A step by step method to calculate the wing size (or the total lifting surfaces) for your plane, in order to have a convenient wing load. You can also check if your plane is a good flyer following the cube wing load criteria
I’ve made a plane with a C value of about 11 and it flew but it was so hard to control that I crashed it multiple times. I’ve made a new design with a C value of around 6. I’ll reply with my findings on how much easier (if at all) it is to fly
Your video saved me a lot of time and money. Thank you. I do have a question for you though. You substitute C with ASE. Nowhere in your presentation can I find what ASE stands for. Can you reveal that, please? Thanks again. JT
it was confusing at first...but I figure it out. Which was helpful. Thanks Im scratching off a 3D plan. it was right on the money or at 10. But I dont really need it to fly 3D...it's just for simple build. Which is a struggle. Then force to use the same size batteries and build like pro... which isnt going to happen. Im most liky going to over build or be on the heavy size using foamboard. which will tip me to a flying brick...brick or use a lighter battery and get 3-4 mins of flight time...(NOT).lol i was going to clip the wing to plans... Im not now...the extra inch wing span will cuase more drag but will bring the model back under 10 ( for the extra wiegth I might incure) Now i can figure out the proper motor and prop combo for the drag and wieght. Torque is what I want...not top speed. Even if I build lighter...it's not going to drop to under 6.
Hi Mel. The required area has to do basically with the wing load, but the airfoil has a lot to do with the type of flight. If you have a trainer or a jet, the airfoil of course is different. Also, the airfoil has to do with the drag. Thicker the airfoil, grater the drag,
@13:05 the dimensions of wing expressed in which unit. Mine dimensions are 1) Wing Root chord-440mm, tip chord- 120mm, wing span (one side)- 427mm. 2) fuselage a)Central fus- length- 680mm, width- 390mm. b) Forward fus- length- 785mm, width- 390mm. Plz help me to understand calculation
Iam having a rectangular cross sectional fuselage.....my question is that...I don't know whether I have to add this fuselage area to the summation of lifting area...pls say about it
If you could get a real voice and maybe use cm³ (I know it's not the standard unit but it's something more commonly understood) Otherwise brilliant info.
Hello Paul. Sorry for the delay. ASE is the calculation of lifting area to the power 1.5. I made tables of ASE so you do not have to calculate it. It facilitates the other calculations as explained in the presentation.
Hello; Your videos are very good,but I still don;t know how to calculate the power of 1.5 with wing loads and weight,,,can you explain how to use it...its me,I have a hard head to learn new things.............
Hello Paul. You don't need to calculate it because is already calculated and tabulated in the presentation. C= total weight/(Lifting Area)^1.5 to facilitate the calculation I call ASE =(lifting area)^1.5 , so if you have the area , you look in the table and find ASE . Once you have ASE calculate C and see what value you obtain. (less that 12 is OK) On the other hand, if you can go the other way, if you want a defined value of C (say 9, for example) you can calculate what area do you need in your model. Once you have the area, you can determine the wing according with the type of selected wing.
Ok. you have area=46 dm2 (eq. 1) and wingspan/chord =6 (eq. 2) . From eq.2 you have chord= wingspan/6 (eq. 3) Now you put eq. 3 into eq. 1 and the result is wingsapn = SQRT(46 x 6) = 16.6 dm . Once you have wingspan put it in eq. 2 and you have the chord = 16.6 / 6 = 2.77 dm or 277 mm.
Thanks for asking. Using the formula to determine the surface needed for a load, how does thrust/airfoil/drag factor into something that flies given the determined surface/weight result? It seems to me (aeronautical ignorance here) that to achieve any degree of lift, the wing profile and thrust must factor into actual flight. For example, I have a given load (70g) and a given motor (35g thrust). How is the surface needed to carry 70g related to a design that has 35g thrust? Does surface area change based on thrust?
@@melristau If you my video on How to choose a motor: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-EL1vt9ufEcE.html There is a table at the beginning that relates the thrust/weight ratio according with different types of airplanes. This table is of common use by aero-modelers. There I propose a process to select a motor and propeller that has proven to be useful for the hobby. It took to me a considerable time to understand the relationship between all this variables and to put in few words all the information. Hope it will be useful for you too. I am not an aeronautical engineer, but a mechanical engineer trying to put some of what I have learned by experience in the hobby.
Thanks! Did watch. The plane I’m trying to design is based on an RC system with max thrust of only 35g! + a total load of about 70g. The lift area is what I’m experimenting with. 🙈
from the expression 26 dm2 = 0.38*WS^2 , now solving for WS^2= 26/0.38 = 68.42 from here ==> sqrt(WS^2)=sqrt(68.42) = 8.27 dm or 827 mm. (Sorry for the notation, it is difficult to write mathematical expression using the standard keyboard)
thanks for posting. pretty good presentation. here are some things to consider. wing loading NUMBERS are Secondary to the general Management of mass and a model's ALL UP WEIGHT (auw). a horizontal stabilizer (not elevator) of an rc model plane, Should NOT Make LIFT. where auw is Not excessive, achieving optimal wing loading is Simply a matter of adjusting the auw. each component part of an airframe Should Be designed to be Functional and LIGHT. model builders Should learn about the part Distribution of MASS plays in CORRECT airframe design. the Ultimate wing loading of a model is a Consequence of ALL design choices. INCLUDING, choosing to make ALL COMPONENT PARTS AS LIGHT AS PRACTICAL. where MASS is not Optimally 'located' in an airframe, even if the model can be correctly balanced, its Wonky Distribution of MASS, DOES NOT GO AWAY BY ITSELF. at 8:44, 1.54 KILOS. this is so much heavier than A small model should weigh. a meter-span model COULD WEIGH twelve OUNCES, instead of two-plus POUNDS. in nearly all cases, where NON-traditional model building materials are used, a model Will be heavier than it COULD and should be. one solution is to make a Bigger model, which would require the use of a correctly spec'd power system. cheers googletranslate some resource www.princeton.edu/~stengel/MAE331Lecture5.pdf wright.nasa.gov/airplane/shortw.html s3.amazonaws.com/assets.flitetest.com/article_images/medium/truecg-jpg_1384168691.jpg illustration, not fully accurate; each design should include the use of a center-section 4.bp.blogspot.com/-2--h6sQm6gM/UbHzoXWPxYI/AAAAAAAAUiI/sn7cWnVlkuQ/s1600/polyhedral.jpg
I have never seen wing cube loading for big aeroplanes. Why...? Perhaps because the term is not for real. Instead use the thin airfoil therory. The big difference between a full scale an model plane are. The measurements are scaled down say 1:10. That means the wing are is reduced by the square if the scale factor. So the wingloading must come down by 100 in case of a 1:10 model. Also when we fly slower the lift is reduced by the square of the reduction in speed. So - calculate the CL (coefficient of lift) of your model by wheight speed and span. Kepp the CL the same as a the real plane and you’ll be fine.
