Donaldson Air Filters Improve Horsepower on Beechcraft Aircraft

MINNEAPOLIS, MN – January 19, 2010 – Donaldson Company (NYSE:DCI), a leading, worldwide manufacturer of filtration systems and parts, is pleased to announce FAA-PMA approval for several dry media inlet air filters for Bonanza and Debonair aircraft. The new general aviation engine air filters take advantage of the latest filtration technologies and provide customers with advanced dry synthetic alternatives to traditional oiled or foam filters.

Donaldson developed oiled filter media in the 1930s. Since then, Donaldson developed upgraded, dry media barrier filters to increase filter life and provide greater engine protection for general aviation platforms. Airflow tests show Donaldson's general aviation filters allow for maximum engine horsepower compared to oiled or gauze filter elements. Manufactured using pleated dry synthetic media,

Donaldson's filters are optimized to offer low restriction and superior engine protection. The Donaldson engine air filters have significantly longer life and require less maintenance than foam or oiled filters. They last 500 flight hours, three years of service or five cleanings - whichever comes first - and require no messy oils or cleaning agents.

Benefits of filters made with dry synthetic media over oiled and foam inlet filters:

• Increased engine protection

• Higher efficiency, longer life - 500 flight hours, three years of service or five cleanings - whichever comes first

• Exceptional wet weather performance

• No messy, sticky oils

• No oil servicing procedure, replacement or movable parts

• Only filters to meet FAR 23.853 - flammability requirement

For more information on Donaldson General Aviation products, visit or contact the company at 866-323-0394 for more information.

About Donaldson's Aerospace & Defense Group

Donaldson's Aerospace & Defense Group is a leading worldwide provider of filtration systems for the aerospace and defense industry. Our filtration solutions protect fixed wing aircraft, rotorcraft, military ground vehicles, electronic equipment, space vehicles, missiles, military shipboard systems, and amphibious vehicles. We are committed to advancing filtration technology, providing quality products and prompt customer service. Our group serves customers from sales, engineering, and manufacturing locations around the world.

About Donaldson Company

Donaldson is a leading worldwide provider of filtration systems that improve people's lives, enhance our customers' equipment performance, and protect our environment. We are a technology-driven company committed to satisfying our customers' needs for filtration solutions through innovative research and development, application expertise, and global presence. Our employees contribute to the company's success by supporting our customers at our more than 100 sales, manufacturing, and distribution locations around the world.