"Columbo" is a fun and challenging exercise in which the student has to "play detective" to figure out how to create the part with what appears to be an insufficient number of dimensions. 

This exercise is designed to force the student to "think", and to use CATIA to solve the problem.

After the student creates the wireframe using intersecting planes, surf1 is used to surface the part.  The "blend surface" technique used on the Angled Slot Block is used to create surfaces in areas where surf1 + corner cannot be used.