I see a lot of confusion in this terminology in the pizza industry. It seems that we were all taught that if an oven employs air movement to improve its baking characteristics it’s a convection oven. To some extent this is true, but there is a great distinction between air movement as it pertains to air impingement baking and air movement as it pertains to convection baking. This is much like the distinction between a ship and a boat. They’re both “boats” in a sense; but, in usage, there is a considerable difference.
Convection ovens have forced air movement to improve their baking properties, but this air movement is pretty tame as compared to that used by air impingement ovens. Typically, one might see airflows of 400 to 600 linear feet per minute in a convection oven. When we step up to an air impingement oven, those airflow rates jump up to a whopping 1,500 linear feet per minute. Additionally, the airflow pattern in a convection oven is not highly focused on the product being baked, where as the airflow in an air impingement oven is highly focused right onto the product, allowing the heat to better penetrate the product and resulting in a significant reduction of overall bake time. Also, since the air is so highly focused in the air impingement ovens, it’s possible to manipulate the airflow characteristics in very specific parts of the baking chamber by making changes to the “finger inserts” through which the air flows to achieve very specific baking conditions as the product passes through the baking chamber.