New rotors and rotor blades

Trendak&Son

Gyroplane Manufacturer
Joined
Dec 2, 2013
Messages
137
Location
Jaktorow, Poland
We are in the process of developing new rotors for gyroplanes. Two new profiles 9H12 MODIFIED and ILW-LT-11.0 were prepared in cooperation with Institute of Aviation in Warsaw within the joined project Modern Autorotative Rotor.

The first complete rotors with aluminium extruded blades have been manufactured and will be undergoing intensive flight testing this season.

Once the new blade profiles are evaluated as advantageous as compared to traditional 9H12 profile, the development of composite carbon rotor blades utilizing the new profiles will follow.
 

Attachments

  • Rotor Trendak 1.jpg
    Rotor Trendak 1.jpg
    35.6 KB · Views: 5
  • Rotor Trendak 2.jpg
    Rotor Trendak 2.jpg
    43.7 KB · Views: 5
  • Rotor Trendak 3.jpg
    Rotor Trendak 3.jpg
    68.9 KB · Views: 5
  • Rotor Trendak 4.jpg
    Rotor Trendak 4.jpg
    125 KB · Views: 5
In the process of certification of our new Tercel gyroplane in Germany we also developed a new rotor head with build in conning angle, as stipulated by BACR T and BUT.
 

Attachments

  • Tercel Trendak Rotor 1.JPG
    Tercel Trendak Rotor 1.JPG
    43.3 KB · Views: 6
  • Tercel Trendak Rotor 2.jpg
    Tercel Trendak Rotor 2.jpg
    39.5 KB · Views: 5
  • Tercel Trendak Rotor 3.JPG
    Tercel Trendak Rotor 3.JPG
    36.2 KB · Views: 4
  • Tercel Trendak Rotor 4.jpg
    Tercel Trendak Rotor 4.jpg
    56.5 KB · Views: 4
I think this new profiles was presented in Germany early this year already ?

"advantageous as compared to traditional 9H12 profile" - traditional for gyrocopters is 8H12 profile, not 9H12

community appreciate your, Artur, tries and IMPROVEMENTS (for sure), but be EXTREMELY carefull with all those "improvements" - they coudl bring SIGNIFICANT SECURITY RISKS, also, from experiance, I'm not sure that utilization of students financed by governmetal funds (free man power - let state the truth...) will bring you somehwere ...

Live example (of fine tuning in univercity and security) is Ukrainian helicopet AK 1-3 - rotor system was also "fine tuned" in Aviation Univercity of Kharkov for PERFORMANCE (whyle autorotation was ... forgotten) result: 40 produced helicopters and 30 already destroyed....


BY THE WAY - WHAT ARE YOU TRYING TO ACHIEVE WITH NEW "ADVANTAGEOUS" ROTOR ?
 
Last edited:
On the other hand, German University Akafleig groups have not only designed but built some very successful designs. Think first grp aircraft.

Dino
 
I think this new profiles was presented in Germany early this year already ?
Yes, you are right, at AERO 2014 in Friedrichshafen we presented some cut-outs of the blade profiles for easy comparison.

Now we are at the stage when full scale manufacturing was started and substantial numbers of blades and rotor can be tested on different testing rigs.

community appreciate your, Artur, tries and IMPROVEMENTS (for sure), but be EXTREMELY carefull with all those "improvements" - they coudl bring SIGNIFICANT SECURITY RISKS, also, from experiance,
Thank you for your appreciation and warning. We will take it into consideration.

I'm not sure that utilization of students financed by governmetal funds (free man power - let state the truth...) will bring you somehwere ...
You have completely wrong concept of the project. There are no "students" involved.
The cooperation is with the Aviation Institute in Warsaw, which is not an educational, but pure research and development institution. These are experienced scientists, the Institute itself has almost 88 years of history of successful designs. (It has been established on August 1st, 1926).

The team involved has participated on such successful projects as SW-4 Puszczyk and W-3 Sokół and Anakonda helicopters.
Recently they developed an UAV helicopter ILX-27.

They have large scale wind tunnel and and rotor testing facilities available.

More here: http://ioa.edu.pl/

Live example (of fine tuning in univercity and security) is Ukrainian helicopet AK 1-3 - rotor system was also "fine tuned" in Aviation Univercity of Kharkov for PERFORMANCE (whyle autorotation was ... forgotten) result: 40 produced helicopters and 30 already destroyed....
We prefer not to comment on projects of other companies without having first hand knowledge.

BY THE WAY - WHAT ARE YOU TRYING TO ACHIEVE WITH NEW "ADVANTAGEOUS" ROTOR ?

The theoretical calculations on the new profiles are predicting improvement of app. 10 knots in cruise speed and 10% reduction in fuel consumption on any given application.

The NACA 8-H-12 profile has been optimized for low rpm autorotational effectiveness, allowing hand starting the rotor or using a very weak prerotators with low prerotation rpm. It has been a trade off for performance. Modern gyroplanes use powerful prerotators and the rotors cannot be usually hand started from an enclosed cabin.
 
Last edited:
I will put some jokes to this serious discussion

Hmmm, so is it 9H18, 9H12 or 8H12?
Cheers Cam.

it's a SECRET known only in Aviation Institute in Warsaw :) little bit of MISTERY always good ... in MARKETING....but not in AERODYNAMICS :)

let's wait test result (real ones, not marketing ones) of this new 8/9-H-12/18 airfoil ;)
 
Last edited:
Yes, you are right, at AERO 2014 in Friedrichshafen we presented some cut-outs of the blade profiles for easy comparison.
easy comparison of your "new" airfoils
 

Attachments

  • DSC_0783.jpg
    DSC_0783.jpg
    67.5 KB · Views: 5
Hmmm, so is it 9H18, 9H12 or 8H12?

