before i begin this aircraft was first designed by Mr. Patrick Peebles and all the info about fanwing experimental aircraft can be found at


i had been researching this topic for the past few weeks and thought that the time to start the build had come. so today morning i finished up my calculations for the dimensions of the wing - blades , outer edges and the rotating mechanism.  here are some of the calculations

Cross flow Fan outer Diameter = 10cm

outer edge circular blade holders thickness - 4mm balsa

Wingspan = 100cm --> Built of two sections of crossflow fans with opposite blade declinations as shown here (each section futher sub divided into 2 more sections)


blade thickness - 2mm balsa

no of blades - 24 at every 15degrees on the blade holder

distance between blades -          angular  - 15 degrees
                                     circumferential - 1.308cm

Blade width  - 1.5cm

carbon fibre central fan spar diameter and length - 2 spars of outer diameter 1cm and length 50cm

motor - turborix 2836 222w 1000kv

gearing and belt system  - hobbyking gokart belt system

esc - 30A

Battery  - 11.1V 2200mah 20c

Radio - RDS8000

Contruction - wing - balsa
                   fuselage - balsa and depron
                   tail feathers - depron and cf rods

I began today by cutting balsa for the first half of the crossflow fan, i finished outer and inner blade holders and sanded them and one blade 23 more to go

Subbu

some more pictures

Subbu

Subbu, a thousand years ago, when I was a child, my Dad had bought me a toy from Germany,  that had rotating wings. It looked like a plane (fuselage) but the wings were designed to rotate horizontally about an axis. It was essentially a kite for gusting winds and designed for the sea beach.

I held on to one end of a string roll and the other end was attached to the model / kite. As the wind picked up, the wings started to spin about their axis, causing it to lift. I remember that it was great fun.

This seems to be the same principle. Must try and build that toy again............ Coroplast should make my  job easy! Thanks for taking me back to my childhood.

Same found in juhu beach and one is with me.
But it needs Airflow velocity > 20KMPH (Appx) which can found only in sea beach.

It's 17" wingspan with two rotor wing of 8" x 2".



Related Links :
http://www.ict.griffith.edu.au/anthony/kites/rotor/

great...even i bought it for Rs.20 from juhu beach long back......
Sandeep

Oh my God! That's the one! I would love to have one again. Requesting people who have access to it to please send me 5 pcs.I will pay for all expenses.

waiting

you are welcome vc bhaiya

as for progress i have finished making slots in 2 of the three outer blade holders and cut out a few more blades total blades  - 4 will post some pictures in the evening

Subbu

here is the gearing and power system i shall use for the crossflow fan

Subbu

where did u get these from...?? any links  please...!

sure why not i got them from hobbyking here are the links if you wish to buy them i have them posted on the hobbyking buddycodes page too
buddy codes are valid till 7th june

Belt - Go-Kart - http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=15342
Buddy Code - http://www.hobbyking.com/buddy.asp?code=5DFC140F-1883-429F-8475-ECD5725D96D8

Pinion - Go-Kart - http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=15363
Buddy Code - http://www.hobbyking.com/buddy.asp?code=EDC15E95-07FC-4673-838B-BF9234CC8537

Spur Gear Assembly Set - Go-Kart  - http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=15343
Buddy Code - http://www.hobbyking.com/buddy.asp?code=BB8A2655-3573-49FC-91ED-28352B9A99D7

Drive Gear - Go-Kart - http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=15341
Buddy Code - http://www.hobbyking.com/buddy.asp?code=1EE2E3E6-C267-4FAB-B7C5-D28F85640F69

i got the motor from sai uncle but i dont think you were looking for the link to the motor anyway sai uncle does not seem to have this motor in his catalogue on the website anymore but you might still try calling him

Subbu

  now this is jara hatke...  

good purchase...!

  waiting to see this in action

btw what is advantage of this over normal prop.?

hi karan
conventional propellers propel the aircraft henceforth creating airflow over the wing thus generating lift whereas the cross flow fan on the fanwing itself establishes airflow over the wing of the aircraft essentially making the wing generate lift. a few other advantages are that it has very little to none stall tendencies, higher lift compared to normal propeller and STOL (Short Take Off and Landing) ability.

so after an all nighter tonight i finished with the blade holders. i still have to sand them.
i still have a lot of blades to cut and install the carbon fibre central spar. anyway i have attached the pictures of progress below


Subbu

and another picture

Subbu

what are the gear ratios (ie. input : output) also pinion and gear dia and shaft sizes....

