Tim Hooper Posted May 4, 2011 Share Posted May 4, 2011 Evenin' all! This is probably very premature, but I've had this idea knocking around in what's left of my brain for a little while now. Trouble is, it's not scale. Scale is easy - the full-sized designer has done all the hard work, whereas a non-scale sports model has to be done from scratch. Truth is, I've only ever designed one non-scale model before, so I'm a bit nervous. So here we go. I fancy something a bit whizzy, but employing a swept-forward wing, some fancy down-turned Hoehner wing tips, and a T-tail. So out came the graph paper and a stub of a pencil. Doesn't look to bad , I was encouraged to quickly build a 17" chuckie to see if my CG calcs were in the ballpark.... I set the CG at 25% MAC, and suspended the chuckie from a wire hook whilst I added a little bit of nose weight. So far, I'm delighted to report that the little chuckie flies well!tim Edited By Tim Hooper on 04/05/2011 23:08:05 Quote Link to comment Share on other sites More sharing options...
Tom Wright 2 Posted May 5, 2011 Share Posted May 5, 2011 Now that does look good Tim how about making this one say 60 in span with a wing loading of no more than 20 oz per sq ft ? the modest wing tapper and dihedral could result in a really nice sports design that is different and easy to fly ,what do you have in mind EP or the dirty option? Oh glad to see its got an elev rather than the tempting all moving alternative. Tom.Edited By tom wright 2 on 05/05/2011 00:17:40 Quote Link to comment Share on other sites More sharing options...
Stephen Jones Posted May 5, 2011 Share Posted May 5, 2011 Hi tim Get it done it looks good too me . Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted May 5, 2011 Share Posted May 5, 2011 Looks brilliant Tim - positively unique! What sort of size were you thinking of? Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted May 5, 2011 Share Posted May 5, 2011 Hi TimStarting literally from a blank sheet of paper is an interesting exercise. I like your approach of building a 'chuckie'. In an unusual design it certainly allows you to get an idea of the CofG. Was there any reason for the sweep forward?From a structural point of view it needs careful design to ensure that any flexing under load does not increase the angle of attack towards the tips. This can be a receipt for disaster in a high G situation! You would never think you put the span in the title! Edited By Simon Chaddock on 05/05/2011 10:13:53 Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted May 5, 2011 Share Posted May 5, 2011 Looks great Tim, nice lines and looks well proportioned if a little short on tail moment. 60" with a 1kw motor should make it shift.......... You could design some fancy Hoehner tipped bicycle clips to go with it Should be fun well done for having a go CheersDanny Quote Link to comment Share on other sites More sharing options...
Tim Hooper Posted May 5, 2011 Author Share Posted May 5, 2011 Cheers lads! Simon, I hear you on the inherent wing flex issues. I've done a bit of research (read 'Wiki') on the subject, so I'm going to build in a couple of degrees of washout. Hopefully I can build a stiff enough wing for it not to be needed though! The forward sweep is for pure aesthetics really, but it tends to drag the apparent CG forwards, so the long nose should help to negate the need for any ballast up front. That's the theory anyway! Tom, I'm sort of partial to the 48" span idea. I have my 'known' 450 watt, 3S power train in mind (and in stock). Not only that but 48" is about right for any freebie plan later on.... tim Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted May 5, 2011 Share Posted May 5, 2011 Looks lovely Tim, I like the 48" size. The nose cheeks look like they will set it off a treat too. How about a V tail? (only joking the T seems to suit it). Cheers Chris Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted May 5, 2011 Share Posted May 5, 2011 48" is perfect Tim with that power train in mind. All you need to do now is to educate the readers into actually reading the thread title properly! Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted May 5, 2011 Share Posted May 5, 2011 Quote Link to comment Share on other sites More sharing options...
Tom Wright 2 Posted May 5, 2011 Share Posted May 5, 2011 OK Leccy i should have gone to spec-savers. . Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted May 5, 2011 Share Posted May 5, 2011 I actually meant ME guys, not you! Quote Link to comment Share on other sites More sharing options...
Tim Hooper Posted May 5, 2011 Author Share Posted May 5, 2011 Posted by leccyflyer on 05/05/2011 16:15:39:48" is perfect Tim with that power train in mind. All you need to do now is to educate the readers into actually reading the thread title properly! So, that's an hour in the Naughty Corner for you, young Brian! Quote Link to comment Share on other sites More sharing options...
