F1 car design in Catia V5 ii

Define ALL BODYWORK TOP PROFILE as "in work object" so that the new line we create appears under this geometric set. Now I'm ready for my first 3d curve. The points on this curve should be the ends of the lines we earlier created.

Now double click on the line just created. Right click on all the points that are on the ends of straight lines and impose tangency. Impose curvature as well.

Before I go further, I'm going to need some other DIMENSIONS. Add a geometrical set under DIMENSIONS "NOSE & MONOCOQUE MATING LINE" Switch back to the Generative Shape Design workbench for this. Create a point by coordinates at X=-755. Constrain it to plane yz. Put a couple of infinate lines through it.

This next DIMENSION is one of the keys to the project. It's hyper important for this model. Insert a geometric set SIDEPOD MATING WITH MONOCOQUE. This line will be used a ton later. Change to a side view, add a point, constrain it and put a couple of infinate lines through it. The lines should be at the frontmost point of the sidepods.

Actually, now that I think of it, it would be useful if the lines and points in Dimensions looked different. Right click on DIMENSIONS geometric set, select properties, makes some changes.

Ok, moving on. As can be seen below, we need to add some more points on this 3d curve, as it doesn't match up with our drawing.

Define ALL BODYWORK TOP PROFILE - POINTS as the in work object. Hide the 3d curve under ALL BODYWORK TOP PROFILE, to make it easier to see our 2d sketch or drawing of the car. Add a point on NOSE & MONOCOQUE MATING LINE and change the distance on the line until it lies on the 2d sketch

Do the same using SIDEPOD MATING WITH MONOCOQUE.

Unhide the 3d curve under ALL BODYWORK TOP PROFILE, double click it to edit, click the circled button to insert a point, click on the 3d curve in between the points where you want to add a point, and constrain you new point on the points we just created.

We're getting closer to matching the 2d sketch or drawing. Add some more points on the 2d sketch or drawing and attach the 3d curve to them. This is going to take time and some trial and error. It's worth noting that it's really important that all the points are Z=0. This line has to lie on the Z plane.

Go through and ensure that all the tangencies on this 3d curve are set to norm = 1mm for now

Now I'm going to add a tangency and curvature restraint on the 3d line at the point we set on SIDEPOD MATING WITH MONOCOQUE to smooth everything out so that it matches our 2d sketch or drawing.

Looks good up front. How about at the back? As it is now, our 3d curve doesn't match up to our sketch.

Edit the norm of the tangency on the 3d curve so that it matches the sketch.

Hide ALL BODYWORK TOP PROFILE - POINTS, and we are left with a nice 3d curve.

I you can achieve similar results using a different method, go for it. I think this could be reproduced using a spline in the sketcher bench. I find this method much easier because I'm more familiar with using programs like Corel Draw to create vector graphic curves. I'm highlighting this method in detail because it took forever for me to learn, and I'll be using it extensively moving forward.