this means i will have to wait for some more time till i get the smaller prop .

While test gliding do i have to simply allow the plane to glide by its own or operate the elevator.

Vicky

Other wise, handle throttle carefully and avoid full throttle. Or cut the prop to a small size and balance it,

Sir how to adjust the CG. My plane seems nose heavy and I cannot move the battery as its slot is fixed.
And once again the same question, while test gliding do i have to simply allow the plane to glide by its own or operate the elevator.

Quote from: Ashta on February 23, 2010, 02:59:33 PM
Let me estimate ur model wt.
Motor+prop 58
Esc   40
RCVR 10
Servo 15
Bat 100
Total 223.00 Grams
Model wt = say max 200
So total 423.00 say 450 grams.

Got actual weight of the model from a near by shop
it weighs 290 gms  (including every thing)

Quote from: vicky on February 26, 2010, 08:14:17 PM
Got actual weight of the model from a near by shop
it weighs 290 gms  (including every thing)

That means that ur model wt w/o any gear is only 70 grams??? or ur battery is not 100 grams. some thing is fishy. or are u telling me the total wt w/o battery? am i missing some thing?

Quote from: Ashta on February 27, 2010, 10:27:11 AM
That means that ur model wt w/o any gear is only 70 grams??? or ur battery is not 100 grams. some thing is fishy. or are u telling me the total wt w/o battery? am i missing some thing?

I have included every thing even the prop saver, the 9X4.7 prop and the wing. The only thing possible is digital balance of the shop is faulty . or may be you have taken wrong weights for calculation. I will cross check it with some other shop.

Hi Astha

Since we are talking about weights here..Is it possible to make a 32 inch profile foamy from biofoam weighing only 100 gms(without the lipo,servos,reciever,esc and motor+prop) ? You have any similar model you could weigh and check. I have kept that weight as a target for my foamy...any building tips for achieving that???

Regards
Ankur

this is the lightest that i have been able to make with 32 inch ws
238n grams and 276 grams with 450mah, 3cell


"The plan is from Slowfly. Made out of 8mm EPP with carbon rods.
WS=32inch,9gms servox3, 9gms Esc,GWS4p,Bw1300x 6050prop, 450mah Thunderpower cell"

Quote from: ankurkaul17 on February 27, 2010, 01:11:26 PM
Hi Astha

Since we are talking about weights here..Is it possible to make a 32 inch profile foamy from biofoam weighing only 100 gms(without the lipo,servos,reciever,esc and motor+prop) ? You have any similar model you could weigh and check. I have kept that weight as a target for my foamy...any building tips for achieving that???

Regards
Ankur

Here is the video clip of maiden flight. The plane flew well but it was not stable which i could not understand . Can anyone tell me the symptom-problem relationship.

maiden flight really

i think u have a CG problem !

Hi Vicky

Congrats on your maiden ...barely escaped the crash  

And yes as sahil said it looks like you have a CG problem. Looking at the video I guess the plane is nose heavy and as the plane's nose drops down you apply elevator to compensate..try moving the CG back. And do not use too much throws on the elevator.

Overall a very good flight

Edit : On again viewing your video now i feel the plane may be tail heavy. try fiddling with CG. get the CG to around 30-33% of Chord. If the nose is rising automatically then you have to move CG forward otherwise the opposite way.

Regards
Ankur

Quote from: sahilkit on February 27, 2010, 09:43:12 PM
i think u have a CG problem !

May be u are right . Initially I had CG problem but I balanced it by putting some clay on the tail end. Tomorrow i am planning to fly it again after adjusting the CG this time I will closely observe what exactly is the problem.

Quote from: ankurkaul17 on February 27, 2010, 09:50:27 PM
Edit : On again viewing your video now i feel the plane may be tail heavy. try fiddling with CG. get the CG to around 30-33% of Chord. If the nose is rising automatically then you have to move CG forward otherwise the opposite way.

Regards
Ankur

Ankur, I doubt the problem my be with the thrust vectoring also

Quote from: vicky on February 27, 2010, 10:02:49 PM
Ankur, I doubt the problem my be with the thrust vectoring also

Hi Vicky

I am not getting you. I never mentioned thrust vectoring...i dont think you are using thrust vectoring. What i mean to say is that if your planes noses down then it is nose heavy and you need to move the CG back. if you plane noses up the your plane is tail heavy and CG needs to be shifted forward.

If the plane is nose heavy it will dive. if the plane is tail heavy then its nose will rise and eventually it will enter into stall..then the nose will drop down and it will start loosing altitude..the potential energy which it is loosing(ie height) will be converted into velocity (Kinetic energy). as the sped increases lift increases and the plane will start nosing up and this process will repeat. i think that is what is happening here. I COULD BE WRONG ALSO. The next time you fly observe the flying pattern carefully.

sorry for the poor drawing..i was in hurry.


Regards

I know what u r talking about! Apart from the CG i just raised a doubt of motor angle because when i checked my model it was perfectly balanced at 33% from LE.

Quote from: vicky on February 28, 2010, 10:38:34 AM
I know what u r talking about! Apart from the CG i just raised a doubt of motor angle because ...

Dear Vicky

Thrust vectoring is totally different concept where in the thrust from the engine is deliberately changed to provide greater maneuverability. In real planes this is achieved by deflecting the nozzle whereas in RC planes it is achieved by changing the axis of the motor with a servo. That is the reason i got confused.

How have you mounted your motor. 2 degrees down and 2 degrees right?

Well I dont know how much is the angle but i am aware of the 2 degs down and 2 deg right concept.
BTW how to measure the angle.

Today I flew it once again after some adjustments in the CG and the rudder and it was so stable that I found it a better model than "slowstick".
I did some loops also. Sorry I could not get the video as I was alone at the field. 
It is such a forgiving model that, no matter how big mistake you make it allows you to correct it .
I would recommend this model to every beginner .

Plan and detailed build log is available at
http://www.rcgroups.com/forums/showthread.php?s=41628bb6631af1730bd32e47df27755f&t=1040899

hello sir
what r meterials used in making this plane





 

Dinil, I used 5 mm biofoam sheet for fuselage and the wings and thermocole for monoblock. For push rods I have used the broom sticks . Please go through the attached pictures

Quote from: vicky on February 26, 2010, 06:52:53 PM
Sir how to adjust the CG. My plane seems nose heavy and I cannot move the battery as its slot is fixed.
And once again the same question, while test gliding do i have to simply allow the plane to glide by its own or operate the elevator.

dear vicky,
Excellent and congrats for the successfull maiden. It is flying verywell.
best regards
ashta

Thanks Ashta

Hi all,

Today I replaced the wing with Kfm3 Wing with ailerons . Pictures attached below

Regards
Vicky

Video of aileron functioning . Planning for test flight tomorrow.




Regards
Vicky