CENTER OF GRAVITY
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- čas přidán 25. 07. 2024
- What does Center Of Gravity mean and how to design your airplanes with understanding of this aerodynamic parameter. Also a discussion of aerodynamic center, center of pressure, and neutral point as they relate to the COG.
Canard CG calculator:
adamone.rchomepage.com/cg_cana...
Flying wing CG calculator:
fwcg.3dzone.dk/ - Věda a technologie
That was the best explanation of CG I have heard. The point about the CG moving forward on a high wing and backwards on a low wing is very interesting. Ill have to watch this several times to absorb all that you explained, but really nice . Thanks
Because the centre of gravity is a measurement of calculation of weight and balance, a change of angle of attack does NOT change the centre of gravity. However, a change of angle of attack does change the position of the mean centre of pressure relative to the cenrre of gravity.
I subscribed today after watching several of your videos. Your teaching style is fully informative, easy to watch and learn from, and strikes just the right balance between detailed and concise information. I have learned several things today that will be very useful. Thanks!
Well done and informative, I liked your mini airplane, it helped illustrate the concepts.
Can you do a design series to address picking wing size (cord and length) and stabilizer size/shape (maybe even talk about v-tail/inverted v-tail too)
wow! So good to have you back Ed!
Your videos are inspiring and empowering. When I watch them ideas for cool planes spring into mind. Thanks man.
Love the way you structure the
Speech so any one can completely
Understand what you are teaching you definitely have
A great gift for teaching I thank
You for giving all the correct info
To us that try and fail in rc world
We still miss you, Ed.
When I recommend this EA video to new flyers/builders, it always amazes me how much they improve in both building, and flight.
YOU ARE THE MAN, ED!
THANK YOU!
Hope you're doing well!
Where did he go ? Is he ok ?
@@endliberalism4305 no
@@isaiahraines122 what happened with him😮???
@@MOONsRCPLANES. - He appears to be ok. Seems he just got too busy professionally to make more videos for CZcams. Happens. czcams.com/video/TfNiZX1ukyM/video.html
Heyy, I really don't know how to thank you for this video. You're just so good at explaining and making it easy to understand.
I understood everything the first time Ed, Thank You. From Now On, my 'Frankenplanes' will likely have more success..
Great video and perfect timing! Thanks so much! This video will be very useful!
I can recommend this video to anyone. Thanks for your knowledge!
you explained that REALLY WELL. Thanks for the video!
Thank you so much for the info. You made my day. Keep up the good work.
What a great video sir 👏 there is just no substitute for brains 🧠 . This will definitely help with my thought process in my next build 🙂.
Great Video!! Thanks. I too would be interested in the links you mentioned.
I am curious about Bi-Planes and how the second wing affects COG depending on if the wings are staggered or even with each other. Crazy me wants to add a wing to a DTFB Texan/Harvard I built.
Love this!
Any chance you could explain vortex generators as well?
Very good CG explanation & very understanding. Thank you Ed.. 👍
Fantastic explanation. COP etc never gets explained. Useful to know there's more to it.
it was not explained correctly HERE either. CP varies under aerodynamic load...CG NEVER does. They are not the same thing.
Thank u for taking time to make this video that helps a lot in learning about cg.
Very good info, I'm rebuilding a kitfox and trying to do this full scale. I plan on using a heavier motor, so now I need a larger vert stab and elevator?
Thanks for this video! Cg has been a constant aggravation on my builds. I now understand what the moment arm means and I see what has gone wrong with some of my builds.
I am a fan of bi-planes, any possibility of an EA bipe?
That is really helpful. Thank you for sharing the knowledge of stability. :)
I don't know whether you will read this, but neutral point of a wing varies with angle of attack, and is usually between the leading edge and the middle of a wing. Why? the bottom part deflects air equally throughout whole chord,while the top does majority of deflection at the front, because that's where the air has to change direction to flow with the wing. nearing the trailling edge, the air is not deflected as much.
Professor EA! Thank you!
this video was very helpful, just one question, to find the visual point that the plane is level so I can balance it with that as a reference and then make a touch nose heavy, would using a spirit level on the tail give the angle at which the plane in general is level?
Thanks a lot for putting your videos together. Super helpful for the first RC airplane I am putting together. By training, I am a mechanical engineer and understanding the concepts in relation to various moments generated is very helpful. One quick suggestion: at around timestamp of 7:00, it would be helpful to add a subtitle saying that the presumed airflow is going into the screen and towards you.