Wow............
Really Innovative...
Subscribed!!!

 

hi aerovishwa here are the details that you requested with reference to the pictures

pinion diameter             - 15 mm
input gear diameter       - 50 mm
output gear diameter     - 30 mm
pinion shaft diameter     - 3mm

I --- if i use the given setup the gear ratio comes out to be  --->  2:1   (input : output)
(which should step up my wing rpm from the motor rpm of 10000 to 5000 for the wing)

II --- if i mount the motor on the input gear (somehow) and make it one huge pinion i get the ratio --->  3:5 (input : output)
(which should step up my wing rpm from the motor rpm of 10000 to 16666.6 for the wing)

i plan to use the first (I) setup which is also depicted in the photo below but if the lift is too less i shall go to setup II

were you looking for any other dimensions when you mentioned shaft sizes other than pinion motor shaft diameter if any please mention.

thank you sumeet

Subbu

thanks a lot that helped...!!

how do u plan to check the vibrations in the fan wing...? it  will play an important factor  in  such a huge fan...!

also dont u have to  channelize  the thrust in  one direction... or does it work  on some other  principle I am  unaware of...! JUST EGER TO LEARN... 

Subbu, this is getting complex and interesting. Keep it up. Unless I missed it, what is your plan for the fuselage?

Btw, can NO One get me a Juhu Beach flyer @ Rs.20/- + inflation? I've had no offers so far............

thanks for having brought that up because the biggest challenge in this aircraft is to reduce VIBRATIONS whenever and wherever possible. a few of the methods observations and plans i shall use
1 - using ballbearings on the CF spars where they attach to the frame and assemble the gearing system on the CF spar end. this shall very nearly kill the main source of vibration that is mis-allignment.
(will get some 3d renderings up soon)

2 - to get each blade precisely cut is not a feat i shall be able to manage since i don't have access to a cnc facility (but a lot of members here do so if my handywork does not work then i shall have to give them to be cnc cut (IT WILL SAVE YOU A LOT OF TIME))

3 - due to me using 2mm blades there is a huge chance for the blade to flutter adding to more vibration henceforth i am attaching a third blade retainer in the center of the wing (refer the photograph), after the initial proof of thrust generating capability of the fan i am thinking of covering the blades with fibre tape to increase rigidity.

4 - finally i will try my best to level out the wing on both sides before first spin to reduce any contributing vibrations there.

these were the ones i could come up with yet if you have any specific issue in mind kindly mention it, it might  help me spot the flaw

regarding channelizing the thrust the crossflow fan takes care of it the angled blades in each half help accelerate the air over the airfoil to generate lift. in this process a lot of air is pushed back and down and this give the aircraft the minimal thrust it needs to move ahead (much like that of an EDF fan). please also refer to the attached picture 1.

this down draft of air prohibits the placement of tail feathers behind the wing and therefore that has to be elevated as shown in picture 2.

hope these answers help you

Subbu

u said u would need a 15degree  blade  angle... but looking from  the pic i suppose that every   bladeis in straight line  with the center....!!(pic)

also since the angle with the center is zero it will possibly blowout air from all  sides...!
OR AM I MISSING SOME THING

please post  from where are u are referring the  design or is it ur own..!

here on the right side there is a GIF u can see there that u  need 15 degree with the dia line...!

http://www.fanwing.com/desc.htm

a closer look here will also reveal the same....

http://www.fanwing.com/news.htm

hi VC bhaiya i have planned to use 6mm balsa bulkheads with balsa strips to create the skeleton of the fuselage and then use depron for the outer covering. the crucial part is where the wing joins the fuselage i plan to make that completely out of balsa. the plane needs to be light too so i am thinking of swaying from the fuselage mentioned in the original fanwing build but instead go with simpler stick like or a flate plate like fuselage as i have no previous experience in building complete fuselage out of balsa bulkheads and strips but i have made the fuse out of depron for my 747 build http://www.rcindia.org/electric-planes/61-inch-boeing-747-300-electric-ducted-edition-build-log/ and i can replicate that technique here.

would you have any suggestion in this matter. the mention of my 747 makes me want to have another go at it as i have another complete month free to build it but testing it would be difficult as rain gods have started showering their blessings here in mumbai

as for the Juhu Beach Flyer i am going to sushil uncle's shop in the next week for a soldering tutorial he has agreed to conduct for me so i should be able to visit the beach and scounder for the aircraft at least worth a shot.

