F4U Black Corsair

[viggen]

just needs one more coat of paint then varnish...i love the look of this plane.cant wait to get it in the air..just waiting on my tacon motor to arive

 

[viggen]

please can i have some help..i flow the plane for the first time today...and it needs about 5-6 degrees up elevator for it to fly straight...all the plane want to do is go up.could it be because i put the balsa spar on the bottom of the plane instead of the top?my setup
tacon bigfoot 10 110kv
nano 2200 4s 45-75c
10x7 apc
total weight 1320g

apart from this little problem.this is my new favorite plane...it can fly crazy slow and landings are so easy.with no landing gear and also its fast with a bigfoot 10

thanks

 

[jayz 84]

If you a pulling up at high throttle then first you might wanna check into some down thrust. And check you cg again, you might be on the tail heavy side. But check down thrust first. Thats a big thing when it comes to larger props and alot more power

 

[viggen]

it doesnt mater what speed im doing.even less than half throttle.it using a lot of up elevator..to keep level
i can try moving the battery forward a few mm.but i thought that i would be nose heavy if im using a lot of up elevator...or am i wrong

my cg is in the middle of the wing spar.thats 3in from the leading edge,with the plane turned over

 

[jayz 84]

Ahhh ok i miss read it. I was at work when you pm me for help. I thought i read the plane was pulling up ( sorry) in that case your nose heavy try moving the battery back alittle bit at a time to see if this corrects the issue. If not then you have wing incidence issue

 

[viggen]

thanks jay.i will try moving the battery back.soon as it stops raining.
what makes this plane able to fly so slow and stable and making landing so easy?
is it wing thickness or just the wing shape?

 

[viggen]

ive moved the battery back as far as possible.about 20mm.but didnt make any differance.grrr

 

[jayz 84]

Stick your plane on a table and give use a few nice level side view pictures if you can. So i can check your motor angle and wing incidence before we do anymore guessing. And take a pic to of where your elevator position is during level flight

 

[Topper60]

very nice airplane good job

 

[viggen]

here we are.battery is in flying position,elevator up to fly level at half throttle.in pic 4 could it be the 5mm balsa spar getting in the way.i think it was ment to be on the top not the bottom...paint got a bit wet.thanks

 

[jayz 84]

VIGGEN...... OK looking at your pix and reading back i was right the first time. Right now your elevator is pointing for nose down (not up elevator) to keep level flight so it is pulling up on you. So first try moving the battery fwd just because you said it pulls up at any speed. Then add a thin washer behind the top two motor mounts for a hair of down thrust. Dont go crazy moving the battery fwd at first just alittle at a time. Start from where it was on your maiden. Go with 1cm fwd of that to start

 

[viggen]

ok thanks i will try moving it more forward..i think i can move the battery upto 30mm.i also have 1mm washer in the top left corner to help with torque roll.and it did work.i will try 2x1mm washer top left and 1 top right.thanks again.its a great plane...its got tons of drag.you can hear it when going flat out.lol

 

[viggen]

this is with the battery all the way back...no idea why i thought the plane could fly like this.lol

battery all the way forward 30mm..now by looking at the pix this should solve the problem,i cant wait to try tomorrow morning.if not then i will add washers to top mounts

 

[jayz 84]

Move it back about 10-15 mm that pretty nose heavy now. You want it just slightly nose down. But yeah the top pic you would have fun flying that if you can

 

[viggen]

for mained battery was in the middle.elevator level and it just went straight up....wasnt fun at all.

thanks

 

[viggen]

well i moved battery all the way to the front.it helped a small amount.but still needed a lot of up elevator trim....i then lost control of it.not sure what happened..and it snaped the cowling clean off,infront of the wings,easy repair,now has some down thrust from the crash,i only need 1 click of up elevator trim from level.and it seems a lot more stable...

thanks for all your help john

 

[Troutbum24]

Sorry guys, Im kind of confused on which plans to use. Im trying to print on a plotter but realised the version i printed looks different and the fuselage does not have wing slots cut out. Can someone point me out the link to the full plan..? Thanks
blaine

 

[Alp]

Then add a thin washer behind the top two motor mounts for a hair of down thrust.

Viggen, indeed jayz says true. I see, your motor stands a little up trust or horizontal. You should do a little (2-3 degree) down trust .

 

[Troutbum24]

Sorry guys, Im kind of confused on which plans to use. Im trying to print on a plotter but realised the version i printed looks different and the fuselage does not have wing slots cut out. Can someone point me out the link to the full plan..? Thanks
blaine

Nevermind I think I found my answer in post 103. Cant wait to start this build!!!!

 

[Alp]

Nevermind I think I found my answer in post 103. Cant wait to start this build!!!!

You have to use latest plan..
ALP-F4U CORSAIR v1.pdf