Tempest AA48109 Oil Filter – High-Performance Filtration for Aircraft Engines

The Tempest AA48109 incorporates a magnetic secondary filtration system – an internal magnet designed to attract fine ferrous particles that are small enough to pass through the primary filter media but still capable of causing cumulative damage to engine bearing surfaces, cam lobes, and other close-tolerance components. Standard filter media captures particles down to approximately 30 microns, but very fine steel debris below that threshold can circulate freely in oil without magnetic interception. By retaining these particles in the filter housing rather than allowing them to recirculate through the engine, the magnetic system adds a meaningful layer of protection against progressive wear damage. Reviewing the filter at oil changes for ferrous material on the magnet also provides an early-warning indicator of abnormal internal engine wear before it becomes a costly problem.

The Tempest AA48109 features a patent-pending PC (Plastic/Protective) housing that encases the bypass valve, a design element that distinguishes this filter from most competitors. The purpose of this housing is to prevent the oil outlet port from becoming restricted in the unlikely event of a bypass valve component failure – without it, a failed bypass valve could physically block or partially obstruct the main oil outlet, reducing oil supply to the engine at a critical moment. By enclosing the bypass valve in a dedicated housing, Tempest ensures that even an inoperative valve does not compromise the primary oil flow path. This is a structural redundancy built into the filter design itself rather than relying solely on component reliability.

Traditional spin-on oil filters use liquid lubricants such as DC-4 compound or grease between the rubber seal and the engine filter mount pad, but these fluids can migrate out from under the seal over time due to heat cycles and operating pressure, leaving the filter effectively bonded to the mounting surface. Tempest's proprietary SPIN EZ solid lubricant adheres directly to the filter gasket and stays in place between the seal and the mount pad surface rather than extruding outward. The result is consistent lubrication at the seal interface throughout the service interval, which allows the filter to be removed cleanly with a filter wrench at the next oil change without the frustration – or risk of damage – associated with stuck legacy filters. No additional DC-4 application is required at installation, simplifying the oil change process.

The AA48109 is rated to withstand a burst pressure of 600 PSI, exceeding the ARP 1400 aerospace oil filter standard by 50%. This elevated burst strength was achieved through substantial improvements to the roll seam construction on the base of the canister – one of the structurally most stressed areas of a spin-on filter under operating pressure. For the high-performance Continental IO-520, IO-550, TSIO-520, TSIO-550, and GTSIO-520 engine families that the AA48109 is designed to serve, that additional structural margin provides meaningful assurance of filter integrity during cold starts, thermal pressure spikes, and demanding operating conditions.

The AA48109 uses a resin-impregnated, cellulosic full-pleat media configuration, offering 312 square inches of filtration surface area – among the largest available in aviation oil filters. Full-pleat construction distributes oil flow evenly across the entire media surface rather than concentrating it in localized areas, reducing the risk of premature collapse under differential pressure that can occur with fewer or shorter pleats. The resin impregnation adds structural rigidity to the media, further resisting collapse during cold-start, high-viscosity conditions when the differential pressure across the filter is at its highest. This combination of media area and structural design supports consistent filtration efficiency throughout the full service interval.

Tempest aviation oil filters – including the AA48109 – are manufactured in a dedicated aviation oil filter production facility built exclusively for that purpose, rather than in a general industrial or automotive filter plant. This total process control environment allows Tempest to maintain aviation-specific quality standards throughout every stage of production, from media fabrication and canister forming to seal assembly and final testing. Being the only aviation filter produced in a facility solely dedicated to aviation oil filter manufacturing supports the consistency, traceability, and documentation requirements that aviation maintenance standards demand.

The Tempest AA48109 and AA48108-2 share the same 3/4-16 female thread configuration but differ significantly in physical size: the AA48109 measures 6-3/16" in height compared to 4-3/8" for the AA48108-2, making the AA48109 a substantially longer filter. The AA48109 is designed for higher-displacement Continental engines – primarily the IO-520, IO-550, TSIO-520, TSIO-550, and GTSIO-520 series used in higher-performance Beechcraft, Cessna, Cirrus, and Columbia/Lancair aircraft – where greater oil capacity and media area are appropriate for the engine's output and oil volume requirements. Operators should always verify the correct filter model using the aircraft and engine maintenance manual or the Tempest application guide, as installing a filter of the wrong length can result in mounting clearance issues or incorrect oil capacity.

Yes – the AA48109 is available in six-pack packaging, making it a practical purchasing option for MROs, FBOs, flight schools, and individual operators who service multiple aircraft or prefer to maintain a supply of filters on hand between oil change intervals. Six-packs offer the cost-per-unit advantage of bulk purchasing in a more manageable quantity than full cases, with the added convenience of compact, easy-to-handle packaging. For maintenance facilities that regularly service Beechcraft Bonanza, Baron, Cirrus SR22 or SR22T, or Cessna turbocharged twin fleets, stocking the AA48109 in six-pack quantities supports efficient scheduling of oil changes without the risk of running short between supply orders.