HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Sep 19, 2014, 01:08 PM
Registered User
Altbob's Avatar
Joined Oct 2012
209 Posts
Build Log
Chitty Chitty Bang Bang

Chitty Chitty Bang Bang was my favorite movie as a child, and when I had a son of my own it became our favorite movie to watch together as father and son. We wore out the VCR version and then later got the Deluxe DVD edition and we've watched it more times than I can guess at. At the same time, I've also passed on my interest in aviation, and before getting into RC planes together about 3 years ago, we cut our teeth designing, experimenting and flying paper models. The closest I've come to scratch building an RC plane was a Slow Stick I put together last year, but the experience taught me how to solder and wire up ESCs, motors, receivers and servos, find CG, etc. I've done a bit of reading about airfoil design with dollar store foam board ("DSFB"), and I am reasonably handy with tools, so I've decided to take a plunge and see if I can actually build a "Chitty Flyer" as a winter building project.

To keep things "simple", I am aiming to build a non-aerobatic, hopefully slow-flying, 2D profile foamie, loosely based on a design I came up with for the Redbull online FlugTag game. This game was really popular with my son and me around 2008, and allowed us to design, test and fly a whole bunch of 2D "flapping wing" models. The screen capture attached will hopefully give you an idea of what I am aiming for.

BTW, you can still play Flugtag online and design and fly 2D at:

http://www.redbullflightlab.com/

I certainly no an aeronautical engineer and I know I am biting off a lot here, so I figured I'd reach out here and see if anyone would be willing to help with this project or even just to give me some tips along the way should I get totally stuck. Thanks for reading and following along!
Altbob is offline Find More Posts by Altbob
Last edited by Altbob; Nov 10, 2014 at 01:18 PM.
Reply With Quote
Sign up now
to remove ads between posts
Old Sep 19, 2014, 01:09 PM
Registered User
Altbob's Avatar
Joined Oct 2012
209 Posts
To get things started, I am collecting some reference material. Here's some reference shots of the actual "flying car" used in the movie -
Altbob is offline Find More Posts by Altbob
Last edited by Altbob; Nov 10, 2014 at 01:19 PM.
Reply With Quote
Old Sep 19, 2014, 01:20 PM
Registered User
Altbob's Avatar
Joined Oct 2012
209 Posts
I'm attaching also a close-up of the profile from my FlugTag "Flight Lab" effort. If possible, I would like to retain the pusher prop configuration, because anything else wouldn't really be authentic.

Here are my initial questions:

1) If the center wing was lengthened a bit, perhaps with an airfoil camber, would it fly?

2) Would the front "winglet"screw things up? Could it somehow be used as a control canard, or to provide some extra lift?

3) Should I "fake it", and have a hinge in the back of the fuselage so that the rear of the car (made from a rowboat in the movie) can act as a rudder - OR - can the rear horizontal stab be given elevons, and fly by bank and yank?

FWIW, I want this thing to be about 3 feet in length so it turns some heads!

Thanks for playing along - hopefully someone out there shares my passion for the movie, the car and the challenge!
Altbob is offline Find More Posts by Altbob
Last edited by Altbob; Nov 10, 2014 at 01:22 PM.
Reply With Quote
Old Sep 19, 2014, 01:30 PM
Registered User
Joined Jul 2004
86 Posts
Grab some FFF or a sheet of depron and make about a 16" profile glider of it. That will allow you to determine the CG and if you need more aft lateral area. You will be able to see if it is possible to get it to fly. Should be possible, have fun, this is what the hobby is all about. The new 3-axis stabilized receivers are amazing and inexpensive. Some dihedral May be needed.
Tcat is offline Find More Posts by Tcat
Reply With Quote
Old Sep 19, 2014, 01:35 PM
An itch?. Scratch build.
eflightray's Avatar
South Wales U.K.
Joined Mar 2003
13,761 Posts
A profile model may just fly as the wing area is very small for anything like a 'full body'.

Some more pictures --- https://www.google.co.uk/search?q=Ch...ed=0CAYQ_AUoAQ
eflightray is online now Find More Posts by eflightray
Reply With Quote
Old Sep 19, 2014, 01:45 PM
An itch?. Scratch build.
eflightray's Avatar
South Wales U.K.
Joined Mar 2003
13,761 Posts
But then, a bit of searching, and --

http://www.flyelectric.ukgateway.net/chitti.htm

Even has the plans for download
eflightray is online now Find More Posts by eflightray
Reply With Quote
Old Sep 19, 2014, 02:03 PM
Registered User
Altbob's Avatar
Joined Oct 2012
209 Posts
Wow, thanks guys! Great and fast responses - the folks here at RCGroups are amazing

With all due deference to the link eflightray (or just "Ray"?), as cool as that plane is, it's not really a very scale profile of the "real" Chitty. Granted that was a full body effort, so the wings and tail had to be a lot bigger than the phantasmagorical car imagined by Ian Flemming, et al. But as a 2D flyer I think we can get closer to the original profile, don't you? I'm sure to crash the heck out of my prototypes, but "up from the ashes grow the roses of success, yes?"