To lay to rest all confusion:

- the traditional gyroplane blade profile is NACA 8H12

- the first tested Trendak blade is 9H12 MODIFIED

- the second tested Trendak blade is ILW-LT-11.0

I hope it helped.

I think, it is also worth mentioning, that the new blades are 220mm chord.

attachment.php
 

Attachments

  • Rotor Trendak 1 small.jpg
    Rotor Trendak 1 small.jpg
    14.9 KB · Views: 4
Last edited:
...
"advantageous as compared to traditional 9H12 profile" - traditional for gyrocopters is 8H12 profile, not 9H12....[/B]

The 9H12 MODIFIED profile is a further development of the 9H12 profile, which certainly can be called "traditional", since it is used for over 70 years.

You can find more in this interesting document from 1946:

http://naca.central.cranfield.ac.uk/reports/1946/naca-rb-l5k02.pdf

From the document summary:

Four NACA airfoil sections, the NACA 7-H-12, 8-H-12, 9-H-12, and 10-H-12, suitable for use as rotor-blade sections for helicopters and other rotary-wing aircraft have been derived and tested. These airfoil sections have comparatively low drags in the range of low and moderate lifts and small pitching moments that are nearly constant up to maximum lift.
 
Last edited:
do you have already some test results (that you could share publicly) for this new blades ?

some comments / questions :

- experts in Institute of Aviation in Warsaw are most probably experts of COMPOSITE BLADES (today helicopters world), you try to reinvent ALUMINIUM BLADES.
ALUMINIUM EXTRUDED blade, is absolutely different story to COMPOSITE BLADES...in COMPOSITE BLADE you could achieve any (nearly any) characteristics THAT YOU WANT, in ALUMINIUM (extruded) blade - you are VERY LIMITED and need to search for COMPROMISE. Those competence in COMPOSITES BLADES will not help you significantly here (in other words - if you pay for this research, most probably this is money for nothing...)

- probably airfoil you choose/develop with Institute of Aviation in Warsaw will bring some benefits...but many questions to the CONSTRUCTION to the ALUMINIUM BLADE itself (design of extrudat as it is today - I guess you have many challenges with vibration of new blades (already on low speed), compare to the old blades) - did I guess ? I'm not the expert...but from first look it seems that this ALUMINIUM blade will be never dynamically balanced (due to the design of this extrudat itself...)

- 220mm of chord - not too much for "light" Tercel ?

- from which material (aluminium alloy) your new blades are extruded ?
 

Attachments

  • needtoberedesigned.JPG
    needtoberedesigned.JPG
    23.9 KB · Views: 3
Last edited:
Leon, it is hard to make sense of your rush to criticize this new design. Your user profile tells us little about your expertise or possible agenda.

Trendak has already stated aluminum is a development step with an ultimate goal of carbon fiber construction. I'm interested to see what this proven team can do.
 
Leon, it is hard to make sense of your rush to criticize this new design. Your user profile tells us little about your expertise or possible agenda.

Trendak has already stated aluminum is a development step with an ultimate goal of carbon fiber construction. I'm interested to see what this proven team can do.

I'm not criticizing Paul, I'm analysing and gave my opinion (probably I was little sharp, I admit it, will improve :) )

I'm not expert (I have stated it already) hobbyist like others, analysed many, many profiles and rotors and also did own rotor with own aluminium design of extrudat ...I believe I know what I'm telling about ...


PS: about my hobby experience you could find here :
http://www.rotaryforum.com/forum/showthread.php?t=36089
http://www.rotaryforum.com/forum/showthread.php?t=37640
http://www.rotaryforum.com/forum/showthread.php?t=37641
 

Attachments

  • Capture.JPG
    Capture.JPG
    46.7 KB · Views: 4
Last edited:
do you have already some test results (that you could share publicly) for this new blades ?

No, not yet, at least not ready for publication.

- .... Those competence in COMPOSITES BLADES will not help you significantly here ...
Profile is a profile, if extruded or composite, it has the same aerodynamic properties.
This is what we are investigating at the moment.


- probably airfoil you choose/develop with Institute of Aviation in Warsaw will bring some benefits...but many questions to the CONSTRUCTION to the ALUMINIUM BLADE itself (design of extrudat as it is today - I guess you have many challenges with vibration of new blades (already on low speed), compare to the old blades) - did I guess ? I'm not the expert...but from first look it seems that this ALUMINIUM blade will be never dynamically balanced (due to the design of this extrudat itself...)
No, you didn't guess. We are progressing stepwise, the 220mm blades with new internal structure are flying successfully since some time without any issues. The next step are new profiles.

- 220mm of chord - not too much for "light" Tercel ?
No. The TERCEL is designed as 560-600kg MTOW construction.
The 200mm blades were used mainly on 450kg MTOW, or lighter models.

The new blades are designed also for some heavier models, we are working on at the moment.
 
As previously mentioned...yours is the aircraft my wife wants me to buy next (and I'm not against the notion). Can a kit be purchased? Are you working on a 51% approved kit?
 
Hi Chuck - a quick answer before AAT reply.

Mike Bantum is the US agent - the first US Tercel is now with an owner in Missouri ( N226MG ).

A second Tercel ( reserved as N528WM ) is en route ( may have just arrived ? ) to the USA.

HTH
 
Top