Sunday, December 28, 2008

Angelo Di Pietro’s Amazing Rotary AIR Engine

For: Running on Air
By: Boom San Agustin

As I was browsing the web studying more and more about the AIR ENGINE, I stumbled upon a Rotary-type Air Engine that claims to have outstanding efficiency, constantly high torque, low parts count, is compact and light, with virtually no vibration, has smooth speed control and is virtually frictionless! In fact, it only takes 1 PSI of pressure to overcome friction! You read it right; only 1 PSI! I’m talking about ANGELO DI PIETRO’s AMAZING ROTARY AIR ENGINE!

In his website, Angelo Di Pietro says, "There is no other motor as good as ours, years of research and analyzing other motors around the world gave me the confidence and obligation to say so. (By) ‘Obligation’, (I mean,) in the sense that people have been waiting for ages in relation to efficiency in order to take care of our environmental situation.” Now, “100% more efficiency than the competitors” is a very serious claim! It almost sounds like a challenge or some kind of publicity stunt in order to market their engine! But Di Pietro is very confident in claiming that his invention has a long list of important improvements over other motors and that his concept has the capability to change the way we use transportation and furthers the benefits we get (in terms of energy savings) from the motor’s stationary applications. Are his claims valid? Let’s, first, review his engine design.

Engine Design and Fuctionality:

Di Pietro’s motor concept is based on a rotary piston. Different from existing rotary engines, the motor uses a simple cylindrical rotary piston (shaft driver) which rolls, with virtually no friction, inside the cylindrical stator. The space between stator and rotor is divided in 6 expansion chambers by pivoting dividers. These dividers follow the motion of the shaft driver as it rolls around the stator wall. The motor shown is effectively a 6 cylinder expansion motor. The cylindrical shaft driver, forced by the air pressure on its outer wall, moves eccentrically, thereby driving the motor shaft by means of two rolling elements mounted on bearings of the shaft. The rolling motion of the shaft driver inside the stator is cushioned by a thin air film. Timing and duration of the air inlet and exhaust is governed by a slotted timer which is mounted on the output shaft and rotates with the same speed as the motor.

Varying the performance of the motor can be achieved manually by varying the time during which the air is allowed to enter the chamber; meaning, a longer air inlet period allows more air to flow into the chamber and therefore results in more torque; while a shorter inlet period will limit the air supply allowing the air in the chamber to perform expansion work at a much higher efficiency. This way, compressed air consumption can be varied for higher torque and power output depending on the requirements of the application. Motor speed and torque are simply controlled by throttling the amount of air pressure into the motor. The Di Pietro Motor boasts that it gives instant torque at zero RPM and can be precisely controlled to give soft start and acceleration control.

Di Pietro’s Engine put to the Test by Melbourne Market Authority:

In August of 2004, Di Pietro, through his company, ENGINEAIR (in Brooklyn, Victoria) made good on his claims by developing “Market Burden” Carriers (vehicles used in ‘wet’ markets to carry heavy cargoes of goods from one point of the market to another), powered by his Air Engine for the Melbourne Market Authority (which operates a fleet of almost 300 Carriers hired by the market's users to collect and transport their choice of fresh fruit and vegetable produce from the wholesalers around the market) to be used in Melbourne’s Wholesale Fruit & Vegetable Market! Two (2) stroke petrol engine powered Carriers were being used by the Melbourne Market Center for the wholesale transport of fruit, vegetables and flowers over a massive 31 hectares of market. In an enclosed area, such as the market place, the emissions from the petrol engine carriers usually cause a variety of diseases to the vendors and patrons of the market! But since air drives Di Pietro's motor without any combustion or exhaust gases, his Carriers achieve zero-pollution mobility; which is an ideal concept for enclosed areas such as markets, factories or warehouses.

Di Pietro’s Carriers must have impressed the Melbourne Market Authority since it has offered ENGINEAIR a grant to develop and build prototypes for new Carriers driven by Air Engines.