Steve Adams Posted May 5, 2011 Share Posted May 5, 2011 Kinda reminds me of Terry Eatos Freebird,featured in RCM+E in the early 90s.Got some hints of John Rutters designs in There as well! Looking forward to this one,its nice to break the mold,once in a while,showing your wild side now Tim.A hearty Congratulations to you sir! Quote Link to comment Share on other sites More sharing options...
Tim Hooper Posted May 9, 2011 Author Share Posted May 9, 2011 Thanks guys! I've unleashed the crayons upon an unsuspecting sheet paper and this is the result so far; That big black bar is a 24" ruler to give a bit of scale to the proceedings. AS the model looks a bit boy-racerish, I've opted for a 10% aerofoil to minimise drag a little, then printed them out via Profili. I'll draw in the spars manually later.... tim Edited By Tim Hooper on 09/05/2011 14:53:17 Quote Link to comment Share on other sites More sharing options...
Tom Wright 2 Posted May 10, 2011 Share Posted May 10, 2011 Tim .You have just demonstrated why i am so reluctant to submit designs and plans for publication ,i am not artistic and can only draw straight lines . Even you prelim work is .........so good ! Do you have the weight and wing loading projections yet ? the motor selection suggests weight at around 4.5 LBS. Grrr Tom.Edited By tom wright 2 on 10/05/2011 01:03:13 Quote Link to comment Share on other sites More sharing options...
Tim Hooper Posted May 10, 2011 Author Share Posted May 10, 2011 Hi Tom! Thanks for the compliments, mate. I'm not particularly artistic either - but I've been around long to develop a feel for the TLAR quotient of an airframe. TLAR stands for 'that looks about right'........ The wing area has come out to 364"², and power system I've earmarked is a favourite, known system - Turnigy 35/42 1250Kv, 9x6 prop and 3S 2700 li-po - that pulls a measured 450 watts. This is the same system that I use in the 49" Seagull PC9, and my own 56" Airspeed Courier. Both of these models weigh well under 3lb, so I'm hoping the Clean Sweep will be in the same ballpark. So no shortage of power then. tim Quote Link to comment Share on other sites More sharing options...
Tom Wright 2 Posted May 10, 2011 Share Posted May 10, 2011 Tim Thanks. I tend to follow your designs as generally the wing loadings are low making it practical for a wider range of pilots and terrains , if a model is pretty or even scale it does not have to be heavy and that's were the structural engineering comes in to the design equation, you might have gathered i don't like " pretty bricks" much, but i do appreciate your ability to combine good looks with low weight. Tom. Quote Link to comment Share on other sites More sharing options...
Lindsay Todd Posted May 10, 2011 Share Posted May 10, 2011 Very nice Tim, bit Reno Racer ish, would make a good club 20 pylon at that size, mmh there's an idea? Linds Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted May 10, 2011 Share Posted May 10, 2011 Mass build racers for next year ? Quote Link to comment Share on other sites More sharing options...
Stephen Jones Posted May 10, 2011 Share Posted May 10, 2011 Hi Tim , Looks great, looking forward to this one coming along , I still fancy myself as a bit of a boy racer Quote Link to comment Share on other sites More sharing options...
David Ashby - Moderator Posted May 11, 2011 Share Posted May 11, 2011 Looking good Tim, I just love that Cosmic Wind, Midget Mustang racer style aircraft. Quote Link to comment Share on other sites More sharing options...
Ton van Munsteren Posted May 11, 2011 Share Posted May 11, 2011 I like that T-Tail Tim. Ton Quote Link to comment Share on other sites More sharing options...
Tim Hooper Posted May 11, 2011 Author Share Posted May 11, 2011 Thanks Guys! Your encouragement really is appreciated! No progress today - had other models to work on - Netty finally discovered how to upload pics from all-singing, all dancing phone, so here's one of the chuckie on it's way skywards! tim Quote Link to comment Share on other sites More sharing options...
Big Bandit Posted May 12, 2011 Share Posted May 12, 2011 Hi Tim, That's really inspirational and looks just right. It gives the idea to budding designers on how to start and progress with OD models. Cheers, Chris. Quote Link to comment Share on other sites More sharing options...
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