AutoGyros All about autorotational flight, sport and scale autogyros! User friendly!

Promising 2-bladed pusher design

Reply
Old 02-27-2007, 03:24 PM
  #1
Emilio Cabezas
Thread Starter
 
Join Date: Jun 2006
Location: MAdridMadrid, SPAIN
Posts: 39
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Promising 2-bladed pusher design

As some of you may know, in recent years I´ve had an interest in pusher, Bensen type autogyros. I´ve built and flown several of them quite successfully, fitted with 3-bladed rotors (I had some crashes, too). Full size Bensen types have got two-bladed rotors but, when it comes to RC, three blades do provide more stability than just two (unless special stabilizing devices are employed) and, once the rotor is turning, you can´t tell the difference. Nevertheless, I wanted to try two blades; in September 2005 I achieved success with a tiny 2-bladed, teetering head, Bensen type fuselage model; however, its engine was in a semi-tractor position (forward of the rotor mast, behind the pilot); it wasn´t a true pusher. Perhaps you recall this; I sent a note and photos to this Forum, via Bill Friedlander. A more recent, bigger, true pusher model (.46 engined) also fitted with a teetering rotor, didn´t give the expected results (it actually flew but was unstable).

My most recent model (see photos) is also a true pusher, fitted with a 2-bladed rotor, each blade has its individual hinge (which I thought would be better for stability). It is inspired by a two-seater Bensen type. Last Saturday the model proved to be flyable; several short flights were made against a moderate breeze, all of them hand-launched. The blades are rather heavy, with 0º incidence, no delta-3, so they´re difficult to spin up without a wind. Some trim adjustments and –I hope- slight modifications are yet to be made in order to try to improve the flying characteristics of the model; there is a tendency for the nose to yaw to the right when engine is throttled back.

Here are the specs:
· Rotor diameter: 129 cm (51”)
· Full direct control system (pitch & roll).
· Rudder slightly deflected to the left.
· Weight: 1.450 grs (52 ounces).
· Engine: Enya 25
· Prop: 9x4
· Blade chord: 5.5 cm (2.16 ”)
· Blade airfoil: flat bottomed, 0º incidence.
· Blade thickness: 7mm (0.275”)
· Blade weight: 64 grs (2.28 ounces) - balsa, hardwood L.E., plus some lead.
· Enya engine turns opposite (has its carb turned 90º to the right) so that normal, low pitch propellers can be used. Rotor turns counter-clockwise as seen from above.

Emilio Cabezas
Madrid, Spain



Attached Thumbnails
Click image for larger version

Name:	Om34202.jpg
Views:	21
Size:	120.1 KB
ID:	630996   Click image for larger version

Name:	Mi21842.jpg
Views:	29
Size:	127.0 KB
ID:	630997   Click image for larger version

Name:	Bg93938.jpg
Views:	28
Size:	163.4 KB
ID:	630998   Click image for larger version

Name:	Lf94952.jpg
Views:	21
Size:	40.2 KB
ID:	630999   Click image for larger version

Name:	It98300.jpg
Views:	18
Size:	17.1 KB
ID:	631000  

Click image for larger version

Name:	Wn86283.jpg
Views:	17
Size:	16.4 KB
ID:	631001   Click image for larger version

Name:	Ya56159.jpg
Views:	15
Size:	29.8 KB
ID:	631002  
Emilio Cabezas is offline  
Reply With Quote
Old 02-27-2007, 04:01 PM
  #2
mpoduje
 
Join Date: Mar 2006
Location: Santiago, CHILE
Posts: 2
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

Hi Emilio,

My Name is Miguel Poduje from Chile, i'm very interested to build autogyro... but i had a lot of problems... First i did build a G3P0 electric autogiro.. but crashed in first fly... then i build a autogyro from Arizona builder.. but crashed too in the first fly.

I did build a self design controlline autogyro.. and fly very good.. but in R/C i have all of bad luck...

