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Archive for January, 2012
Posted by twinkle | Jan 31, 2012 @ 09:53 AM | 7,623 Views
Many years ago a young Chris Foss the man behind Chris Foss Designs apppeared on the local slope clutching his new design a solid wing balsa rc glider with 2 channel radio control . That must have been in the mid seventies at 6ft span (1.8metres )with its narrow wing the aspect ratio was 18;1 it became a great success and was kitted by micromold a local company
with its original 6mm thick wing, it flexed and how and the mk 2 model appeared on the slope with a 10mm thick wing carved from 100mm x 900mm balsa sheet with a spruce spar. Now over 30 years later I decided to build my own from what I remembers of the original and a few modifications ofcourse.
Here it is modified and brought into the 21st century with flapperons and just a hint of dihedral with 4 servos and rx and a 900mah nicad it weighs 24 ozs. The wing loading coming out . You guessed it to 12oz sqft its great in most conditions
and we use it to go for a walk along the downs ( some call it crosscountry)
the nicads give a good hour in flight and the upward deflections of the flapperons
kills the lift for a landing steeper appoach . it looks nice in the air and although the wings have a little flex in them, they haven't broke yet
finished in doped tissue with a little trim , it looks the business in the sky
The high aspect ratio wing adding to it's grace .
Posted by twinkle | Jan 30, 2012 @ 02:52 PM | 7,229 Views
Here are the photos of the Jackal and Jeckel together to show their main differences
although the span is similar te Jackal has a constant chord wing with tapered ailerons where the Jeckel has a taper wing with constant profile ailerons .
Both twins are powered by the CF2812 motors with 3s1p 1800 Lipos and 20amps escs almost 3lbs of thrust and 250 odd watts of power using 8x4 counter revolving props. the Jeckel has an extra servo for the flap. .Both weigh almost 1kg and the wing loadings are 12oz/sqft
In Flight the characteristics are similar the built-in undercarraige of the jeckel make the model sit lower but still has enough ground clearance to take off and land on grass .Both models need to be flown "to the ground " The trike u/c gives good ground handling and both models get airbourne in a short distance and have plenty of power for aerobatics . The jeckel with its hugh booms has that transporter look and it is agile and was not affected by cross winds .

Getting the wiring into the jeckel was no joke with 3 extension leads going to each boom and power cable of 20 amp rating there was not much room in the centre of the wing and the weight of the wing doubled with all that copper.
the jeckel is very much a one piece model although it will come apart for servicing I have a boom brace which stops any twisting when the wing has been removed