I was assigned with a task, where I'm supposed to make a model of a pressure vessel cover (pic and file included). Firstly I had an issue with how to insert 6 planes with angular distance of 60 degrees. After managing to create 1 plane, and making a sketch, the Rib feature failed to create a rib. Also, I'm completely new to modeling, and this is my 3rd assignment...

Q: What am I missing here ? Any other ways to create 6 ribs in 1 go ?