The more i learn the more i wonder how any of my scratch builds fly lol! Great video.
ive built 4 and none of them flew
I built 4 and only 1 flew
I've built 3 and they flew only for a few seconds lol
This is what the Wright Brothers went through!! 😋
CoG is probably the most important thing on any Aircraft design.
czcams.com/video/PZ7yrMSEjx8/video.html
Best video on this subject out there!
This is a great explanation. Thanks!
Very cool explanation! Really helps to understand, what's going on in what case....
Big thumps up for that video!
What calculator do you use, to find the cg on a swept wing or a deltawing?
+Stickmix FPV Darn, meant to put those in the description. Look there now.
+ExperimentalAirlines Superb! The cg calculator is the same I used. the other one is new to me. thank you.
Did you make that model plane?
Stickmix FPV wedghll
Really beautiful plane. Please, it is possible for you to share the design and electronics specs of this orange and yellow plane? I would love to build and fly it.
Great video, what about the design where the prop and electronics are in the back of the fuselage?
Great video as allways ....
Except for R/C airlanes expected to do intricate aerobatics, I have found that a horizontal stabilizer/elevator with greater area (I prefer more span to more chord) is the best way to go. Many an otherwise nice model has been made virtually unflyable with a too-small horizontal stab.
By doing this, as you have said, the aerodynamic centre moves rearwards and if a light building technique for the increased stabilizer is used, the CG will not move rearward very much. This will, of course, increase the distance between the aerodynamic centre and the center of gravity, thereby increasing pitch stability. This is much to be desired for sailplanes and free flight models.
I love all ur vids :)
Can you do an intro to fpv vid modernized as part of noob tube
Thanks for the video. To me its a need-it-right-this-second thing: was questioning at RCG. What about the APD? Is the cg located in similar range?
Growing up flying models with my dad he TOLD me the samething, if your airplane balances between 25 to 33% of the cord on a stright wing it will fly.
Using that rule of thumb I have built many single boom and twin boom pushers and they ALL flew very well.
Great video, I'd love to buy one of those planes from you, they look easy to make.
As always! your videos are superb very explicative and very simplified for noobs like me! do you have any recommendations for further reading If one would like to have a more precise/correct version/explanation of CG in particular and model aircraft design in general
Hi there! Thanks for the great video!
Referring to 3:59, I don't think the centre of gravity is moving (it's a property of the body regardless of it's orientation), I guess you get additional stability because the centre of lift is shifting backwards.
hi. May Allah give you long life. you are the great man. who explained very easy talk way and with the showing of examples.
Thanks for the information
But how do i find cg of a plane??
How did you find the CG and moment on the Ansley peace drone?
Awesome tutorial!!
Thanks I’m starting my own design. Nothing to crazy but this is very helpful
Your videos are a great help for young modelers like me! Thanks a lot!
I think it would be clearer to explain the difference between and the relationship of the centre of LIFT and the centre of gravity.
If kerbal space program tough me anything, it that Jeb's nuts. Nahh just kidding, it's that you put the center of lift behind the center of mass. Not by a lot, but comfortably close.
@@chrisbolland5634 czcams.com/video/P_0R0eWOKns/video.html
Can't agree more 😃
Great video!
How much curved wing's upper surface need to parfom efficiently and how much redias liding aedj need
So help full for sure.......
So on a new plane I should place the battery so that the middle of the battery is directly over the center of gravity line ?
Which airfoil did you use sir?
Great Videos Man!!! You have a new channel?
Ed-
Another wonderful explanation.
As you were explaining that the CG is 25-33% of the airfoil, I was saying "What about the control surfaces"? ... Then you got to it.
My question is regarding your recommendation to only consider the cambered portion of the wing in the calculation - "resulting in a conservative solution. It seems to me, that considering the shorter of the two sections, would move the "Calculated CG" forward (25% of 6 is 1.5 and 25% of 7 is 1.75). This calculation would tend to "favor" a tail heavy situation. I always thought that -"nose heavy flies poorly, tail heavy flies once..." Am I unbalanced?... All I know is that you designs fly great!
Thanks-
Tim
good point moving it forward does make it more tail heavy. Further issue is that using the recommended low end of the range, 25% makes it even more tail heavy. Conversely if you used the other end of the range (33% of 6 is 2.0 and 33% of 7 is 2.2) That makes the rule of thumb range of .70 (or less than 3/4", not a huge amount in the scope of things)
hey ,
What materials were used to build YOU aircraft, and thank you in advance ?
what about if the wing in my plane is not straight but back swept a bit, how to get CG on it please?