Tcat - yes, a bit of dihedral will be necessary for sure, but I want to keep it to a minimum so I can stay "scale" I assume what you mean by "aft lateral area" are horizontal stabilizers of some kind? I had hoped that the winglet at the back end, using some form of elevon arrangement, might work. Obviously I'm going to have to play around a bit. I don't suppose there is any decent software for this kind of brainstorming, is there? I have Phoenix Sim and Phoenix Builder - has anyone tried that as a virtual testbed for a 2D profile design?

I am going to assume off the bat (knowing very little about quadcopters) that the idea of putting a vertical rotor on the end of each wingtip is simply too fanciful to work. If I'm wrong about that, chime in!
Altbob is offline Find More Posts by Altbob
Last edited by Altbob; Sep 19, 2014 at 02:22 PM.
Reply With Quote
Old Sep 19, 2014, 02:36 PM
An itch?. Scratch build.
eflightray's Avatar
South Wales U.K.
Joined Mar 2003
13,761 Posts
Considering there has been flying go-carts, flying race cars, even flying trucks, I suppose anything is possible, to a degree.

The major problem as I see it is wing area, the scale model just doesn't seem to have sufficient.

The above mentioned flying models use internal surfaces by allowing air to pass through the front, plus the prop is at the front increasing the airflow. Plus they are designed for minimum weight.

It could probably come down to how 'scale' the model needs to be.
eflightray is online now Find More Posts by eflightray
Reply With Quote
Old Sep 19, 2014, 03:18 PM
Registered User
Altbob's Avatar
Joined Oct 2012
209 Posts
Perhaps if I build it as a full fuse plane I can stick an EDF engine under the hood???
Altbob is offline Find More Posts by Altbob
Reply With Quote
Old Sep 19, 2014, 03:28 PM
An itch?. Scratch build.
eflightray's Avatar
South Wales U.K.
Joined Mar 2003
13,761 Posts
Quote:
Originally Posted by Altbob View Post
Perhaps if I build it as a full fuse plane I can stick an EDF engine under the hood???
I think you need some or at least a after that quote.

eflightray is online now Find More Posts by eflightray
Reply With Quote
Old Sep 19, 2014, 03:56 PM
Registered User
Altbob's Avatar
Joined Oct 2012
209 Posts
Quote:
Originally Posted by eflightray View Post
I think you need some or at least a after that quote.

You're right

I am of course willing to fudge the dimensions of the wings and winglets/canards a bit, in the interest of actually being able to fly a pattern with this thing. One thing that is somewhat notable is that the sweep of the wings was a little less on the car designed for the stage play vs. the movie. I think I can push this a little further and still look relatively authentic.

http://movi.ca/im/mio/chittybangwp1024.jpg
Altbob is offline Find More Posts by Altbob
Reply With Quote
Old Sep 21, 2014, 07:11 PM
Damn this gets addictive.
Thechittyfather's Avatar
United Kingdom
Joined Oct 2011
530 Posts
Good choice. Hope you have success with this I'll be keeping an eye out.

I chose my handle because my first build was a chitty. I basically built a simplified version of the car out of foam and modified a EZfly to drag it around. Gave it a paint job with all the non chitty bits left white and it looked pretty cool in the air. I will attempt to upload a photo.
Graeme (tCF)
Thechittyfather is offline Find More Posts by Thechittyfather
Reply With Quote
Old Sep 22, 2014, 09:55 AM
Registered User
Altbob's Avatar
Joined Oct 2012
209 Posts
Nice work Graeme!
Altbob is offline Find More Posts by Altbob
Reply With Quote
Old Sep 22, 2014, 10:38 AM
Damn this gets addictive.
Thechittyfather's Avatar
United Kingdom
Joined Oct 2011
530 Posts
PS. Don't make the same mistake I did. I gave it working wheels but set the wing at 0 incidence to the wheels which made for very fast take offs. Funny watching it zoom around the field though.
Might have been made worse because I used a Kfm airfoil. Something with more lift might be ok.
Thechittyfather is offline Find More Posts by Thechittyfather
Reply With Quote
Old Sep 22, 2014, 01:11 PM
Registered User
Altbob's Avatar
Joined Oct 2012
209 Posts
Yeah, I want the smallest possible wing loading - this thing shouldn't fly all that fast. That's why I am thinking a 2-D foamie could be best.
Altbob is offline Find More Posts by Altbob
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Bang Bang! Bang Bang Bang! Bang Bang Bang Ping! logan5 Life, The Universe, and Politics 42 Apr 01, 2014 10:29 PM
Discussion Chitty Chitty Bang Bang Heading to Auction MtnGoat Life, The Universe, and Politics 18 Apr 27, 2011 02:12 AM
Himax/Phoenix25 goes like "Chitty Chitty Bang Bang" cabbie Power Systems 10 Oct 03, 2004 12:55 AM