This information may be verified with the Melbourne Market Authority, through David Traficante via telephone (03-9258-6161); or via E-mail (

Angelo Di Pietro (Brief History):

Angelo Di Pietro, (1950, Avellino, Italy) qualified as Congegniatore Meccanico in Avellino moved to Stuttgart, Germany to work on the Wankel rotary engine at the Mercedes Benz research laboratories 1969 and 1970. In 1971 he migrated to Australia where he established a construction engineering company there. From his early experience with Wankel Rotary Engines, Angelo became interested in developing a more efficient engine than the traditional reciprocating internal combustion engine, and he has worked on various alternative concepts intermittently over the last 30 years. In 1999 he made a major design breakthrough. Recognizing the potential of his invention Di Pietro decided to fully focus on the development of the new motor concept. The principle worked with the first prototype and, although not built to fine engineering tolerances, its performance far exceeded expectations.

Engineair Pty Ltd. (Company Profile):

Engineair Pty Ltd, established on 9 September 2000, with the objective to perform research and development on an innovative air motor design, invented and first tried by Di Pietro in 1997. In the first 2 years the company focused on developing prototype models to test the concept and understand the performance characteristics. During this period additional prototypes were tested, showing improving performance, power to weight ratio and air consumption. The current development status shows performance and efficiency to be superior over state of the art air motor technology. Based on these results the company is now entering commercialization of its technology. Engineair operates from modern dedicated facilities in Brooklyn, Victoria (close to Melbourne City). It houses facilities with an area of 1100 sqm (office and workshop area) and includes state of the art test and performance measurement systems.

Source: ENGINEAIR Pty, Ltd.


Below is a ‘YouTube’ video of a 2004 Report on Angelo Di Pietro’s Air Engine. Enjoy!


Boom San Agustin said...

I posted a VIDEO at the end of the article. It's a video of a 2004 Report on both Guy Negre’s Air Car (which you already know about) and Angelo Di Pietro’s Air Engine. The report on Di Pietro’s Engine comes near the end of the video, AFTER the report on Negre’s Air Car; so, just keep watching the video ‘til the END!

didier said...

Yes, this engine claims to be much better than the MDI one. Lighter, smaller, more efficient... All the same, I have never seen a video of a car running with this Di Pietro engine. You? I gather Enginair has the problem that has been MDI's for many years: a severe lack of cash to go on developping. If their claims are founded, then I can only hope that soon MDI and Enginair will come to an agreement to work together, to the benefit of a much better air car and of our planet. Being high time as it is, the air car needs to have really good performances and especially a nice range. We cannot afford this project to fail. Therefore, gentlemen, please join forces, that is ... if this rotary engine technology really holds water. For from a small and slow vegetable market garden there is quite a step to a performing family car!
I questioned one technological expert on the French air cars forum, and he states that lubrication and sealing are the two main problems of this type of engine. There's also the Quasiturbine, that is similar, being also a rotary engine, but here compressed air is only one of its possible fuels. For a list, explanations and links about the compressed air engines other than MDI, have a look at the page "others" of
Happy New Year!

Boom San Agustin said...

@didier: I don't think it was actually designed for automobiles just yet. But as an Electric Generator (running on a solid base), this Engine looks perfect for the job! ;)

gege said...

Boom, mi amigo. Yo no soy marinero. Yo no soy marinero, soy capitan
Soy capitan, soy capitan. Bamba, bamba.

Congraciolaciones para tu bloggida en espanol!


Anonymous said...

My understanding of the Melbourne Market grant for the air car is that the grant was given to produce a prototype for the market. However, the testing hasn't yet been completed due to certain internal problems. Where is the report on its superb performance in the market and orders for more?
Great idea, but is still waiting to gain momentum.

Boom San Agustin said...

Hi Anonymous Person... ;)

I see where you're coming from. However, please allow me to give you an update on what's been happening behind the scene...

1. Di Pietro's Motor will now be manufactured in China! I got this straight from Angelo himself; but I also verified this with several contacts I have in China. It looks like a "go" for this engine!

2. My company and some of my friends (angel investors) have already witnessed how this engine works and are now into negotiations to bring this technology into the Philippines. This is already a "go"!

