So i am trying to create a plane using google sketchup, and having no prior CAD experience or no experience at all... I looked on youtube, and i made a wing!

so right now i am trying to build the body to the plane, buuut, i dont know how i am supposed to make the nose of the plane, i make a 2-d outline of it.. is what i have drawn, but i want it to be 3-d (obviously) and i cant figure out how to change that flat edge to be a round edge and still keep a rounded nose of the plane..

I have limited experience so i am sorry if this is in the wrong spot or not..

The reason i am making this?
I want to use my google sketch up as a guide to create a mold.. I want to make a mold of the parts and create a plane for my NanoComposites class... We are vacuum molding so I need to create a mold capable of creating a plane..

I will check back in around 6 hours as i am going to work... Thanks for the help (hopefully :/)