Inside Jet Engines – Power, Precision, and the Parts You Never See

With Robertas Ruzgas, Engine Material Sales Manager at Magnetic Trading

Most people board an aircraft without giving much thought to what’s keeping it in the air – beyond the wings and maybe the engines. 

But behind every safe flight lies an intricate world of parts, performance, and precision. 

And that’s where Robertas Ruzgas, Engine Material Sales Manager at Magnetic Trading, comes in.

Robertas helps airlines, MROs (Maintenance, Repair and Overhaul providers), and lessors find the critical engine parts they need to keep aircraft in the sky. 

That might sound pretty straightforward – until you realize the sheer complexity of jet engines and the logistics involved in sourcing rare, high-demand components from around the world.

“I often say that selling airplane parts is like selling car parts,” Robertas jokes. “Except,  instead of tires and brake pads, you’re looking for superalloys that can survive near 1,000-degree temperatures.”

At Magnetic Trading, Robertas is more than just a salesperson – he’s a problem-solver – and he’s here to help us demystify one of the most advanced technologies on Earth.

Breaking Down a Jet Engine

Engines like the CFM56, widely used on Airbus A320 and Boeing 737 aircraft, are made up of thousands of highly specialized components. Some, like compressor and turbine blades, endure extreme stress and temperature. Others, like bearings or seals, ensure the entire system stays balanced and safe.

“The parts that live in the engine’s hot section are always in demand,” says Robertas. “Even though they’re made from materials developed in advanced laboratories – called superalloys – they still degrade over time.”

Dust, sand, and other microscopic debris can erode first stages of compressor blade surfaces at high speed. As these parts wear out, they either need to be repaired or replaced. For Robertas and his colleagues, it’s a constant race to stay ahead of global demand – especially now.

“Right now, it’s particularly tough to find life-limited parts for CFM56-7B engines with more than 10,000 cycles left,” he explains. “Everyone wants them, but they’re in short supply. That’s where we step in.”

When Size (and Efficiency) Really Matter: The GE90-115B

Sounds powerful, right? The thing is, despite being the most common engine variant flying in the world today, well, the CFM56 is the equivalent of a Toyota Corolla. 

It’s super popular, very reliable, relatively cheap (in aircraft engine terms, at least), and does the job it’s needed for. But it’s no Ferrari.

The GE90-115B, a monster of a machine developed by General Electric for some variants of the Boeing 777, is one.

It produces 115,000 pounds of thrust – one of the most ever for a commercial jet engine. And it weighs nearly as much as a medium-sized city bus.

“If you’ve ever flown on a 737, just imagine this: the GE90 engine’s fan diameter is nearly the same as the cabin width of the 737 itself, so you can imagine how big the fan of this engine is,” says Robertas.

The GE90-115B engine was designed to deliver massive power, enough to launch a plane capable of taking off at over 351 tonnes with over 400 passengers, while remaining efficient. 

You see, with engines, it’s all about the bypass ratio.

This is the ratio of the amount of air that flows around the engine’s core (the “bypass” air) to the amount that goes through the core (where compression and combustion happens). 

The bypass ratio (BR) refers to the mass of air, measured in kilograms, that flows around the engine core compared to the amount that passes through it. In general, newer engines have higher bypass ratios. 

To improve efficiency and achieve better BR, manufacturers design engines with larger fans. For instance, the GE90-115B features a massive fan and achieves a BR of 9:1, while the older, smaller-fan CFM56-5B4 has a BR of 5.7:1. 

Some of the latest jet engines, such as the CFM LEAP-1A and the PW1100G-JM – both developed for the A320neo – reach bypass ratios of 11:1 (CFM) and 12.5:1 (PW), respectively.

A higher bypass ratio means more air is moved by the fan around the outside of the engine core rather than through the compressed and hot, fuel-burning sections. This is important because moving a large volume of cooler air is much more fuel-efficient and quieter than relying only on the hot jet exhaust for thrust. 

That’s why commercial aircraft like the Boeing 777 use high-bypass turbofan engines – they’re optimized for efficiency and lower noise, especially at subsonic speeds.

From Dubai Dust to Arctic Cold: An Engine’s Life Story

Every jet engine has a past. From desert heat in the Middle East to freezing cold in Northern Europe, engines rack up millions of miles and thousands of flight hours. Understanding this history is critical when evaluating an engine or its parts.

“You can learn a lot from an engine’s documentation. We can see what climate it operated in, which airlines used it, what repairs were done, and when. Sometimes it’s all crystal clear. Other times, it’s like a forensic puzzle.”

And the deeper the history, the more important the paperwork. Robertas notes that after years of scans and transfers between owners, some documents are hard to read or even missing. That’s when the real detective work begins.

“That’s when you really need to be a searcher,” he adds. “Finding the right part is just one part of the job. Finding its full story is the hard part.”

What Surprises People Most?

Aircraft engines may look securely mounted on a wing – but they’re actually designed to detach under extreme conditions.

“People are always shocked to learn that engines are mounted at just three or four points,” Robertas says. “But it’s a safety feature. In the unlikely event that the engine comes loose, it is designed to break away to prevent damaging critical hydraulic and fuel lines in the wing.”

It’s a reminder that aviation isn’t just about performance – it’s about fail-safe performance. 

Every component, every bolt, is engineered with both excellence and safety in mind.

Tiny Changes, Massive Impact

The aviation industry is on a constant quest for efficiency. Even minor improvements can have enormous financial and environmental impacts.

“A 1% fuel saving on a long-haul aircraft can translate into millions of dollars over a year, and that’s just one aircraft. Multiply that by an entire fleet and you can see how meaningful it becomes, both for profits and for the planet.”

This is why part quality, sourcing, and lifecycle tracking are more important than ever. It’s not just about flying – it’s about flying smarter.

Major engine manufacturers have been working for decades to answer the question of how to save more fuel and build more sustainable engines. CFM envisions creating an engine capable of reducing fuel consumption by up to 20% compared to today’s models. 

Initiatives such as the Revolutionary Innovation for Sustainable Engines (RISE) program aim to transform conventional engine design by utilizing an open-fan architecture. As ducted engine designs approach their efficiency limits, open-fan technology offers the potential to achieve entirely new levels of performance. 

The CFM RISE engine, for example, could achieve a bypass ratio five times greater than that of the most advanced ducted engines in operation.

Finding Power in the Details

Robertas’ role at Magnetic Trading goes far beyond procurement. It’s about trust, precision, and solving puzzles others walk away from.

“You really need to enjoy the hunt,” he says. “Sometimes you’re the only one who can find the missing part, or the missing document, and get a grounded aircraft back into the air. That’s a great feeling.”