My Plane wont fly

[dvdykc]

Anyone can help?

[Nicholas]

well , just by looking at pictures we cant help much

ok , what the problem ? servos all working or nt? motor able to spin in the right direction? or nothing is working at all?

although i do spot some build problems

[dvdykc]

Well I'm a newbie on RC air. I try to hand launch the plane. I apply 50% of thurst and the plane just do sharp slope with the head direct to ground.

I have try to drop the plane from high level, It just fall evenly to gound. Can I said that it achieve COG.

Please let me know what I have don't wrong. thanks

[dvdykc]

All electronic working fine. Fan turn as per normal, servo move accordingly. The wing span is 24" and the length is 34".

Please advise.

[Nicholas]

apply aound 80% for hand launch , cause your plane needs to climb b4 it can fly straight and level , Straight and level will be around 60% if your power to weight ratio is good.

is your CG on the line? looking from your plane design , you would probably have some CG location indicated in the plans?

hand launch : hold it with your hand and spool up the plane with 80% throttle , the one not on the throttle , then toss it upwards , not vertically , like 30-50 degrees so it wouldnt stall if its underpowered , and it wouldnt just float to the ground if its overweight

[dvdykc]

Hi Nicholas,

How about my configuration.

GS Outrunner BL Motor C28-22 1380KV (JetHobby)
DN Li-Polymer 1350mAh/25C 7.4V 2Cell
Align 25A Brushless Motor Electronics
Hitec feather receiver
2 x 8g esky servo.
propeller 8x6

total weight is 280.

The dark line actually is the Carbon rod. which I believe is my CG. Some website mention that if I drop my plane with all equipement and the plane fall evenly, this mean that I have achieve the CG.

Anyway I will try your advise this sat. hope that it will fly.

Thanks for your advise.

[romihensem]

hmmm

how bout thrust angle of yr motor? and yr elevator throw is it enough?

[viper1990]

Everything seems perfectly fine. I've help a friend to do a very simple profile of the F-22 plane just like yours. With a big prop, becareful of handlaunches, big prop = more sucessful hand launches because of the huge static thrust.

Anyway, If your F-22 CG is right on spot, it shouldn't fall evenly towards the ground. It should glide when u release it forward with a push.

Maybe instead of putting your battery in the middle of the fuselage, try shifting it towards the nose to balance the plane right on the CG. If wire isn't long enough, add some dummy weights infront.

If your plane dosen't glide, don't bother flying it yet...., Once you get it flying , it'll be very maneuverable in the air, To decrease sensitivity , attach the push rods to the hole closest to the pivot on the servo.

so good luck!

I've draw a illustration for you to follow.

[dvdykc]

Hi All,

Thanks for all you precious advise. will try them all on this coming sat. Hope my plane can fly.

[jchng]

Hello,

IMHO, once you had sort out the CG of the plane. You may consider flying the plane with a 3 cells lipo instead of a 2 cells lipo. I personally find that it is a dog to fly 2 cells lipo unless if the design really emphasis that. If the design gives you an option for 2 or 3 cells lipo, going with a 3 cells will give you a more spirited flight especially during the NE monsoon. I would prefer to have more power to get me out of trouble when I needed it in that instance as I'm not that experienced to always "think" a few steps ahead of the model while flying

joseph

[skyfool]

my setup

Hi bro, i have built the exact same plane and it flies well enough. You may take my setup as a reference. 1600kv emax brushless motor with 7x6 prop powered by 3 cell batt. I tried with 2 cell and did not have enough punch to fly at all.

[skyfool]

Cg

Looking at your pic again, the only difference is that I have my batt right at the front of the plane. yours is right behind the motor.

[dvdykc]

Any PIC

Hi SkyFool,

Any image of your plane? Need to do comparison. My home to the fly field was not near so very difficult to do test fly.

Thanks in advance.

[skyfool]

decommision

Sorry bro, my plane was decommissioned long ago. I am building planes from parkjet. Soon enough you will be visiting this website for more challenge.

http://www.parkjets.com/

If you were to move your batt to the nose, beware your plane will tilt one side when launching.

[dvdykc]

Everything seems perfectly fine. I've help a friend to do a very simple profile of the F-22 plane just like yours. With a big prop, becareful of handlaunches, big prop = more sucessful hand launches because of the huge static thrust.

Anyway, If your F-22 CG is right on spot, it shouldn't fall evenly towards the ground. It should glide when u release it forward with a push.

Maybe instead of putting your battery in the middle of the fuselage, try shifting it towards the nose to balance the plane right on the CG. If wire isn't long enough, add some dummy weights infront.

If your plane dosen't glide, don't bother flying it yet...., Once you get it flying , it'll be very maneuverable in the air, To decrease sensitivity , attach the push rods to the hole closest to the pivot on the servo.

so good luck!

I've draw a illustration for you to follow.

Hi Viper1990,

Thank for your image guide, I try to launch my plane at first I get the yellow line result. Then I move the battery to next the COG you recommend and now I achieve the green line.

Very happy.

Can't wait to hand launch the plane this sat. Hope it will fly.

Thanks all of you