I did read a lot from you and your autogyros.. and very happy to read you in this forum. Can you send me some advice to build a new autogyro and fly it with out crashing???

Perdone por favor mi muy mal ingles... soy un fanatico de los autogiros y aun no puedo volar uno solo!!!
Muchas Gracias !!!!

Miguel Poduje
FAI CHI-937
Santiago - Chile
Attached Thumbnails
Click image for larger version

Name:	Hf98700.jpg
Views:	23
Size:	55.0 KB
ID:	631016   Click image for larger version

Name:	Vr53217.jpg
Views:	17
Size:	62.1 KB
ID:	631017   Click image for larger version

Name:	Mr39944.jpg
Views:	14
Size:	113.0 KB
ID:	631018   Click image for larger version

Name:	Oh12716.jpg
Views:	18
Size:	45.2 KB
ID:	631019   Click image for larger version

Name:	Lw19563.jpg
Views:	16
Size:	86.9 KB
ID:	631020  

Click image for larger version

Name:	Ne55465.jpg
Views:	16
Size:	114.8 KB
ID:	631021   Click image for larger version

Name:	Qs28739.jpg
Views:	20
Size:	68.5 KB
ID:	631022   Click image for larger version

Name:	Wu71954.jpg
Views:	20
Size:	89.0 KB
ID:	631023   Click image for larger version

Name:	Ut25750.jpg
Views:	21
Size:	28.2 KB
ID:	631024   Click image for larger version

Name:	Gs83751.jpg
Views:	14
Size:	77.2 KB
ID:	631025  

mpoduje is offline  
Reply With Quote
Old 02-27-2007, 11:36 PM
  #3
floridagyro
 
floridagyro's Avatar
 
Join Date: Feb 2002
Location: Wimauma, FL
Posts: 511
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

Hi Miguel,

Your experience is about the same as other autogyro pilots when first starting to fly gyros .

I think the RotorShape Gyro is an excellent beginner gyro. It only takes a couple of hours to build, it's cheap and flies very good. It's a small electric gyro. Here is a link to a review that was written about the RotorShape:

http://www.maxir.logoheli.com/rotorshape_review.htm

Phil
floridagyro is offline  
Reply With Quote
Old 02-28-2007, 04:20 PM
  #4
Emilio Cabezas
Thread Starter
 
Join Date: Jun 2006
Location: MAdridMadrid, SPAIN
Posts: 39
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

Hola Miguel,

I am writing you in Spanish for the advice you´re asking for, hope the other fellows will excuse us. I´m sure the advice Phil gave you is a very good one.
Bueno, es dificil facilitar unas instrucciones completas, en estas pocas l*neas, para construir y volar con exito un autogiro. Seguro que el consejo que te ha dado Phil es bueno. Por mi parte te diré que recomiendo un modelo de autogiro de tipo "trainer" (entrenador), con tres palas, mando directo al rotor (direct control) para "pitch" y "roll" (ó al menos para "roll" como el autogiro de Autogyro Co. of Arizona), fuselaje largo, de manera que las superficies de cola estén fuera del disco del rotor. Supongo que, si has leido sobre m*, conocerás mi diseño "DC Gyro" para un motor .25, que publiqué en la revista americana RC Modeler, Enero de 1998. Te puedo recomendar ese modelo, o alguno similar a él, de los que posteriormente han sido publicados en revistas e incluso alguno comercializado en kit. Un autogiro con motor .25 (4 cc) es conveniente, ya que es lo suficientemente grande para que se vea bien en el aire, sin los inconvenientes del excesivo tamaño y peso (para un principiante) de otros con motores más potentes; también te digo esto último porque yo recomiendo lanzar el modelo a mano (con el debido cuidado para evitar ser alcanzado por el rotor ó la hélice), al menos hasta que se haya aprendido a volar el autogiro, en vez de despegar desde el suelo. Es necesario asegurarse de que el rotor ha adquirido sus revoluciones de vuelo, idealmente enfrentando el modelo a una brisa suave ó moderada, sin correr mucho al principio, dejando que las palas se vayan acelerando gradualmente. (se nota por el ruido particular que hacen y porque se nota que ya no aceleran más, y además se nota la sustentación). Si se lanza sin suficientes rpm, el "crash" está asegurado. Hasta que se adquiera confianza, se puede lanzar el modelo y hacer un corto vuelo a lo largo de la pista, aterrizando al final de ésta, antes de aventurarse a un vuelo en circuito. En fin, si quieres comentar algo más de todo esto, puedes enviarme un mensaje privado a través del foro.

