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Old Nov 25, 2012, 07:25 AM
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Canada, ON, Burlington
Joined Jan 2009
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Quote:
Originally Posted by p901P901 View Post
Anybody noticed how flimsy the flight controls are when separated from the tape hinges?

What is the recommended servos? Will need ailerons, flaps, elevators, and rudder.
They must have used good tape on mine as they are holding fine. I keep a close eye on them though!

I use HXT900 in many of my planes. Mine came with some emax 9g servos and I have had to replace the elevator servos with HXT900 as the emax were acting up. The other emax servos are still working but they will likely be replaced with more HXT900 due to their sloppy,noisy operation. Remember, my plane is operated on 6S and if you want a higher powered ship, you might want to go to 2.5kg servos. The new Turnigy 9018 are very nice servos with metal gears and 2.5kg torque. I took one of mine apart and it is very well made.
Cheers
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Old Nov 25, 2012, 08:38 AM
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United States, NY, New York
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For any of the guys interested in budget but decent servos and have an edge over hxt-900. Go for the turnigy 9018 MG 2.5kg/13g/0.10 sec
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Old Nov 25, 2012, 08:39 AM
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Quote:
Originally Posted by 4stripes View Post
They must have used good tape on mine as they are holding fine. I keep a close eye on them though!

I use HXT900 in many of my planes. Mine came with some emax 9g servos and I have had to replace the elevator servos with HXT900 as the emax were acting up. The other emax servos are still working but they will likely be replaced with more HXT900 due to their sloppy,noisy operation. Remember, my plane is operated on 6S and if you want a higher powered ship, you might want to go to 2.5kg servos. The new Turnigy 9018 are very nice servos with metal gears and 2.5kg torque. I took one of mine apart and it is very well made.
Cheers
Sorry buddy for the repeat!!! we were thinking in the same line and at the same time.
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Old Nov 25, 2012, 05:45 PM
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USA, CA, Aromas
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Quote:
Originally Posted by p901P901 View Post
Anybody noticed how flimsy the flight controls are when separated from the tape hinges? I decided to remove about a half inch from the leading edge and laminate 1/6" balsa to the surfaces. Removing 1/2" from the leading edge would duplicate the original thickness.with the laminates.
The wings are epoxy resined with 2oz cloth and reinforced with 1/8" x 3/8" x 32" carbon strips. Wings are super stiff. Fuselage is coated with .75oz cloth and a 1 to 1 mixture of wood glue and water. This is allot of work and wonder if I should have taken the liquid skin rout on the fuselage.
Going with a midi fan with a Arc 36-75-1 (1680KV) on 8 - 10 cells. What is the recommended servos? Will need ailerons, flaps, elevators, and rudder.
I liquid sheeted my control surfaces after cutting them off so they came out very stiff and rigid

the arc 3675-1 is a 6s motor using a wemo and can go to 8s for high performance expect to see 100+amps on 8s and 8-9lbs thrust with good batteries. this would be a good setup provided you can get your cg with 8s
I could not get a good cg on 8s, mine cg's good on 10s

for servo's I used Het digitals dont remember the model but they fit perfect in the servo pockets and are 2.5kg torq metal gear with ball bearing. I used those on every surface except elevator for those I am using Turnigy 380max metal gear, ball bearing analogs with 50in oz of torq. all servos running on regulated 6vdc via 7.5amp ubec
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Old Dec 04, 2012, 03:42 PM
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Yeah, here it is!

L-39 Flight at Dusk (11 min 3 sec)
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Old Dec 04, 2012, 04:27 PM
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nice vid jandro
I always like your vids.........great job....great music!.......makes me want to go fly mine lol!!
now take your euro fighter 8s setup and put it in the L39 you will like it soo much better

