AS9120B, ISO 9001:2015, and FAA AC 0056B ACCREDITED

Airplane Cowling Function and Uses

Automobile, aircraft, motorcycle, and boat motors all have something in common, their engines require protection from harsh external elements, as well as overheating. Aircraft, in particular, feature a removable metal cowl which contains the engine, and occasionally, some of the nacelle. Primarily, engine cowling streamlines the airflow outside and inside an aircraft to improve cooling. Past aircraft relied solely on airflow for cooling, but the extremely powerful engines of today require additional cooling measures to prevent engine malfunction. Cowling completes the upper section of the baffles which helps airflow move around the cylinders to keep them cool.

Aircraft engines are often housed in a structure referred to as a cowling which is a protective covering. Often found on automobile engines, in addition to airplane engines, these coverings protect the apparatuses they are a part of, especially from physical damage. In addition, airplane cowlings are effective at reducing drag because of their streamlined design; they consist of two cold air inlets and a bigger warm air outlet below. Engines which use water for cooling feature an additional inlet to give the coolant radiator space. Cowlings also help keep aircraft engines from overheating by facilitating cooling; they transfer heat away from the engines so they cannot overheat. Moreover, larger cowlings are often intended to cover and protect other parts of the body of the aircraft.

An airplane cowl features cowl flaps which are small doors built into the bottom of the cowling that make greater cylinder cooling possible during takeoff and climb. However, aircraft without cowl flaps likely have efficient enough cooling systems to do without them. Typically, air moves through the engine cowl while it collects the heat produced as a result of the combustion process, and this air exits through openings underneath the cowling. Bigger engines generate much more heat than smaller sized ones, so they necessitate tighter cowling to lessen drag. When the cowl flaps are opened up, they increase the amount of cool air received because the cowling outlet gets wider to accommodate airflow.

The cowlings used today utilize ram air pressure so that only a very small quantity of air is working to maintain streamlined flight and minimize drag. On the inside of the cowling, cooling happens either up-flow or down-flow, with most engines using the down-flow method in which air enters the cowling above the engine and moves downward to leave the cowling underneath the aircraft. Though, pusher-type engines would use up-flow cowling. There are many parts of the engine cooling and cowling system, including the top and bottom cowling, air inlet area where cool air enters, a pressure chamber, baffles, expansion chambers, and an outlet area where the expanded warm air leaves the aircraft. 

Those in the market for high quality aircraft cowling, bearings, connectors, fasteners, and other aircraft parts should look no further than Integrated AOG. As an AS9120B, ISO 9001:2015, and FAA AC 00-56B accredited parts distributor, you can trust the caliber of our offerings. A leading supplier for Airbus Cessna and Bombardier, we have more than two billion new, used, obsolete, and hard-to-find parts available for your immediate purchase, many of which are subject to rigorous quality assurance measures. Once you place an order with us, our team works diligently to get your parts to you as quickly as possible. Take your time to fill out one of our online RFQ forms with as much information about your needs as possible. One of our dedicated account managers will get you a quote within 15 minutes of your submission.



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