Cordialmente,
Emilio
Emilio Cabezas is offline  
Reply With Quote
Old 02-28-2007, 07:11 PM
  #5
floridagyro
 
floridagyro's Avatar
 
Join Date: Feb 2002
Location: Wimauma, FL
Posts: 511
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

Hi Emilio,

I like your new two blade gyro. I hope that you can improve the performance so that maybe we can all try it.

Now you have to convert the Spanish to English so that we can understand what you told Miguel.

Phil
floridagyro is offline  
Reply With Quote
Old 03-01-2007, 04:20 PM
  #6
Emilio Cabezas
Thread Starter
 
Join Date: Jun 2006
Location: MAdridMadrid, SPAIN
Posts: 39
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

Hi Phil,

Glad to know you liked my two blade gyro. I´ll try my best or longer, more consistent flights.
In short, I just recommended Miguel to build and fly a "trainer type" RC gyro, direct control, three bladed, long fuselage with tail surfaces outside the rotor disc; in case he would go "glow" I recommended a .25 engine for a medium size model. I mentioned my own design DC Gyro , published in RCModeler Jan. 1998 (first flew in 1996) and added that others quite similar have appeared later, even kitted commercially. The rest of the note relates to flight advice: I keenly advocate hand launching in front of a slight breeze for gyro beginners (hence not too large a model) in order to "get the feel" of the spinning rotor and have the model close at the start of the flight; spoke about resisting the temptation of rushing the launch with low rpm and recommended making short flights down the runway before committing to longer and higher ones.

Emilio
Emilio Cabezas is offline  
Reply With Quote
Old 03-02-2007, 12:40 PM
  #7
Gyroguru
 
Join Date: Jul 2003
Location:
Posts: 239
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

Hello Emilio

Can you please post some close up pictures of the gyro specially the head and the servo mounts?

Thanks

Wahid
Gyroguru is offline  
Reply With Quote
Old 03-04-2007, 01:03 PM
  #8
Emilio Cabezas
Thread Starter
 
Join Date: Jun 2006
Location: MAdridMadrid, SPAIN
Posts: 39
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

Wahid,

Here are the photos you wanted. On the second one you can see, from left to right, the rudder, throttle and roll servos. The third one is the pitch servo. Pitch and roll servos are partially covered with painted adhesive tape.

Regards,
Emilio
Attached Thumbnails
Click image for larger version

Name:	Ay73606.jpg
Views:	53
Size:	83.4 KB
ID:	634731   Click image for larger version

Name:	Sn40872.jpg
Views:	31
Size:	56.0 KB
ID:	634732   Click image for larger version

Name:	Ou49506.jpg
Views:	24
Size:	115.7 KB
ID:	634733   Click image for larger version

Name:	At54925.jpg
Views:	24
Size:	47.3 KB
ID:	634734   Click image for larger version

Name:	Fq88496.jpg
Views:	24
Size:	86.6 KB
ID:	634735  

Emilio Cabezas is offline  
Reply With Quote
Old 05-21-2007, 03:59 AM
  #9
TomcatDriver
 
TomcatDriver's Avatar
 
Join Date: Jul 2003
Location: Canberra, AUSTRALIA
Posts: 264
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

Emilio,
This is the Perfect gyro, and exactly what I am looking for,..do you sell kits or plans?,... I would love to build one here in Australia

