Do engineers really need all three calculus's?

Meh, kids these days and their Calculus 1,2,3. I was required to take a year of 5 credit calc, plus diffeq, linear, and stats. And it snowed uphill during the hurricanes too!!

All basic statics - no calc required at all. That was 5 stories worth of all concrete posts, foundation, and slabs. Nothing fancy. Simple linear loads IIRC. The prof who worked with us on this did it simply as an exercise to show it’s doable :). The concrete calculations all used basic algebra and our trusty DIN (German standards) concrete handbook tables and that was all she wrote.

I’ve used every bit of math I’ve ever learned for some purpose or other. The engineering core (Calc 1,2,3, DiffEq, LinAlg) I make use of very frequently.

After college, some engineers use their Calc a lot and other don’t. (You can’t always know ahead of time). But you need it to earn degree as well as to survive the the upper level courses. So try hard to learn what ya can!

Doubt any ABET accredited program would include less than 3 semesters of calculus plus differential equations. If you do less technical difficult work in your career, you may not use the calculus principles much (also a lot of solutions are done in computer software that is transparent to the user) but you will still be expected to be highly proficient in math related items (no civil engineer can say they are having trouble doing any work that requires Excel, etc).

Graduate school is a complete non-starter without a good grasp of calculus. The required graduate math class at JHU was very, very difficult and started a step past typical UG.

Truth is that as a general rule, you learn how to do math far before you learn why any of it matters or where it might have an application. Trust me when I say that everything in calculus, even the tedious and seemingly pointless stuff, comes in handy. You could do without it but if you do know the stuff, it is a tremendous boost for you in any line of engineering work you would do.