Pattakon engine.....legitimate alternative or just another fly-by-night

[manolis]

Copy from a post to another forum:

“A few months ago I found this picture in Trek Aerospace web site.



According their technical data: there is a rotary 118 PS engine, the empty weight of the flying machine is 167 Kg, and they use a lot of electronics to stabilize-drive this vehicle . There was also a price catalogue.
I see no reason for not fly such a “private” helicopter. Do you?


The idea behind the Pattakon’s flying machine is quite different than making a small helicopter. The simplicity and the small weight is what counts high yonder. The body of the pilot, just like the body of the rider on a bike, feels and responds and so “drives” the vehicle.

By the way, the two crankshafts of the Junkers-PRE is an advantage for this application (a single crankshaft engine is problematic, think why). “


Besides laughing, consider the freedom and the change a portable flyer could bring to the world.

Thanks
Manolis Pattakos

[CHOOK]

Originally Posted by manolis

Besides laughing, consider the freedom and the change a portable flyer could bring to the world.

I think more of the practicality, safety and demand for such a machine. I can't see myself flying to work in the near future. Imagine the road rage.....or would it be sky rage

But if that is the market you want to capture, good luck.

BTW there are quite a few questions on the first two pages that you have conveniently missed. It is only two pages of reading if you care to go back and review. This thread is your big chance to answer all the doubters.

[lightweight]

Ok, interesting conversation.

Going back to the pdf I promised you all.

The whole issue is 17 mb, and the limit for pdf attachment is below 500 kb. I can upload only the pattakon article.

My question is how to separate these pages from the rest of th pdf? I have acrobat professional if this helps.

[Matra et Alpine]

with pro it's dead easy . just save multiple pages rather than whoel document. Choosing the number of pages in each file so the size turns out to be 500Kb
The other option is to save at much lower resolution, but you'll struggle to get 17Mb down to 500K

[lightweight]

Originally Posted by Matra et Alpine

with pro it's dead easy . just save multiple pages rather than whoel document. Choosing the number of pages in each file so the size turns out to be 500Kb
The other option is to save at much lower resolution, but you'll struggle to get 17Mb down to 500K

I can't extract pages out of the document, as this requires a password (which I don't have).

I can't seem to understand how I will save only 1 page.

[CHOOK]

Originally Posted by lightweight

I can't seem to understand how I will save only 1 page.

Use the Print Screen button and copy it into Paint and create an image.
There is a way around everything

[revetec]

Originally Posted by manolis

By the way, the two crankshafts of the Junkers-PRE is an advantage for this application (a single crankshaft engine is problematic, think why). “

Besides laughing, consider the freedom and the change a portable flyer could bring to the world.

Thanks
Manolis Pattakos

But running propellers off the shafts like your families design does not allow for rotation and pitching side to side, or even static rotation. It will be interesting to research and discuss how it must be done.

Here is a quote from their website:

Trek Aerospace's Springtail Exoskeleton Flying Vehicle is a single operator powered-lift vehicle that supports the operator/pilot in a standing position. There are a pair of ducts, approximately one meter in diameter, mounted on the upper end of the airframe above the operator. Each duct contains a fan consisting of five blades which produce thrust in the vertical direction. The fans are counter-rotating, eliminating the torque that is normally associated with a single rotor. The ducts and fans tilt, individually, about a common axis for pitch and yaw trim. Vanes mounted in the ducts, just below the fans, are used for directional control. The power plant for the aircraft is mounted on the airframe to the rear of the operator. The vehicle is operated by an advanced fly-by-wire computer control system.

Control System

We have developed a computerized fly-by-wire system which has been fully tested on Springtail. This proprietary onboard computer hardware and software helps to ensure maximum craft performance and pilot safety. Three-axis directional control is achieved through vanes which are mounted in the ducts. Depending on the application, the duct and fans can be rotated for additional control. We have also integrated a three-axis gyro for applications where control on all three axes is necessary. Because the system is computer controlled, advanced attributes such as a built-in GPS guidance control, a collision avoidance system, and position, altitude and direction feedback are all possible.

[drakkie]

Originally Posted by manolis

By the way, the two crankshafts of the Junkers-PRE is an advantage for this application (a single crankshaft engine is problematic, think why). “

Thanks
Manolis Pattakos

For your information, Junkers is a big company from Germany. They might not be too happy with you naming it like so. I could not find anything on their website about this. It seems highly unlikely you have their cooperation on this, becuase they are not active in the engine business.

Just warning because it can cause you serious trouble and lawsuits and the lot.

[santostripoli]

Team

Please review this analysis of the Pattakon engine that I sourced.

It was calculated using a standard combustion peak pressure. It was much worse in alloy. Steel mass 1.228kg with an alloy piston.

Comments anyone?

[revetec]

This piston assembly has to be able to deal with the same loadings that are experienced with a conventional con-rod. I would expect that this has been overlooked, and I imagine that the piston assembly will have to be strengthened and made about double the weight of a conventional assembly looking at the analysis.

[CHOOK]

Originally Posted by santostripoli

Please review this analysis of the Pattakon engine that I sourced.

Sheeesh I wouldn't want to be 50 metres up in one of those Human Helicopters with all that strain on the engine.

[santostripoli]

Originally Posted by CHOOK

Sheeesh I wouldn't want to be 50 metres up in one of those Human Helicopters with all that strain on the engine.

Here is yet another analysis that I have found. This one assesses the shaft. According to this diagram, the multi cylinder versions will increase the twisting load and it is calculated that the shaft will fail at no more than half of normal loadings with a safety factor of 0.476 (1 = pass 1.2-1.5 acceptable).

Manolis, you have some issues to contend with here!!!

[revetec]

People in glass houses shouldn't throw stones eh?

[santostripoli]

Originally Posted by revetec

People in glass houses shouldn't throw stones eh?

Weight analysis shows the Pattakon Pulling rod engine’s reciprocating components being 130% heavier than the conventional using the same materials.

Calculation was based on parts measuring the same as their diagram and the comparison was made between the con rod and piston on the conventional compared to the piston connecting plate and con rod on the Pattakon design.

[CHOOK]

That's great work Santo.

Maybe Manolis can concentrate his time on addressing these kind of issues with his family's engine rather than waste time trying to find deficiencies in others (with no luck at all mind you).

Also, Pattakon should employ you for doing all the stress analysis for them.
Maybe you can train their 50 engineers