Subbu  

Thanks Subbu!

i am referring the same design and yes aerovishwa the part you missed was that

1- the blades thickness is only 2mm and the breadth is 1.5cm (length being 50 cm) and
2 - also that 15 degrees is not the blade angle but the angle subtended between two successive blades.

these dimension were rescaled from the orginal to fit the 1m wingspan and due to such thin blades contouring the holder to give the airfoil like shape to the blade itself with the balsa would make it break due to very small breadth and make the holder very weak too.

to counteract this the three main blade holders have been offset by about 2-3 degrees from each other thereby gradually bending the blade throughout the wing and creating a blade like structure. kindly refer to the pictures being attached.

i had another alternative to make the exact shaped blades that is using the metallic film used in the measuring tape since it already had the contour.

for any other clarifications please ask since it also helps me scrutinise the integrity of the model at every point thanks

Subbu

just check this again...!! having all the blades in one  direction(all axis meeting at same place) i have a big doubt on  that...!! of setting will  be not  be of much use  if u wanna to push the air  in one direction... it  will just blow off from all sides

what i suppose  to mean

ooh sorry now i get what you wanted to tell me about

that is one area i had not thought of yet i will definately have to count that one into the design i will design some new blade holders after calculating the exact midline bank angle of the blade from the diameter line tomorrow morning itself.

but i would still love to experiment with the above ideas i had mentioned earlier of the blade holder offset since i did refer to these aircraft photographs too on their website and the second photograph shows no blade angle but has a slightly curved surface kindly refer to the attached photographs.

another interesting thing i noted while i was departing from mangalore airport was that they had an air curtain device which had the exact crossflow fans inside it which i am looking for if anyone has any information on them please mention it here

thanks a lot aerovishwa for pointing it out

Subbu

EDIT - the first photograph shows no blade angle
           the second photograph shows the offset technique

the air curtain exactly....!!!


just drop  by your local super market or any mall...u have that on the entrance ..... just check that out for the blade or  even some thing  like this in someones house...!

http://www.symphonylimited.com/products/DiET-50E.html

the first pic  also has some offset...in  the center  a close look  please...!

yes i see it when i look at the center the blade does have a slight angle to it. tomorrow (i mean today since its already 1 am) i shall be dedicating the whole day to the project and hopefully will get the fan with the new blade angle offset holder ready. and try out the gearing system.

i would still do the original design also and compare them together to see which one performed better. hope to get a lot done today (later after i wake up).

thanks a lot aerovishwa (i would love to know your name so that i could refer to you easier)

Subbu

Edit - i shall also see if i can get my hand on one of those air curtains

alright, i see a lot of eyebrow raised on fan wing. things about fan wing, it is a not a new concept, shelved due to weight penalties (Olden times engines were heavy and had poor thrust to weight ratio), modern laminates and engine tech is reviving fanwing agan for its very obvious advantage of very less Lift Induced drag and therefore small efficient engine and less cost of operation, to understand fan wing you need to understand the Circulation theory of lift. read this and the subsequent post to understand Circulation theory of lift

http://www.rcindia.org/rc-general-topics/basic-aerodynamics-for-rc-flying/msg105113/#msg105113


and this

http://www.rcindia.org/rc-general-topics/basic-aerodynamics-for-rc-flying/msg105115/#msg105115

thank you for the informative post on the circulation theory of lift gusty bhaiya

as for the progress i am posting some of yesterdays progress pictures i cut out all the 24 blades and 4 extra ones.(which i forgot to post)

waiting on sushil uncle's advice on epoxy coating the blade holders to give it additional strength

i have started with the gearing part on the motors side and started with the mounts photos to follow on this soon.

i have attached the pictures of the blades with blade holders the rubberband on blades makes me feel like i am building a kit  

Subbu

Edit : Vishvesh i am thinking of getting the angled blade holders CNC cut in light ply as shall be done for the final prototype as cutting it from balsa takes a lot of time if i cannot get the cnc cut out cheap then i shall cut it out in a few days after testing this prototype

Got a beautiful gift from Subbu / Pickle. Thanks also to Sandeep (If I am not mistaken). Got a bit of my long lost childhood back.

whenever you do maiden the aircraft please take a video of it, this thread would be incomplete without it 


Subbu

hey subbu...! nice update..

just make  a drawing for the blade holders, scan it or directly do it in PC..and send it to  pradeep (PVA models)....  he can get u that laser cut in balsa  ply.... will work out great...

