Excellent and a great P47. Vanessa gives excellent CG and as a RC pilot that's what you should have. Like the big IRON you should use trim for attitude . CG is designed to be in front of Center of Lift thus when the windmill stops turning the nose drops and the designed glide speed is set up . Pilots used to say, :All it takes to fly is airspeed and money" but without you're CG right, you are dead on the money.
Hello Don, I have a question about zeroing the incidence. If a plane have a built in +1 Deg of incidence, which is understood that the plane will fly level at that degree on incidence, is balancing the model at 0 Deg incidence correct since it would not be straight and level in the air. Why not balance the aircraft at +1 Deg if upright or -1 Deg if inverted? I am nor arguing the issue, just asking to learn the system, since I intend to build one and have to learn how to use it correctly. Thanks.
As others said to much friction. People overthink getting cg. Where abouts are fine, go slightly nose heavy if in doubt and a bird is balanced in the air. Go inverted at a 45 up line 75% throttle and see what the nose does. Of all warbirds I've flown the p47 is a giant trainer when it comes to landing. Massive wing surface area makes for low wing loading. Just use to thumbs or borrow a buddies and cg that way. Of its monocote you can use some velcro stickies to mark cg, makes for easily finding where you marked it with your thumb and also makes it a bit easier on the film.
Perhaps, but because the airfoil is symmetrical on the stab, it is harder to find a zero bubble on the stab without using an incidence meter...which adds a bunch of weight to tail, which then has to be accounted for. Overall...I just find it easier to zero the wing.
Practically speaking, you don't need the incidence meter. Just eyeball the plane to get it close to its flying attitude, and you will be close enough, which simplifies this procedure a lot. Also, I notice the bar of the jig that holds the meter sticks way out toward the nose of the plane. This will affect the CG as indicated by the plumb bob. Let life be simple: get rid of the incidence meter.
Don, firstly, thank you for posting these very interesting videos. Secondly I have a question, why do the giant scale (usually with Moki motor) not use scale (3 or 4 bladed) propellers?
Well...some guys actually do run 3 and 4 bladed props on their large engines, but you need a lot of excess power in order to make that work. 3 and 4 blade props are just too inefficient on our models. The RPM's on our models are too high, forcing each blade to swim in the prop wash of the prop right in front of it. Full scale fighters had gear reduction units. The P47 had a 2:1 reduction, so when the engine is cranking along at 2,800 RPM, the prop is only turning 1,400. Sooo...each blade is cutting nice clean air. Many guys make a big deal of the "Scale Prop Thing". I don't. I fly with 2-blade props. It provides the most power, and the best performance. And that's all that matters when the plane is in the air.
I may not have been clear. It's the full scale P47 that had the 2:1 reduction. In fact, I believe that all the R2800 engines had that 2:1 reduction. At the least, I am sure that the Corsair also used the R2800 with a 2:1 reduction. Full throttle on those engines resulted in a prop speed of only about 1,500 RPM. As for the Moki's...I don't know much about them. Most of the CARF P47's use the Moke 250, which is far more power than is needed for that plane, and so, using a 4-bladed prop is OK. Even so...it's not of scale size, but it does look nice when it's on the ground.
Faux !!! les cordes doivent passer l'une sur l'axe du moteur et l'autre au niveau de la dérive... sinon cela veut dire que vous ignorez la masse du nez du modèle et de la partie arrière. Donc résultat du centrage totalement faux.
Excellent video, I’ve used the rig, it’s the best way to balance her
Excellent and a great P47. Vanessa gives excellent CG and as a RC pilot that's what you should have. Like the big IRON you should use trim for attitude . CG is designed to be in front of Center of Lift thus when the windmill stops turning the nose drops and the designed glide speed is set up . Pilots used to say, :All it takes to fly is airspeed and money" but without you're CG right, you are dead on the money.
Perfect. Exactly what I've been looking for.
Hello Don, I have a question about zeroing the incidence. If a plane have a built in +1 Deg of incidence, which is understood that the plane will fly level at that degree on incidence, is balancing the model at 0 Deg incidence correct since it would not be straight and level in the air. Why not balance the aircraft at +1 Deg if upright or -1 Deg if inverted? I am nor arguing the issue, just asking to learn the system, since I intend to build one and have to learn how to use it correctly. Thanks.
Great videos Don and thanks for the info.
As others said to much friction. People overthink getting cg. Where abouts are fine, go slightly nose heavy if in doubt and a bird is balanced in the air. Go inverted at a 45 up line 75% throttle and see what the nose does. Of all warbirds I've flown the p47 is a giant trainer when it comes to landing. Massive wing surface area makes for low wing loading. Just use to thumbs or borrow a buddies and cg that way. Of its monocote you can use some velcro stickies to mark cg, makes for easily finding where you marked it with your thumb and also makes it a bit easier on the film.
Thanks that was helpful.
Question for you Don: would it not be better to check zero at the horizontal stab rather than the wing chord?
just wondering.
Perhaps, but because the airfoil is symmetrical on the stab, it is harder to find a zero bubble on the stab without using an incidence meter...which adds a bunch of weight to tail, which then has to be accounted for.
Overall...I just find it easier to zero the wing.
Ahh! i see, i think i'll rig up the Vanessa and give it a try.Thanks again for the video and great looking p47 by the way,
from Northern Ireland.
Practically speaking, you don't need the incidence meter. Just eyeball the plane to get it close to its flying attitude, and you will be close enough, which simplifies this procedure a lot. Also, I notice the bar of the jig that holds the meter sticks way out toward the nose of the plane. This will affect the CG as indicated by the plumb bob. Let life be simple: get rid of the incidence meter.
👍👍
Don, firstly, thank you for posting these very interesting videos. Secondly I have a question, why do the giant scale (usually with Moki motor) not use scale (3 or 4 bladed) propellers?
Well...some guys actually do run 3 and 4 bladed props on their large engines, but you need a lot of excess power in order to make that work. 3 and 4 blade props are just too inefficient on our models. The RPM's on our models are too high, forcing each blade to swim in the prop wash of the prop right in front of it. Full scale fighters had gear reduction units. The P47 had a 2:1 reduction, so when the engine is cranking along at 2,800 RPM, the prop is only turning 1,400. Sooo...each blade is cutting nice clean air.
Many guys make a big deal of the "Scale Prop Thing". I don't. I fly with 2-blade props. It provides the most power, and the best performance. And that's all that matters when the plane is in the air.
Thanks for clearing that up Don. I was wondering about the gear reduction on the Moki.
I may not have been clear. It's the full scale P47 that had the 2:1 reduction. In fact, I believe that all the R2800 engines had that 2:1 reduction. At the least, I am sure that the Corsair also used the R2800 with a 2:1 reduction.
Full throttle on those engines resulted in a prop speed of only about 1,500 RPM.
As for the Moki's...I don't know much about them. Most of the CARF P47's use the Moke 250, which is far more power than is needed for that plane, and so, using a 4-bladed prop is OK. Even so...it's not of scale size, but it does look nice when it's on the ground.
Thanks Don. I really enjoy your videos! You are quite the consummate artisan.
Thank you so much. Man, I'd love to sit and talk with you and pick your brain.
Well, you know...Just drop on by. :-)
Bring beer.
Faux !!! les cordes doivent passer l'une sur l'axe du moteur et l'autre au niveau de la dérive... sinon cela veut dire que vous ignorez la masse du nez du modèle et de la partie arrière. Donc résultat du centrage totalement faux.
There is obviously a lot of friction in jig and ropes friction defeats the purpose of free balancing it . get two friends with strong fingers
too complicated
Over kill. !!