What would you ask if you needed piping system for a power plant next to a river

Name a time you had to explain something complicated in a simple way? Explain a time when a project went wrong? Technical question was a very very basic fluid-structure interaction style question. They give an example of a structure that they want you to improve the design of or check if it's good enough. The technical question just required remembering some basic structures concept like stress distribution on a beam rod. If you cant remember they help you out and dont expect you to remember the equations but you should be familiar with basic concepts taught in first year engineering. Bending moment equation/diagram and the stress equation for a beam. Some basic fluid mechanics to do with pressure (not difficult at all). They just want to see you are aware of basic fundamentals and that you can create/suggest a creative solution. This part I did well in. Getting the technical question right is only 40% of the job. you must show enthusiasm and excitement when they ask you the competency question and hobbies. Before this point i realised this place wasnt for me and so it was hard for me to do this. You need to have a good conversation and find common ground. The interviewers are really nice people! Overall very simple but after the tour i felt it wasnt for me as i was more into CFD and fluid mechanics and was told that i would work on projects that might not be fluids related. Also, only 10-20% of projects are aerospace/aeronautics related, so I kinda gave off 'not bothered' energy as they felt it might not be the best place for me and I agree.