There are many CAD programs, almost all of them require a large investment in time and ofter money.
I just discovered shapr3d. It looks awsome. I don’t say this lightly. But it looks to me like this is going to be a gamechanger.
I managed to create this cowling as a test-object.
Is there a downside: yup, it needs an ipad. So far I’m lucky enough to be able to use the one provided by my boss.