FAA: Water-Based Coolants Can’t Protect Rotax Aircraft Engines Past 120 Degrees Centigrade

Evans Cooling Systems found itself the beneficiary of a recently revised FAA Special Airworthiness Information Bulletin (SAIB) recommending waterless coolants for Bombardier-Rotax (Rotax) 912 A, 912 F, 912 S, and 914 F series reciprocating engines.


SUFFIELD, Conn., – October 14, 2009 – Evans Cooling Systems, Inc., (www.evanscooling.com) patent holder and manufacturer of the only commercial waterless engine coolants, found itself the beneficiary of a recently revised FAA Special Airworthiness Information Bulletin (SAIB) recommending waterless coolants for Bombardier-Rotax (Rotax) 912 A, 912 F, 912 S, and 914 F series reciprocating engines used in aircraft. The Rotax engines are popular in small aircraft and in UAVs, such as the Predator.

The revised SAIB was issued after the European Aviation Safety Agency (EASA) advised the FAA of possible coolant losses and engine overheating on Rotax 912 and 914 series engines. Based on these findings, EASA published AD 2007-0155, dated May 29, 2007, that requires use of a waterless-type coolant if the engine coolant exit temperature will exceed 120 centigrade (C).

The SAIB states that “If you use a conventional ethylene-glycol/water coolant, and engine coolant exit temperatures exceed 120°C, loss of coolant, engine overheating, knocking, and engine damage can occur, which could result in an in-flight shutdown.”

Evans waterless coolant has a boiling point above 180 C at atmospheric pressure, providing a wide separation between its boiling point and the operating temperature of the system.

“Evans waterless coolants protect engine metals at coolant temperatures that are well beyond the failure temperatures of water-based coolants by preventing the formation of vapor that insulates hot metal from liquid coolant,” stated Mike Tourville, Director of Marketing at Evans.

Evans waterless coolants offer safe operation at elevated temperatures for any internal combustion engine, making possible fuel-saving strategies that include reduced fan-on time. Cooling systems using Evans waterless coolants operate at lower pressure because they do not contain a vapor component. Evans waterless coolant eliminates pump cavitation and cylinder liner cavitation in heavy duty engines.

For more information on Evans waterless coolants, visit the Evans website at www.evanscooling.com, or call +1.860.668.1114.

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