Bird of Time
BIRD OF TIME 2011
Bird of Time is one of those models that when you see one you want one. Designed way back in the late 1970's by Dave Thornburg it was first published as a free reduced scale plan in the January 1979 issue of Radio Control Models or RCM. (USA) Designed as an Open Class 118" tow line sailplane, it seems to have had a renaissance of late with a Balsa Kit & an ARTF Fiberglass Fuselage version by Dynaflight (mentioned in a recent BMFA magazine, Oct 2011 pg. 11) Both kits are imported by Ripmax and sold thro' the usual Model Shop network. Kits pop up on eBay from time to time but with a good plan the kit is rather a luxury, although the fibreglass fuselage version sounds interesting. It will fly in more or less any wind from a light breeze to a near gale and makes an ideal large slope soarer. The wing looks a bit like a Minimoa, but construction is quite straightforward and makes an ideal winter project, even though it is a large model costs should be very reasonable, apart from the covering materials !! One problem with these large "floaters" is getting them down in one piece, especially on a windy slope field. This model is best fitted with spoilers in the middle of the top center sections. With the advent of LiPo's, an electric in-runner and a folding prop you can make life a lot easier if the wind drops or you are too far downwind on finals. With judicious use of the motor you can fly all day on a 2 cell LiPo. Another good idea is a standard NiMh reserve 4.8v Rx battery, if the LiPo runs out, the reserve auto kicks in and although you are without the motor all other functions operate normally, and it could save you a fly-away. (Battery Backup Circuits) The original had a two piece wing with a c/l joint, but any number of options are available from a two piece wing to a four piece. A quick search of the Internet will find plenty of "blow by blow" build notes and photo's, I did however struggle to find a copy of the original plan, fortunately a friend has a complete set of RCM, so straight from the original 1979 RCM article here it is. My apology's to Dave Thornburg & RCM but after 32 years I am sure it is well out of copyright. Photo' & build notes to follow. The .pdf file is large so be patient, overall size is 62" x 37.00", there is a scale ruler calibrated in inches located in the bottom right-hand corner of the drawing. Weight comes out at approx. 3lbs 12ozs for the non electric & 4lbs for the electric version.
If you do decide to build the electric version it is a good idea to buy the motor/spinner and folding prop unit first, make the front of the fuselage the same diameter as the rear of the spinner, and the internals a suitable size for your chosen motor. Motor & ESC details to follow. Do watch out for the VERTICAL GRAIN on the wing spar webs.
You will find below a reprint of the original RCM Article of 1979. It givesa rare insight into the thoughts & trchniquese of the Free Flight Scene in California circa 1979. Very interesting article.
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Bird of Time |
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Text © Colin Usher 2011 Illustrations © Colin Usher 2011
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