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Blades of glory: the world’s first 11-bladed propeller

Blades of glory: the world’s first 11-bladed propeller

February 05, 2023

We caught up with one of the team behind the development to talk about why they did it and what exactly they want to do with it.

This idea has been in the pipeline since 1968, and is now finally coming to fruition
The team is working with power plant manufacturers to design the correct gearbox or electric motor to run with a max rpm of 1,000 -1,200, to make this as efficient an addition to an aircraft as possible
The 11-bladed propeller made a big splash in the news, so the team is now discussing its commercial development

THE BLUEPRINT ILLUSTRATION

THIS WEEK’S MUST READ

Blades of glory: the world’s first 11-bladed propeller

The world's first 11-bladed propeller recently successfully completed its first test flight, its developer MT-Propeller said. This marks yet another first for the developer, which has also produced five, seven, and nine-bladed propellers.

The propeller on an aircraft converts the rotational energy of the engine into a propulsive force or thrust. The amount of thrust produced by the propeller is proportional to the blade area, while the number of blades determines the pulses of thrust that the aircraft produces for each revolution of the propeller.

Founded in 1981 by Gerd Mühlbauer, MT-Propeller has more than 27 certified propeller designs to its name, and over 220 aerodynamic blade designs. The company claims that it supplies propellers to over 90 percent of the aircraft produced in Europe that use a piston or turbine engine.

Last fall, MT-Propeller first tested its 11-bladed propeller design on the Piper PA31T1 aircraft, which was equipped with Pratt & Whitney PT6A-135A turbines.

The first flight took to the skies with “an impressive noise and sound signature.”

Take a look at the test here – it may look small, but it took to the skies like a twin-engine jet. Pretty cool.

But beyond how neat it looks, the science is fairly impressive too, as Martin Albrecht, vice president of MT Propellor, explains: “Our propeller design team observed a 15 percent increase in static thrust with the new propeller when compared to the five-bladed propellers we’ve made before.

“We are hopeful that the aircraft propeller system, combined with a low rpm power supply, could open up new possibilities for performance, efficiency, and noise. The low-rpm power supply could come from a turbine or even an electric engine.”

Interesting Engineering: What prompted this research in the first place?Martin Albrecht: MT-Propeller has been working for years on making propellers more efficient – as well as quieter and lighter.

Gerd Muehlbauer started it all – this company and the seeds of the idea. MT-Propeller Gerd Muehlbauer GmbH was founded in 1980 by Gerd, who came to it with 20 years of experience in propeller development and service under his belt.

He actually started thinking about this 1968, when he was working as a Chief Engineer for a different company. But he needed to found his own company to have the freedom to explore the engineering elements without there being any big commercial interest, so that’s what he did.

His work has also led to a new acceptance of the concept by aircraft operators and passengers, which just wasn’t there before.

IE: Did you achieve what you set out to achieve? MA: Yes, we demonstrated that such a propeller can be built, flown and behaves like a propeller with no downsides. Now, we are going to look into the benefits of this new design in relation to top speed and noise.

IE: Were/are there any other aims to the work that you have yet to achieve?MA: At this point no.

The story continues...

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THIS WEEK’S MUST READ

The story continues...

What barriers stand in the way of you making this commercially available?

We are working with power plant manufacturers to design the correct gearbox or electric motor to run with a max rpm of 1,000 -1,200. We want to make this as efficient an addition to an aircraft as possible. Of course, this design is partially dependent on the rpm from the power supply.

What sort of time scale do you anticipate before (if) you can make that happen?

We have already certified, commercially introduced and are successfully selling the 7-bladed propeller for several applications. The 9-blade version is already built and in an R&D program with a big engine manufacturer. The 11-bladed propeller definitely made the news, so now we are talking to potential power plant people about its commercial development.

What are you and the team working on now, as a result of this work?

Analyzing the flights, aerodynamics, optimizing our software codes. There’s lots to do!

Quickfire questions

What or who inspires you?

A huge interest in engineering. Also having fun making new products that we can then make into a commercial success.

In the last 25 years, our company has grown by 20 times simply by following this route. Again, the driving point is always engineering a more modern system – higher efficiency, lower noise. If we achieve that the market will give us a huge amount of recognition.

What gets you out of bed in the morning?

The alarm I set the day before.

What makes you smile?

The answer I just gave you.

What is your greatest achievement to date?

Not sure, beside being an engineer, being a Test Cat 1 test pilot with 7 German unlimited aerobatic championship wins with three European 3rd places. So far nobody else has achieved that, so I’m pretty proud of it.

What is your biggest regret?

None.

What would you say to someone wanting to follow in your footsteps?

Go ahead – do it. The world needs better engineering for a better future in every industry and for every aspect of life.

What advice would you give your younger self?

Just follow your interests and your ideas. Trust yourself.

WEEKLY POLL

Blades of glory: the world’s first 11-bladed propeller

What do you think is the main barrier to 11-bladed propellers becoming commercially available? (Poll closes 8 February)

Cost

Scalability

It's not commercially practical

Something else entirely

LAST WEEK'S RESULTS

Last week, we asked you where you think the metaverse will make the biggest impact in years to come, and while 33 percent of you said education, 33 percent said it'll be something else entirely.

33%

Education

33%

Something else entirely

17%

Gaming

17%

It won't make an impact