Building The PW-R2800 Step 1

This drawing is for an illustration of Pappy Boyington's Corsair.
I will explain now how I drew the engine, a PW-R2800.
As you can see here, the cowling cylinder shape can be inserted in a polygon shape that follows the angles of the perspective. Copying these angles you can make the same geometrical cage in another sheet and make it bigger to include more detail. The rhomboid form that surrounds the circle that in the aircraft is the hole of the engine can be used to fit the beginning and end of the crank case of the engine as I will show in step 2 .