CY MODELS La-7//Evolution 160 radial
11-02-2017, 09:36 PM
#377
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As I say yesterday, here the link for the maiden flight, and the second flight. Sorry, but my camera setup was wrong, and the sun make the job a bit difficult...
I am happy with the La-7, it seems as a good model. I see that the elevator and aileron throws are to high, it mus be reducted for scale flying. I do not have test the full flaps seting on approach, that's why the Lavochkine comes with to hight speed on landing. I test this on next flight.
The flight characteristics are good, looping comes with no difficulties, inverted flight with an little amount reverse elevator, and barrel roll is a must. The take off must be accompanied with a little down elevator in the first meters since the tail is coming up, and let it roll, stay on line with the rudder, hold full gas, and you will see it is airborne!
Th CG seems to be good, i try to make a little correction on it for the next flight. In the landing configuration, with this CG, you have full control on the elevator, and you can manage it easy for the final, here is no stall problem. The ground handling is good, with no nose over problems.
The next job for me is to make the cockpit, and install the pilot on it.
The Saito FG-84 R3 will be modified next month one more time, i am not 100% happy with the settings on middle throttle. Will see what i can make. In flight, the Saito and Keleo exhaust gives a good sound, it's a pleasure.
Jimmy, have you planed your maiden ?
I am happy with the La-7, it seems as a good model. I see that the elevator and aileron throws are to high, it mus be reducted for scale flying. I do not have test the full flaps seting on approach, that's why the Lavochkine comes with to hight speed on landing. I test this on next flight.
The flight characteristics are good, looping comes with no difficulties, inverted flight with an little amount reverse elevator, and barrel roll is a must. The take off must be accompanied with a little down elevator in the first meters since the tail is coming up, and let it roll, stay on line with the rudder, hold full gas, and you will see it is airborne!
Th CG seems to be good, i try to make a little correction on it for the next flight. In the landing configuration, with this CG, you have full control on the elevator, and you can manage it easy for the final, here is no stall problem. The ground handling is good, with no nose over problems.
The next job for me is to make the cockpit, and install the pilot on it.
The Saito FG-84 R3 will be modified next month one more time, i am not 100% happy with the settings on middle throttle. Will see what i can make. In flight, the Saito and Keleo exhaust gives a good sound, it's a pleasure.
Jimmy, have you planed your maiden ?
11-03-2017, 01:01 AM
#378
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Hi Warbird, I like your setup. Congratulation for your maiden. I am closely following your construction from Jimmy and you since a few time. Both of you are making so great job !
I am working on the same kit an plan to fly with an old radial engine Seidel 70 cc that stayed in exposition since too much time. Not sure if it will be powerful enough but want to try at least.
I've also modified the gear fixing, taking inspiration from the David Andersen design, making a 3D CAD modeling and CNC cut of new ribs and gear support. Gear is now quite close to scale. I have now to reinforce the fuselage in the gear retracted area.
I am working on the same kit an plan to fly with an old radial engine Seidel 70 cc that stayed in exposition since too much time. Not sure if it will be powerful enough but want to try at least.
I've also modified the gear fixing, taking inspiration from the David Andersen design, making a 3D CAD modeling and CNC cut of new ribs and gear support. Gear is now quite close to scale. I have now to reinforce the fuselage in the gear retracted area.
11-03-2017, 01:08 AM
#379
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Total weight dry is 12,2 kg but need approx 1,5 kg in front for balancing. Means a little less than 14 kg finished, but without scale details. I have to take care of power/weight ratio...
Which propeller do you have with your saito and which rpm ?
Which propeller do you have with your saito and which rpm ?
11-03-2017, 03:58 AM
#380
As I say yesterday, here the link for the maiden flight, and the second flight. Sorry, but my camera setup was wrong, and the sun make the job a bit difficult...
https://www.youtube.com/watch?v=kxs2X1s_XXY
I am happy with the La-7, it seems as a good model. I see that the elevator and aileron throws are to high, it mus be reducted for scale flying. I do not have test the full flaps seting on approach, that's why the Lavochkine comes with to hight speed on landing. I test this on next flight.
The flight characteristics are good, looping comes with no difficulties, inverted flight with an little amount reverse elevator, and barrel roll is a must. The take off must be accompanied with a little down elevator in the first meters since the tail is coming up, and let it roll, stay on line with the rudder, hold full gas, and you will see it is airborne!
Th CG seems to be good, i try to make a little correction on it for the next flight. In the landing configuration, with this CG, you have full control on the elevator, and you can manage it easy for the final, here is no stall problem. The ground handling is good, with no nose over problems.
The next job for me is to make the cockpit, and install the pilot on it.
The Saito FG-84 R3 will be modified next month one more time, i am not 100% happy with the settings on middle throttle. Will see what i can make. In flight, the Saito and Keleo exhaust gives a good sound, it's a pleasure.
Jimmy, have you planed your maiden ?
https://www.youtube.com/watch?v=kxs2X1s_XXY
I am happy with the La-7, it seems as a good model. I see that the elevator and aileron throws are to high, it mus be reducted for scale flying. I do not have test the full flaps seting on approach, that's why the Lavochkine comes with to hight speed on landing. I test this on next flight.
The flight characteristics are good, looping comes with no difficulties, inverted flight with an little amount reverse elevator, and barrel roll is a must. The take off must be accompanied with a little down elevator in the first meters since the tail is coming up, and let it roll, stay on line with the rudder, hold full gas, and you will see it is airborne!
