When it comes to thinking really big, Model Airplane News contributor and giant scale guru, Carl Bachhuber can usually be counted on to come up with something truly amazing. Producing one of these modeling monsters takes a surprisingly short period of time for Carl and his newest project, the Convair 580 airliner took him only six months to build. We caught up with Carl to get the inside story on his amazing airliner. Here’s what we learned.
Carl, you come up with these colossal projects on a pretty regular basis, tell something about the process for your Convair 580.
I started working on the project in September 2011 enlarging Don Smith’s 132-inch span Convair 440 plans. I also modified the drawings as the nacelles needed to be redrawn to simulate a Convair 580 or Canadair CC-109 Cosmopolitan. Canadair was a Canadian subsidiary of Convair which manufactured the plane as a VIP military transport. Actual building began in October, 2011 and continued through April of 2012. So it took about 8 months from drawing to first flight.
Video by Rich Behrend
What about the construction method and hardware?
The model is constructed primarily of lite ply and balsa covered with fiberglass cloth and epoxy. Most of the molds for the formed fiberglass parts were made using various silicone rubber molds depending on the number of parts required to get the parts off of the plug master. The plane uses 18 Hitec servos and is powered with two of Horizon’s Evolution 80 engines turning 22×10 4-bladed props. The radio is a Futaba 12FG 2.4GHz. The wheels and brakes are from Robart Mfg. The landing gear was designed and built by my good friend Bob Walker the retired founder of Robart Mfg.
Is there anything special, besides the span, in making such big wings?
No, not really. The wings are built up in typical balsa and light-plywood fashion using balsa and basswood front and rear spars. The outboard wing panels are attached with an aluminum joiner tube which slides into a mating aluminum socket tube. The Cosmo spans 200 inches and with a fuselage length of approximately 156 inches the plane is about 16 percent of full scale. Weight is 105 pounds.
What about its beautiful finish?
Having some great Canadian friends required me to use the Canadian CC-109 Cosmopolitan Canadair livery. The plane is prepared just like you were going to paint it with fiberglass cloth and resin and lots of sanding and priming to produce a smooth surface. However, instead of silver paint, I use a polyester mylar product used by sign makers called “Orafol” which comes with a bright chrome color finish. It has an adhesive backing and I apply panels of the material to replicate the look of the polished aluminum finish of the full-size airplane. The material also accepts painted trim nicely and I used Krylon spray paint but most anything can be used.
How does the Airplane perform?
Being 105 pounds it does fly with an AMA waiver. The plane performs fairly well with the Biela 22×10 4-bladed props however, landings are another matter. I have had several embarrassing landings where the very effective Fowler flaps and 4 bladed props have very quickly slowed the plane to a stall situation. My “expert” handling of these situations has resulted in the replacement of several expensive 4 bladed props and broken gear mounts. I hope to improve my piloting skills after a brain transplant! There is a YouTube flight video and more pictures on my webpage carlb-rcplanes.com/Convair580.html. One other special feature that usually garners a few chuckles is the aft side door opening and a Royal Canadian “Mountie” who makes an appearance after landings waving his hat and a Canadian flag.
Text by Palmer Johnson PHOTO CREDIT: Palmer Johnson & Carl Bachhuber