PS: pradeep, please  do that for him....

thanks a lot vishvesh for the contact i will surely contact him, i was only wondering where i could get that done from.

as for the update i got the main spur gear and the motor with the pinion assembled in a mount. testing them out right now

here are a few pictures


Subbu

one question stands is....! how are u  going to  mount that on a  plane....?

u said  u are going for a profile fuse...?? u need to have a entire  built up for this...!

again send the  plan(of fuse) to pradeep.. he will get it laser cut..!

vishvesh that is true. but before i went in for a full fuse model i decided to test it as below

the crossflow fan section i have built until now is only half (50cm) of the complete 1m wingspan of the aircraft. i am planning to split the present section in two then use my above gearing section to have it connected at the centre to drive the two 25cm crossflowfans. then i shall finish the fans by adding the airfoil curve behind the fan and undercovering of the fan. then i plan to mount it on my 1.9m glider (picture attached) and onto that mount this setup as a semi biplane wing and then see the performance of the fanwing design with glider power OFF and fanwing motor ON and all other combinations. if the design works i shall get the lift i need and then shall move on to the full fuse.

as of now the gearing system works beautifully here are some pictures attached video being uploaded to youtube right now


Subbu

this is what i am worried  about....!
ISKE TOPI USKE SAR....!

just design a new fuse and get it done....! also u need to  consider the position of the tail( elevator) u cant have it in the glider.... it should be lifted..remember....

i dont want to put your tail in the wing wash... ( its gonna be a hell lotta turbulent...!)

oops i forgot about the downwash the tail would have to be elevated you are right i will have to design a full fuse i shall get with designing the drawings right away for the cnc. thanks for the reminder  

l have no experience in built up fuses as far as i know you have bulkheads and balsa strips to get the basic skeleton and then you have to cover or sheet the plane is that right ?

17 more minutes for the video to upload


Subbu

this one is going to be a long one

i am posting a build log,....! just planning away to  compress the photos u can have alook on how it is done there....!

u have formers and sides...! no strips( atleast in  simple ones...)  PVA models can do that for u..!

thanks vishvesh which build log are you referring to?

Edit : Found it will keep an eye out for the sonic

i will speak with pradeep from PVA models tomorrow morning.


Subbu

i am planning to finish my quad build (not configuration) tomorrow after that have to finish up the tilt mechanism for V22 osprey

 

check i have posted...!

looks like u have lots of things in  hand...!!

one  suggestion.... do one thing at a time... else u will  end up in  confusion..! like u forgot about the tail in this case..!

i really do have a lot of things at hand since i am leaving for college at manipal in exactly a month, i wanted to conquer as much as i could  

your suggestion has been duly noted

the video has been uploaded here it is


the audio quality is very bad i am not sure why

Subbu

what battery  are  u  using 2s or 3s.... u  need low RPM here...! ( else  there will  be a huge vibrations..!)

i am using a 3S this is just a mock up as mentioned i shall have it cnc cut and also shall order some ballbearings for the perfect fit of gears and blade holders

ball bearing will be good.... just goto your  local SKF  store.. u will get whatever size bearing u want..!

also try and use 2s...!

as of now i dont have any 2S battery but will order one tomorrow from an LHS or HK.

SKF???


Subbu

SKF is an  indian  bearing company... known for  precision bearings and quality..... they have outlets allover india..!  I replace my motor/engine  bearings got from  them...!

got it will go on a hunt tomorrow good night everyone

Subbu

hope will help you. http://www.gizmag.com/piloted-fanwing-aircraft-debut/23398/

good day sir..
iam planing to make a rc fanwing with twin tail configuration with a wing span of 1m or 1.5m..
can u plz help me with dimensions n design?

Hi pikle6
I have seen in the very beginning of your post that you have done some calculation on the span length , no. Of blades and distance between them etc.
Can you kindly advice a reference for those calculation based on what?
Appreciate your quick response

I have few questions for you ..
what motor you are using ? what is the total weight of your aircraft ?How will you place your motor for driving you shaft(for rotating blades) ?

Hi Pikle6
How did you arrive at these dimensions and specifications?
Did you have some references to begin with?
Some insight as to the calculations would be great

thanks

I am also currently working on this topic and would like to get in touch with you regarding further information on this topic. would be helpful if you would share your email id so that we can get in touch.