3. I don't know about the performance report from the Melbourne Market; but the only problem we saw was when the motor was used in moving vehicles; but since that is not how we plan to use it, this engine is perfect for us.

I hope this helped, Anonymous! :)

Anonymous said...

When going to Thailand?

Boom San Agustin said...

Hi there Anonymous Person-2! ;)

We don't have word as to how things are shaping up in Thailand. But, if you're from Thailand and if you want this technology to reach your country, then why don't you try to be the first to advocate it there.

You can also go to the Engineair website ( and inquire with them directly.

I hope this helped...


Anonymous said...

i think it was :

can u buy this engine in china ?? where ???

Boom San Agustin said...

Hi Again Anonymous Person 2,

I'm not sure if you can buy this in China. All I know is that in my last conversation with Angelo Di Pietro (several months ago), he mentioned that he would have his engine manufactured in China since it was cheaper to do it there. I really don't know what transpired after that.

But I'm flying to Australia next month and one of the main reasons I will be going there is to acquire a "license to sell" from ENGINEAIR. I'll try to contact Angelo before the trip. I'll also try to get an answer to your question and post it here.

Thanks again for posting your comment!

Anonymous said...

One way on increasing the performance (longer duration than 2 hours of use) of the engine is to have extremely cold air pumped into the onboard tank of the vehicle. You can get more cold compressed air into the same sized chamber than the normal air. Also the cold air will have moisture (or added lubricate of some type from the main feeding tank) to lubricate the engine better, thus decreasing the friction even further. The cold air will heat up from the motion of the internal area and then be more easily expelled out the exhaust port. In essence lubricating the engine and increasing the run time of the engine as well.

Sheldon Gesell (Manitoba, Canada)

Boom San Agustin said...

Hi Sheldon,

Man, have I been busy! Sorry that I didn't reply to you sooner.

You're absolutely right about the cold air. But I don't know how we can keep the air cold. Anyway, I wouldn't really worry about it. Di Pietro's engine gives good torque at just 1 PSI.



Max said...

Hello Boom San Agustin,
I am a junior year Mechanical Engineer and I am very interested in using this air motor in my senior project, which will be to design and build a compressed air powered motorcycle (ambitious I know). I was wondering where/if I could find technical specifications on the motors performance? Or if you knew if there is a version of the motor that is either available commercially or that Mr Di Pietro would be willing to provide for my project? Any information at all on this subject would help me greatly! I am hopefully going to formally approach Mr Di Pietro's company sometime soon about the project. I'm really excited about getting started making the bike.

tony said...

how can i access one of these motor.

tony said...

would like one of these motor.
whats the cost?

Dissenha said...

Hello San Agustin,
I have been following this Di Pietro engine already for years and I still think about that as a solution for small city cars - same for MDI cars.

However, still is not clear if to over come the internal friction the engine needs only 1PSI (0,07bar) how is the preassure we need in the tank to a "smoothly" driving let's say around 60km/h for 1 or 2 hours? How is the consumption (lts/h) for that engine? how is the max torque and min at 1PSI?
How is the rotation range x torque? The general dimension to fix it onto a chassi or axel? I mean, Di Pietro has all my respect for his invention but come-on before all he is a Engineer...those are basic requirements for any application.
I have a real intention to buy such engine and to test it, but I do not have even the price or if he has the intention to sell it for real...
btw, In case you go for a license as you mentioned, better you have those technical information in your hands too.

All my best regards

Anonymous said...

Great thoughts you got there, believe I may possibly try just some of it throughout my daily life.

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Sonia said...

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Ali Potter said...

What I'm wondering, is if the engine can run in reverse as a compressor, if so, and given its size, why can't a compressor version be sited on every wheel as a brake - repressurising the air tank as the vehicle slows. I'm also wondering about the pressure of the 'exhaust gas' - railway steam engines operate on a triple-expansion principle, where progressively less pressurised steam entered gradually larger piston chambers, extracting useful work at each expansion stage. Could a second or third stage expansion 'ring' be added to the existing engine to extract more work from the gas?
This is the way forward.