Nice video! When designing our own plane, should we keep both side of CG have the same weight?
Any ideas on why with the 737 Max. Boeing has set the VIT maximum tail trim limits to render the elevators useless. Are they thinking extreme nose/tail loading and forgetting it may be either way and then allowing even more trim via MCAS. Surely that trimming method even with a faulty sensor input must never be able to overcome elevator control, because at the moment it most certainly can
excellent channel you my go to guy now bro
Super helpful,. Thanks!
Great explanation ..
👍👍
and the gyroscope effect on the rotor of a chopper are affecting too
would be nice to see something like this for canards.
And what about the flying wings or delta wings?
damn.... this is a great video!!
What inch cg put you in this plane sir from tha leading edge how much Inch
I like these theory videos.
Thank you for explaining in details.
Could you please explain more about how you make your own rc plain.
how to calculate neutral point of plane?
very well explained
Hi could You please recommend cheap motor.
please check at 3.46 you say cg varies with aoa. I do not think this is correct. The cg remains the same but the center of pressure varies with aoa.
true , that statement bothered me too.
I was looking for this comment, glad you mentioned!!
right
If the center of gravity is where the aircraft balances, and you don't include the control surfaces in the chord length to compute the c.g. on the wing, that seems to me that this would result in the measurement being forward of the c.g. - so wouldn't that make the airplane tail heavy instead of nose heavy? And if the center of gravity is where the aircraft balances, how can it possibly change depending on angle of attack? Is my understanding of what c.g. is skewed? Am I perhaps improperly equating it with center of mass?
Ed, any interest in creating an "Experimental Airlines" FaceBook group for people to post their experiences?
Thank you.
sir,I have a Question??
good video , top bloke
Wooow, excellent explanations thanks
You are my teacher!
شكرا"للتوضيح
Drawing circles around the pivot points of the control surfaces will also help (or bubbles in an imaginary sense). I also wonder if a discharged battery is light weight in comparison to a fully charged one or both extremes do a difference in the aether. A motor full of magnetism certainly mess with what we can't see. :)
Thanks for explanation
Hey, I just actually noticed a chap (Rog) with concerns that are just so similar to mine. I've been posting my concerns for months with sometimes even pilots poo pooing! although with the Senate and House hearings in the US. concerning the Boeing 737 Max crashes. Negative postings to me have gone quiet. So maybe, just maybe..even another fix.
Excellent video! Let me know if you're in Los Angeles, I will buy you a beer :)
thank you ... good video
Very cool video, I learned a lot from it. One question/smartassism: you say twice that the components on the back are adding weight "disproportional" because of the long lever. Shouldn't it be "proportional" because of torque=distance*force .
+foamidable From a strictly physics standpoint, yes. For builders with less knowledge in that area I was trying to convey that stuff mounted far rear of the CG has a larger effect than mounting the same thing in the nose closer to the CG. It probably wasn't the best way to describe it though.
There must be a reference point where I can use a level and to determine if it is level. I’m not sure a visual observation will suffice to knowing when a plane is level especially on larger RC planes.
I had a similar concern. In the YT video titled "Vanessa Center of Gravity Machine," there is much discussion about placing a level on the horizontal stabilizer. Even adding an equivalent weight at the front of the plane to equalize the weight of the level.
I like this video education. 👍👍👍👍👍 Thankyu mister.
Nice explain sir,
Hey u need to build a pylon racer 800mm -1m wing span
at 3:43 you said COG will shift by higher angle of attack? How will it shift? I thought COG of an object doesn't change.
The CG stays the same in the airframe, yes. But it changes with regard to the wing and the airflow around the wing. The farther the cg from the wing line, the greater the effect.
how do you MOVE your cg BACK to the middle of plane
wow you answered most of my question...thanks
Center of pressure moves forward with aoa not rear
What happens if the aircraft is tail heavy?
there is am adage that says a nose heavy plane flys poorly and a tail heavy plane flys once. ie it crashes
10:17 Got a stupid amount of nostalgia joy from seeing that nose weight. Haven't seen or touched one in decades before today.
Sir where are you??????
Sir we miss you 😢
Please answer
Where are you now😔
Great info. This is perfect for Noobs like me.
Hornet Centro de gravedad??
Or, use the main spar. Done.