Th CG seems to be good, i try to make a little correction on it for the next flight. In the landing configuration, with this CG, you have full control on the elevator, and you can manage it easy for the final, here is no stall problem. The ground handling is good, with no nose over problems.
The next job for me is to make the cockpit, and install the pilot on it.
The Saito FG-84 R3 will be modified next month one more time, i am not 100% happy with the settings on middle throttle. Will see what i can make. In flight, the Saito and Keleo exhaust gives a good sound, it's a pleasure.
Jimmy, have you planed your maiden ?
11-03-2017, 09:19 AM
#384
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You can save weight with Kavan superlight Wheels, weighting 100 gr for a 150mm Wheel. If you put the elevator servo in front of CG, and do not take a retractable rear gear, and you implant all the rest in front of CG, also you have a chance to obtain a light Lavotchkine.
Actually i think that the Seidel 77 will be to underpower for this size of plane, specially for a warbird, because if you would like fly scale, the plane must be able to make maneuvers in the vertical plane! This engine would be good on a 2.1m warbird, as the topflite FW-190.
My Saito FG-84 swing a Mejzlik 24x12 2 blades at 6100 rpm.
Last edited by warbird04; 11-03-2017 at 09:23 AM.
11-03-2017, 09:21 AM
#385
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Hi Warbird, I like your setup. Congratulation for your maiden. I am closely following your construction from Jimmy and you since a few time. Both of you are making so great job !
I am working on the same kit an plan to fly with an old radial engine Seidel 70 cc that stayed in exposition since too much time. Not sure if it will be powerful enough but want to try at least.
I've also modified the gear fixing, taking inspiration from the David Andersen design, making a 3D CAD modeling and CNC cut of new ribs and gear support. Gear is now quite close to scale. I have now to reinforce the fuselage in the gear retracted area.
I am working on the same kit an plan to fly with an old radial engine Seidel 70 cc that stayed in exposition since too much time. Not sure if it will be powerful enough but want to try at least.
I've also modified the gear fixing, taking inspiration from the David Andersen design, making a 3D CAD modeling and CNC cut of new ribs and gear support. Gear is now quite close to scale. I have now to reinforce the fuselage in the gear retracted area.
11-03-2017, 09:28 AM
#386
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It sounds good, nice engine, and with 7 cylinders is a eye stopper !
11-03-2017, 07:32 PM
#387
the break in for this engine is 2000 rpm five minutes at a time until a full tank is used....in my case that’s 50 oz. That will take arbor two hours to accomplish. I have only gotten to run the engine for 15 minutes because the ignition failed during the third run. I have sent the engine to Horizon for repair and will update you when I get it back on the airframe
11-04-2017, 06:05 AM
#389
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Ok, you're probably right. Just ended some more trials with the Seidel and it swing 26x8 Menz 2 blades @ 4800 rpm. I have to try a 24x10.
I will post some more pictures later on.
Setup is with retractable tailwheel Robart (with lado actuator), electron retract ER40 for main gear, all servos savox, emcotec dual bat, redundancy bus frsky with 2 receivers.
Which torque do you have in your miniservos on the elevator ? I have actually selected SA-1258TG 12kg which are probably oversized.
I will look to implant rudder servo in front of CG and all batteries in the cowl (not lipo).
I will post some more pictures later on.
Setup is with retractable tailwheel Robart (with lado actuator), electron retract ER40 for main gear, all servos savox, emcotec dual bat, redundancy bus frsky with 2 receivers.
Which torque do you have in your miniservos on the elevator ? I have actually selected SA-1258TG 12kg which are probably oversized.
I will look to implant rudder servo in front of CG and all batteries in the cowl (not lipo).
11-05-2017, 01:16 PM
#390
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12 Kg for each elevator is oversized. But today we have choise on many different brand, and prices.
Take care at first of the elevator servos weight... each gramm is to gain. Same thing for the rear retract, better a mechanical retract with the servo in front of the CG, as a electric! On the La-7, each gramm on the elevator, is to compensate with 3.5 gramm in the nose...
I have on each elevator Graupner DES 678 BB MG, with 7.5 kg torque @ 6.0v, and they weight 28 gr each.
Take care at first of the elevator servos weight... each gramm is to gain. Same thing for the rear retract, better a mechanical retract with the servo in front of the CG, as a electric! On the La-7, each gramm on the elevator, is to compensate with 3.5 gramm in the nose...
I have on each elevator Graupner DES 678 BB MG, with 7.5 kg torque @ 6.0v, and they weight 28 gr each.
11-09-2017, 12:48 AM
#391
12 Kg for each elevator is oversized. But today we have choise on many different brand, and prices.
Take care at first of the elevator servos weight... each gramm is to gain. Same thing for the rear retract, better a mechanical retract with the servo in front of the CG, as a electric! On the La-7, each gramm on the elevator, is to compensate with 3.5 gramm in the nose...
I have on each elevator Graupner DES 678 BB MG, with 7.5 kg torque @ 6.0v, and they weight 28 gr each.
Take care at first of the elevator servos weight... each gramm is to gain. Same thing for the rear retract, better a mechanical retract with the servo in front of the CG, as a electric! On the La-7, each gramm on the elevator, is to compensate with 3.5 gramm in the nose...
I have on each elevator Graupner DES 678 BB MG, with 7.5 kg torque @ 6.0v, and they weight 28 gr each.
