Thread Tools
Feb 16, 2017, 08:31 PM
Plank addicted
Marcos Quito's Avatar
Dear Srs. , this is just to inform that we' re waiting the good wheather to come in order to test fly the glider.

In the region I live the slope needs only one direction wind, the cold South wind.

But now it s raining cats and dogs, and the wind is north, useless.

I don' t consider, yet, to put a motor on the nose.
Sign up now
to remove ads between posts
Apr 02, 2017, 03:41 PM
Plank addicted
Marcos Quito's Avatar
Finally first fly !!

Plank 2.4m foam - slope at Cristinho, Sao Carlos, SP, Brazil (1 min 0 sec)


Results : If I was alone I would be very satisfied with overall results :

CoG great, Profile perfect no need big up elevator.
Ailerons small, little response.

But,..... there were a few other fliers together with spirit2m, Fling1.2m, ... and all they were very much higher than my plank in the air.,..

Upset, because its light weight, big area , and still flying like a block of brick.
Apr 02, 2017, 03:46 PM
Plank addicted
Marcos Quito's Avatar
Follow photo
Apr 02, 2017, 04:56 PM
less is more
Knoll53's Avatar
Quote:
Originally Posted by Marcos Quito
But,..... there were a few other fliers together with spirit2m, Fling1.2m, ... and all they were very much higher than my plank in the air.,..
I know EXACTLY what you are talking about. I had the same experience with my super light SW-2 when out at the slopes and a 2m EPP conventional RES plane out flew me. It is true that you don't need a tail to fly, but it does allow you maximize the lift of the main wing.
Apr 02, 2017, 06:50 PM
Plank addicted
Marcos Quito's Avatar
Yep, Mr Knoll... I really like the simplicity of planks.
But now my airfield has very weak lift, thus I should consider a conventional airframe.

(I think to do this stupid thing : put an stabilizer in this wing - conventional fuselage. I can put some camber in the airfoil, and it's ready !)
Apr 02, 2017, 07:18 PM
Herk
HerkS's Avatar
Marcos - Do you think that the model may be somewhat nose heavy?
Apr 02, 2017, 09:37 PM
Registered User
czorzella's Avatar
Quote:
Originally Posted by herks
marcos - do you think that the model may be somewhat nose heavy?


+1.
Apr 03, 2017, 09:59 AM
Plank addicted
Marcos Quito's Avatar
Quote:
Originally Posted by czorzella
+1.
2x nose heavy ???
C´mon !!
What am I doing ?

My arguments :
#1 - Ok, I agree, it was first flight, of course I´ve pushed a little the CoG, for safety....
#2 - Trimm after landing was 2mm positive pitching. For a hand made "foam", 350mm chord wing, that´s nothing !!!
#3 - Any thermal bubble it goes nose up at 45 degrees, like crazy. I will, I promise, try to bring back the CoG a little bit

I´m downloading one more video, with more close up flights and you give the last judgement please.

Follow video :

Plank 2,4m RC glider 2nd video (1 min 12 sec)
Apr 03, 2017, 07:29 PM
Herk
HerkS's Avatar
Regarding CG, I understand that the span is 2400mm and the chord is 350mm.

if this was my flying wing I would begin test flying with the balance point 70mm from the leading edge of the wing. Then after flying it for a while I would try to move it back, but not further than 80mm. It would interesting to learn where you have your model now balanced. This is based on calculations that I have used for my models.
Apr 05, 2017, 10:17 AM
Plank addicted
Marcos Quito's Avatar
Quote:
Originally Posted by HerkS
Regarding CG, I understand that the span is 2400mm and the chord is 350mm.

if this was my flying wing I would begin test flying with the balance point 70mm from the leading edge of the wing. Then after flying it for a while I would try to move it back, but not further than 80mm. It would interesting to learn where you have your model now balanced. This is based on calculations that I have used for my models.
Hello HerkS,
Yes, that´s precisely my goal 70mm. I´ve started with 65mm, but now it´s on 70mm - which is still safe.
I think to go further, but as I´ve mentioned, at thermals it goes nose up easely.


Thread Tools