After flying my little flying boat, I decided it flew so well that I would build a bigger version but as a twin, as the fuselage from the original plan I used is based on the grumman goose, which is a twin. I am going to call this one Snow Goose, cos its white. 😁 My small version had a flat bottomed hull, I wanted the proper V bottom hull profile this time, so a lot of redesigning had to be done, as well as enlargement. I chose 1.5 x for the twin, giving a couple of inches under 3 feet, so I extended the wing till it was 3 feet. Not a great amount extra but it all helps. The reason I chose the 1.5x enlargement was that the two fuselage sides just fit on a sheet of 2mm depron at this size. Power was to be provided by a pair of Syma X7 quadcopter motor and gearbox units, These became available when my friend crashed the quadcopter and somehow killed the board , the motors are all fine and low flying time on them as well so they are nice and quiet.
The motors were the main reason for starting the snow goose, and they have proved to have planty of power, coping with the drag from the 60mm wide and very deep fuselage. Most of the construction is 2mm depron with bits of 1mm, 3, 6 and 9mm in areas that needed it. 2mm carbon tube leading edge reinfocement on wings is just taped on with thin strips of sellotape. A small section of 1mm carbon on trailing edge centre protects the depron from the wing bands. There is a lot of depron up front, for support and bits to allow shaping. The battery bay is pretty tough to stop the battery bursting through in a 'heavy landing'. I tried keeping the rear end as light as possible, using 1mm depron on the top and on the bottom, I was hoping to use 2mm depron for the tailplane and fin but it was just too wobbly so 3mm was used and works perfectly. When it came to balancing the plane, I had to use a 20.4 g 750mah cell, pretty much the one I had thought about using, I made the battery bay big enough to take a range of batteries. 20 grams is a chunk but 2 motors would use more power. Anyway, loaded up with this battery, Snow Goose is 108g, my heaviest build using the F949 board, and my first twin using it. Actually, this one uses an 8g F949S board, same idea but slightly bigger servos and switchable gyro. Nice feature which smooths out flying for a nice scale like appearance. It only works with F949S transmitter bit thats ok because I bought the F949S rtf plane, which is an excellent little plane by itself and lets me fly the Snow Goose using its transmitter. Its got decent radio anyway, basic, no servo reversing, end point adjusting or fancy mixes here, good range and a decent feel make up for this. The first glow engined planes I flew years ago used radio with no reversing, you just have to arrange things to suit. Anyway the boards are £12, so well worth the slight effort of having to think about control directions beforehand.
The wing floats and motor pods are easily detachable.
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Topic: Snow Goose flying boat (Read 1570 times)