Great Planes Seawind EP Tip Float Modification and Mini Review
Posted on July 8, 2008 by aaronredbaron
I received my Great Planes Seawind EP floatplane for my birthday in November 2007, and quickly had the airplane flight worthy. I didn’t have a chance to test fly it for some time until I moved home to Oregon, and when the chance came up this spring, I went to my old float flying spot on the Willamette river. I have been float flying at a spot at the Cedar Oak boat launch in West Linn for years. The airplane flew great but had a nasty habit of grabbing the wingtip and ground looping (spinning around during takeoff on the ground or in this case, in the water), and after a quick search I found a thread on RCgroups that confirmed my results. After a brainstorming session, I came up with a modification that practically eliminated the problem and made the airplane a dream to take off and land, with virtually none of the problems it used to have.
Modification: Add a step to the Seawind wingtip
Tools: Sharp hobby knife, and foam-safe clear sealant
My idea was simply to add a step to the tip float. I cut along the trim lines on the bottom of the tip float, and trimmed approximately 1/4 of an inch off the bottom of the tip float from the trailing edge up to the step. Make sure to use a very sharp hobby knife to cut the foam cleanly. After trimming the same amount from each wingtip, spray the exposed area of foam with a clear, foam-safe sealant. The final step it to re-balance the airplane laterally.
After the modification the model was capable of digging the wingtip in the water without grabbing. I now use the ailerons to push the wingtip into the water to make controlled, sharp turns on the water. At speeds from slow to fast, the model behaves predictably on the water. It must be slowed down below planning speed before it will turn in the water.
Wing Bolt: for some reason, the kit came with a blind nut in the fuselage, and a self tapping screw for the wing bolt. Be sure to replace the wing bolt with a machine screw that threads cleanly into the blind nut. I believe the blind nut has a 3mm thread.
Takeoff and Landing: Hold some up elevator during taxiing and takoff run. Hold a small amount of up elevator the entire time until the airplane breaks ground and then slowly let off the elevator. On landing add some up elevator in during the flare, and continue to hold that elevator input as the model settles in and slows down on the water. If done right, adding the elevator during takeoff and landing will eliminate any porpoising that may show up. Some people on the forums had changed the thrust angle to eliminate porpoising during takeoff. I found that the model did not need any thrust angle adjustments in flight, and I prefer the elevator procedure to altering the thrust angle because the airplane already flies nice and neutral. In fact, it is the first top motor mounted float plane I have had that does really well upright and inverted.