Thanks
JJ[8D]
TomcatDriver is offline  
Reply With Quote
Old 05-23-2007, 02:14 PM
  #10
Emilio Cabezas
Thread Starter
 
Join Date: Jun 2006
Location: MAdridMadrid, SPAIN
Posts: 39
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

Hello,

Thanks for your note. I don´t sell any kit or plans, at least for the moment. In fact, no plans a such are available yet, I just built the model using a few scketches I made during the design phase. If you have some experience with autogyros, it should not be difficult to build a similar model by using the info provided by the photos and the specifications above. The C. of G. is slightly forward of the rotor axis; if you hang the model from this point, the nose drops by 6º or 7º. As you may have seen in another, recent post of mine, this model is now flying quite well with a teetering head.

Emilio
Emilio Cabezas is offline  
Reply With Quote
Old 08-04-2007, 07:21 AM
  #11
acp
 
Join Date: Aug 2007
Location: , SOUTH AFRICA
Posts: 2
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

test
acp is offline  
Reply With Quote
Old 08-04-2007, 07:28 AM
  #12
acp
 
Join Date: Aug 2007
Location: , SOUTH AFRICA
Posts: 2
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

hi phil

very nice gyro that! i am building a model in the 4.5kg category and was wondering wot the take off run on your 10pound model is without prerotator:wind and windless... a ball park figure is fine, just need to find a suitably lengthed field. it is too big to hand launch.

also interested in the rotorspan of your 10 pounder and what powerplant is sufficient for this weight category. she is almost complete and testing is coming up fast! will try hops at first to try iron out any gremlins...
thanks
andrew
acp is offline  
Reply With Quote
Old 08-10-2007, 07:23 AM
  #13
gyronuts
 
Join Date: May 2003
Location: tadcaster, UNITED KINGDOM
Posts: 81
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

what emilo said , or would appear to have said ,courtesy of google translator was :
"Good, it is difficult to facilitate complete instructions, in these few lines, to construct and to fly an autogyro successfully. Certainly the advice who has given Phil you is good. As for me I will say to you that I recommend a model of autogyro of type " trainer" (trainer), with three shovels, direct control to the rotor (direct control) for " pitch" and " roll" (or at least for " roll" like the autogyro of Autogyro Co. of Arizona), long fuselage, so that the tail surfaces are outside the disc of the rotor. I suppose that, if there are leido on me, you will know my design " DC Gyro" for a motor,25, that I published in American magazine RC Modeler, January of 1998. You I can recommend that model, or some similar to him, of whom later they have been published in magazines and even some commercialized in kit. An autogyro with motor,25 (4 cc) is advisable, since it is sufficiently great so that it is seen well in the air, without the disadvantages of the excessive size and weight (for a nascent one) of others with more powerful motors; also I say this last one to you because I recommend to send the model by hand (with the had one taken care of to avoid to be reached about the rotor or the helix), at least until has learned myself to fly the autogyro, instead of to take off from the ground. Is necessary to make sure that ideally the rotor has acquired its revolutions of flight, facing the model a smooth or moderate breeze, without running much at the outset, leaving shovels them they are accelerated gradually. (note by the particular noise that does and because note that no longer more accelerate, and in addition notices the sustenation). If it is sent without sufficient rpm, " crash" it is assured. Until confidence is acquired, the model can be sent and to do a short flight throughout the track, landing at the end of this one, before venturing itself to a flight in circuit. In short, if you want to comment something more of all this, you can send a message to me deprived through forum. "
Bill

gyronuts is offline  
Reply With Quote
Old 09-27-2007, 04:42 PM
  #14
gyronuts
 
Join Date: May 2003
Location: tadcaster, UNITED KINGDOM
Posts: 81
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Promising 2-bladed pusher design

Emilio,
Any more progress with your gyro. It looks great and similar to the full size MT03/ELA07/VPM. Any plans to produce a plan?
very interested in your gyro. Tell us more .Bill
gyronuts is offline  
Reply With Quote
Reply


Thread Tools
Search this Thread
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 01:29 PM.