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A new benchmark - for high performance turbine engine oils.

Image of a plane

For many years the world’s finest aviation scientists struggled with a problem that seemed almost impossible to solve.

The challenge was to produce a High Performance Capability (HPC) oil that could deliver the optimum balance between low coking and elastomer integrity.

In the past, no HPC oil had managed to achieve this, because improving the oil’s low coking properties always meant that engine elastomer seals deteriorated faster.

It meant that some of the benefits of using a higher performing oil were instantly neutralised, and airline operators still faced the same problems of aircraft downtime and reduced profitability.

No oil formulation, it seemed, could capture the ideal balance - until now...enter AeroShell Ascender.

What makes AeroShell Ascender so different?

AeroShell Ascender takes turbine engine oils to a completely new dimension. It has been specifically developed to provide the optimum balance between low coking and elastomer compatibility. It’s also designed to cope comfortably with the new generation of jet engines – where conditions are hotter and maintenance intervals are longer.

Back to basics - to meet demanding specifications

In formulating AeroShell Ascender, our scientists went right back to basics, effectively reinventing the oil’s DNA. Over ten years of exhaustive research and development, we listened to customers, OEMs and engine specialists. We tested our prototype oil more rigorously than any other AeroShell product in Shell Aviation’s history, with the goal of delivering a formulation with the optimum balance.

The results

Image of the coke deposit on bearing housings

Coke deposit comparison tests on bearing housings

AeroShell Ascender became the first new formulation to fly through the new civil turbine oil specification SAE AS5780A approval process, setting a new benchmark for high performance turbine oils. For us, it’s a significant achievement.

For you, it means less coking, more protection, greater seal integrity.

Examples of the differences between the performance of Standard and High Performance Capability oils according to SAE AS5780A
Oxidation & Corrosion Stability, 72 hours @ 204 °C Standard HPC
Viscosity Change, %  -5 to +25 0 to +22.5
TAN Change, mg KOH/g 3.0 max 2.0 max
Sediment, mg/100 mL 50 max 25 max

Shell Aviation - Most tested lubricant

AeroShell Ascender has been in development for a decade. During that time, we’ve conducted extensive discussions with customers and engine manufacturers to get to the heart of their needs.

Good enough is not enough

Image of ELASTOMER COMPATIBILITY TEST

Over the last ten years, AeroShell Ascender has been subjected to more tests than any other product in the history of Shell Aviation.

Our customers didn’t want an oil that was just adequate - they demanded a new, innovative product to match the exacting requirements of today’s turbine engines.

So our dedicated team developed our prototype oil and put it through an exhaustive programme of tests. And the results were ground-breaking: AeroShell Ascender sailed through the toughest tests in a manner that’s almost unprecedented.

For example, in the industry-standard Elastomer Test, AeroShell Ascender lasted almost twice as long as other competitors’ oils in tests with fluorocarbon elastomers. AeroShell Ascender also passed every other test comfortably: coke deposits were considerably reduced and engine seals lasted longer.

Developed and tested without compromise, we believe that AeroShell Ascender represents a new benchmark for High Performance Turbine Oils. 

AeroShell Ascender - The oil your engines have been waiting for

But AeroShell Ascender hasn’t just set a new standard for HPC oils - it can also help take your business to a new level.

The advantages of AeroShell Ascender’s advanced formulation translate into:

  • Minimal downtime
  • Greater reliability
  • Reduced maintenance costs
  • Better performance – in the air and on the balance sheet


Greater balance and protection, less coking, improved engine stability, increased mechanical confidence: these all add up to a solution that will keep both engineers and financial controllers happy.

Oil compatibility change-over procedure

Image of a plane

When changing from one approved oil to another, the recommended method is to change by ‘top off’ during normal servicing of the engines, and is the method preferred by the majority of engine manufacturers. Field experience and laboratory testing have demonstrated that this method has the least impact on the engine and helps maintain the equilibrium of the oil system.

However operators should always refer to the engine maintenance manuals or service bulletins to confirm that the ‘top-off’ method is acceptable for their specific engine type.


The next generation of aircraft is on the runway. And so is the next generation of High Performance Turbine Oil.