GULL II
Comet designed this freeflight bird that has grown up to be an excellent electric R/C model!
By Pat Tritle I 38
built the first Comet Gull II some- where around 1969 from the orig- inal Comet kit. The model was covered with the kit supplied tis-
sue and painted with dope in a very flashy red, white, and blue sunburst scheme, and no doubt weighed a metric ton! The model never flew, but hung around till about ten years or so ago, slowly rotting away till it finally fell completely apart. Then a few months ago I built anoth-
er one from a more recently produced Comet kit converted to 3-channel R/C, but it was so heavy that it flew poorly. So I decided it was time to blow it up to a 50-inch span and design it specifical- ly for electric power and 3-channel R/C. These old F/F designs make excellent subject matter for these enlarged de- signs, and always seem to fly very
well—and in that vein the Gull II has proven to be no exception. The design began by photographing
the plans from directly above with a digital camera, then loading the image into AutoCAD and tracing the outlines. As much of the original construction style as possible was retained, includ- ing the lifting stabilizer, to produce a close likeness to the original model. However, the wing was redesigned us- ing an egg-crate style spar and turbula- tor spars with ply dihedral braces, and the rib spacing was changed to elimi- nate eight ribs in an attempt to keep the flying weight down. The airfoil was also changed, using the undercambered sec- tion from the original Dallaire Sport- ster. This is the third design I’ve used this airfoil on, and it has proven itself very well in all three attempts.
AT A GLANCE Type:
Construction: Wing span: Wing area: Length: Weight:
Wing loading: Prop:
Motor: ESC:
Battery: Radio:
R/C sport
balsa and ply 50 inches 363 sq. in. 42 inches 13 ounces
5.2 oz./sq.ft. 9-4.6 GWS
Tower Pro 2208/17
Common Sense RC Z-20 1600 mAh 2S Li-Po
Spektrum DX-7 w/AR6000 Servos: two 9-gram sub-micro servos DECEMBER 2011
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