what the program aims to accomplish, the enjoyment you feel throughout your studies is much more in the fine details, from my experience. The preliminary question you should ask yourself is the scope of design you're into. Mechanical engineering focuses on designing for cost and manufacturability. Aerospace engineering focuses on the lightest, precision-based design in the most extreme conditions. Civil engineering focuses on the largest-scale designs that have to last untouched for decades. If any of the three already stood out to you, factor that into your decision.

Year one is very similar between them

Statics, thermodynamics, elasto-statics, linear-algebra, some calculus, CAD, intro to programming, materials engineering… If you sat in on a mechanical, aerospace, and civil students' first-year courses, you'd struggle to tell them apart. All of these engineering degrees build on the same foundational knowledge, and many students figure out what they're truly passionate about only at this stage. If you find out you chose the wrong degree early on, switching isn't as costly as most people fear. You might need an additional semester to fill in some gaps (soil mechanics for civil, transonic and supersonic fluid dynamics for aerospace…), but the basis is very similar. Everyone has to deal with static mechanics in their first semester. You're not messing up by jumping right into it.

Where do the 3 degrees actually split

Mechanical Engineering

Mechanical engineering is the broadest, most general degree. It dives deep into thermodynamics, fluid dynamics, structural dynamics, materials science and controls. With a mechanical engineering degree, you can work in most industries and have a wide range of jobs available. It is the most generalised engineering degree that is a one-size-fits-all option for people who want to work in a technical field, but don't have an exact field bias. With a mechanical engineering bachelor's, you can also transfer to a master's in Aerospace, although some fundamental Aerospace knowledge might need to be supplemented by you. With that being said, the two degrees do share large overlaps.

Aerospace Engineering

Aerospace Engineering covers mostly the same topics as mechanical engineering, but dives much more into aviation related topics. For fluid dynamics, compressible flows at supersonic and hypersonic speeds need to be studied due to their relevance in spacecrafts. Orbital mechanics become relevant for people interested in satellite technology. Controls engineering is a much larger focus in Aerospace due to significant applications in the aviation (auto pilot) and drone sectors (full actuation and synchronization of motors). Aerospace engineering also dives significantly deeper into mass constraints, where an exact mass budget is restricted to a much larger extent than any other degree would require. Aerospace engineering is commonly regarded as the hardest of these three degrees, due to the significant knowledge you need to have in aviation-specific sectors. This degree is the one I chose, and I don't regret it for a second. It was truly one of the best decisions I ever made in life.

Civil Engineering

Past the first year, civil engineering is quite different from the other two. Civil engineers dive significantly further into large-scale models. They focus much more on CAD design and actual physical feasibility on the geotechnical and infrastructural side. Civil engineering also dives much more into real-world issues, like transport systems, water systems, environmental engineering and construction management. Civil engineering trades off dynamic systems and tight mass balances with much larger scale projects and real world constraints. It's a really practical degree and one very worth looking into for those more structures oriented.

My own perspective

I did my bachelor's in aerospace engineering at TUM, my thesis was on dynamics and controls on drones. I am now starting a mechanical/aerospace engineering master's at ETH Zurich. I got into aerospace not being the biggest fan of anything aerospace-specific. Physics and math were my best and favourite subjects in high school, but I never was the kid who'd meticulously study plane routes or got excited for every rocket launch. I enjoyed technical subjects and I thought combustion was cool, and that's all it took for me to pick aerospace. I just thought plane engines were cool. Through my time teaching and interacting with students, I found many like-minded individuals who were concerned they chose the wrong path. Many of my classmates were exactly the 'nerds' who actually cared a lot about news in the aviation world. This doesn't mean I chose my path wrong, and if you're like me, it shouldn't drive you away from aerospace. Aerospace, broken down, is just many mechanical components working together to achieve one engineering masterpiece. If one of those components sounds somewhat interesting, give it a try. You might fall in love with thermodynamics as I did, you might find structural mass optimisation fun, or hypersonic shockwaves may just be your calling card. Just know that if you're not super into planes or rockets, there's still a home for you in aerospace. It never stopped me, so don't let it hinder you either.