John
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Old Dec 04, 2012, 05:03 PM
Flying Hazard
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Hehe, good try, but that setup will go on a new EF anytime soon
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Old Dec 04, 2012, 05:14 PM
3DHOG
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ok that sounds good, was just sayin the L39 is a bit sluggish on 6s
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Old Dec 04, 2012, 05:27 PM
Another one on the way...
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You were having fun there, weren't you? Beautiful flight, gorgeous landing! Making slow progress on mine...
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Old Dec 05, 2012, 04:22 AM
Fredrik Pousard, Sweden
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Gothenburg, Sweden
Joined Oct 2009
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Originally Posted by SU-4ever View Post
Yeah, here it is!
Nice! Great to see some slow flying for a change.. The stall around 9:25 did looked really gentle I must say. Does this bird have any bad flying habits?
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Old Dec 05, 2012, 04:27 AM
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United States, NY, New York
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su,
what setup do you have on the L-39 ?
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Old Dec 05, 2012, 08:12 AM
Flying Hazard
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Torchy everything is pretty much stock plane with HTG upgraded landing gear which actually is pretty poor and ill finished and bends too. I'm using SK3 Fandrive for 90mm EDF from HK with a Freewing Eurofighter's stock fan replacing the spinner for a metallic spare I had left of a crashed wemotec midi pro. I'm using TGY 85A ESC with built-in BEC and Haiyin 6s 5000mAh batts in the 25-35C and 30-40 C rating classes. Assan radio equipment and Corona 939 MG servos all around with a rudder mod included but lacking flaps and nose wheel steering. No gyros either. Retracts are Ping Zheng standard model with metal trunion. That is enough power for unlimited vertical climbouts and some speed but it's definitely not the setup for you if you want this to become ballistic. on the other hand I'm doing 4 minutes flight at 1900mAh consumed so I could easily extend that to 8 and 9 min. flight! Now that's a nice change over 3D jets (3min) and great considering I want this plane for FPV PURPOSES.

Quote:
Originally Posted by ysolomon View Post
You were having fun there, weren't you? Beautiful flight, gorgeous landing!
Hehe, thanks, always trying!

Quote:
Originally Posted by fege View Post
Nice! Great to see some slow flying for a change.. The stall around 9:25 did looked really gentle I must say. Does this bird have any bad flying habits?
Yes and no... depends on your point of view about bad habits...
This is a pretty easy to fly jet, with a very easy take off compared to fighters like Sukhoi and Eurofighter, but it's meant to flight straight and little more, it doesn't like to be pushed out of its flight envelope.
For example, you reach lift off speed before proper aerodynamic control is achieved so if you take off too early the plane can present some serious wing rocking. See the knife edge after take off on my video? Well, that was not on purpose...

About stalls, when flying slow I've found that I DO NOT HAVE enough pitch authority to put the plane into a stall. Instead, it adopts a slow, pitched down glide path that you cannot recover unless gathering speed but the wings seem stable.

This bird has no thrust vectoring so you don't have means of low speed control. This means if you stall on landing approach the plane simply wing rocks, and maybe you don't have enough rudder / aileron to compensate, so until I get more confidence my landings are a bit hot.

Then again, if flying too slow it appears difficult to maintain a nose-high attitude and have enough stick travel for a decent response, and that I don't like. Maybe I'm too used to supermaneuverable airframes, my bad.

Another thing I found is it pitches up when adding throttle, I'm still trimming the plane for level flight but in the end (After all trim that can be done) I think I will use a low-gain pitch gyro for the best compensation and precision at different speed regimes and sudden acceleration changes, which couldn't be completely resolved on a transmitter THR-ELE program mix since response varies with speed.

Other the that, the plane is an angel to fly.

Then again, that is my opinion, let's see what the others say.
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Last edited by SU-4ever; Dec 05, 2012 at 08:22 AM.
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Old Dec 05, 2012, 08:17 AM
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Su.
Thanks. Which sk3 do you have 1900 or 1600 kv?
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Old Dec 05, 2012, 01:32 PM
Flying Hazard
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Spain
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1900Kv
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Old Dec 05, 2012, 03:54 PM
3DHOG
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USA, CA, Aromas
Joined Sep 2010
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Jandro
a couple of things for you to try out
your pitch up when under power is cg you are still nose heavy, move the batt back a little at a time untill that goes away also add some crow to your ailerons for take off and landings, start at 2mm. this will decrease the tip stalling and these two things together will allow for even slower more stable performance
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