Selecting Your Turbine Engine Oil

Turbine engine oils, sometimes referred to as jet oils, turbo oils or abbreviated to TEOs, are speciality lubricants designed to support the operation of turbine engines. First developed during the 1940’s, turbine engines can now be seen on almost all commercial aircraft currently in operation. While aviation is the main market place for these oils, there are other applications, especially in the power industry, where turbine engines are used.

Unlike piston engines, that convert an up and down movement from a piston into motion, turbine engines combine compressed air with the chemical reaction from the fuel within the engine to drive fan blades. This means that turbine engines reach much higher temperatures, and this has driven innovation in mineral TEOs, and subsequently synthetic TEOs.

Specifications and Approvals for Turbine Engine Oils

While HTS and HPC oils are capable of working under higher temperatures, when working with engines that do not reach these temperature limits some users may prefer an STD or SPC grade oil due to better seal elastomer compatibility.

 It is important to note that receiving an SAE or MIL qualification does not complete the approval process, and separate approval should be sought from the engine manufacturer, through either engine development projects or a complete flight evaluation.

Turbine Engine Oil Composition and Additives

Turbine engine oil is a highly engineered lubricant composed of two essential components: base oils and additives. The base oils — either highly refined mineral oils or synthetic oils — are selected for their ability to withstand the extreme temperatures and operating conditions found in turbine engines.

The additive packages play a critical role in enhancing oil performance. These additives provide thermal and oxidative stability, protect engine components from corrosion, and help reduce the buildup of harmful carbon deposits. They also contribute to the oil’s load-carrying capacity and seal compatibility.

The combination of base oil and additive chemistry largely defines the specific turbine engine oil types available on the market today. For example, synthetic oils are typically used in high-performance aircraft and gas turbines due to their superior stability and lifespan, while mineral-based oils are often preferred for equipment preservation and storage.

Frequently Asked Questions About Turbine Engine Oil

Is turbine oil the same as gear oil?

A: No, turbine oil and gear oil are designed for different mechanical systems. While both provide lubrication, turbine engine oil is formulated to handle the high temperatures and speeds of turbine engines, whereas gear oil is typically used in systems with heavy loads and lower operating temperatures.

Are piston and turbine engine oils interchangeable?

A: Although some aviation oils may be compatible for limited operational needs, turbine engine oil is not interchangeable with piston engine oil. They are formulated differently to meet the unique performance demands and temperature ranges of their respective engine types.

What are the main types of turbine engine oil?

A: The two primary turbine engine oil types are synthetic and mineral-based. Synthetic oils offer better high-temperature stability and longer service life, while mineral oils are often used for preservation or in older engine models.

How often should turbine engine oil be changed?

A: Oil change intervals for turbine engines can vary by engine model and usage but are often based on operating hours or oil condition monitoring. Some synthetic turbine engine oils can last up to 25,000 hours with proper system checks in place.