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Joined: 11/30/2003 From: Cadillac,
MI, USA Status: offline
There was a big review of this model in the July "Model Aviation". Prior to this, the Seawind showed "discontinued" on the Tower website. Now it's in stock.
The author spent a lot of time describing exactly what must be done to take off, not so much properly as AT ALL, rather making dumb circles around the lake.
My opionion: it's a piece of s**t, and Tower hired some pros to figure out how to fly it and lie about how great it is.
There was a big review of this model in the July "Model Aviation". Prior to this, the Seawind showed "discontinued" on the Tower website. Now it's in stock.
The author spent a lot of time describing exactly what must be done to take off, not so much properly as AT ALL, rather making dumb circles around the lake.
My opionion: it's a piece of s**t, and Tower hired some pros to figure out how to fly it and lie about how great it is.
Bob, I never owned the Seawind, but after looking at the model and then watching struggles most of modelers have during the takeoffs, I came to conclusion that one of the problems is the shape of the wingtip floats. I do not have three view of the full size Seawind, but looking at the photographs of full size I can see that the model’s floats are not deep enough and even the angle of bottom of the float is too shallow. The extremely sharp leading edge of the wing at the point where the tip float starts does not help ether. The electric foam version of the Seawind has different shape and it perform much better during the takeoffs. These are my two cents. Laddie.
Posts: 1199
Joined: 11/30/2003 From: Cadillac,
MI, USA Status: offline
Thanks, Laddie.
I think I read either earlier on in this thread or someplace else about people making tip floats for this airplane, because of takeoff difficulties.
The coincidence of the re-release of the aircraft and the big, obviously promotional article in MA cannot be ignored. Tower has a proven record of sticking with bad designs long after they have been universally condemned by the customers. The Lanier "Seabird" comes to mind. This behavior from an otherwise good company that provides many successful products. Go figure. My guess would point the finger at the accounting department.
Posts: 53
Joined: 9/4/2004 From: Playa del Rey,
CA, USA Status: offline
Greggk,
When I said I put in the soda pop can to balance the model, I am adding the equivalent of 12 oz of fuel in the pylon whereas the model has a 14 oz tank. I then use the cg when balanced with this technique to be reference point for where I want the model to balance when I place it in the water. To be complete, I started by balancing the model with the cg at 1 1/32 " with everything, including batteries, in place. I then put the soda can in the pylon to see where the cg would be if I was flying with 12 oz of nitro fuel. I remeasured the cg and found that with the soda can in place the cg had moved back to 1 5/8". I then removed the soda can and rebalanced the model so that the cg moved to 1 5/8" by moving the batteries to the rear in the fuse. I feel that 1 5/8" is reasonably conservative since most nitro models take off with a full tank, so when the model is balanced a 1 1/32 dry per instructions, that is the equivalent of taking off with the cg at about 1 7/8" behind the leading edge when the tank is full of fuel. As the nitro model burns fuel, the cg moves forward. If you run the tank dry, then the cg is at 1 1/32 when the plane lands. With the electric version, the cg doesn't move. I prefer the control feel with the cg at 1 5/8. It also makes takeoffs easier. If you feel uncomfortable starting with the cg that far to the rear, start with it more forward. But if the model begins to porpoise a lot on takeoff, start to move the cg back. In your case, you also need to be careful with the application of power; the setup you describe probably has enough power to make the plane do cartwheels. Apply power slowly and make the takeoff run as long as possible.
Posts: 546
Joined: 6/2/2003 From: Guelph,
ON, Status: offline
Hmmm, my seawind is stock and I have little problem taking off and landing on water? CG, wingtips and step location are all unchanged. Maybe power is the issue I do not know. My engine is an enya 60 which is not all that powerful, probably close to an OS 55AX.
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Joined: 9/4/2004 From: Playa del Rey,
CA, USA Status: offline
RVman,
Are you taking off with the stock tank filled? If so, then your Seawind is balanced about 1 7/8" when filled with fuel (assuming it was set up dry per tower instuctions with the cg about 1 1/32" behind the leading edge). Also, you are not overpowering the model. What prop and what rpm do you have on takeoff? Glad to hear things are going well for you.
Posts: 546
Joined: 6/2/2003 From: Guelph,
ON, Status: offline
yep the tank is full at takeoff, I balanced at 1 1/32 with an empty fuel tank like the instructions told me. Not sure what the balance is when the tank is full though. Prop is a 12-8 masterairscrew K series 2 blade and rpm is about 10500 - 11000. I am taking the plane out tommorow to go float flying, maybe i'll try to get video.
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Joined: 9/4/2004 From: Playa del Rey,
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Hi,
For those of you who don't yet believe in electric Seaplanes, I've posted my latest Seawind landing on youtube. It can be accessed via the link "www.youtube.com/watch?v=JC9iOqEJU00".
I'm running an AXI 4120/18 turning a 12x12 apc. Power is a 6s1p battery pack at 3200mah. I'm also using a Jeti 70 opto esc.
The video was shot in the SW corner of Lake Tahoe near Lighthouse shores with Mt. Tallac and the Desolation wilderness in the background. Note that the altitude here is 6250'.
Posts: 6
Joined: 7/5/2007 From: Ridgefield, CT, USA Status: offline
quote:
ORIGINAL: RVman
Hmmm, my seawind is stock and I have little problem taking off and landing on water? CG, wingtips and step location are all unchanged. Maybe power is the issue I do not know. My engine is an enya 60 which is not all that powerful, probably close to an OS 55AX.
I get to fly my GP Seawind in the summer when we go to our vacation spot. We are near Gananoque, Ontario in the 1000 Islands. So far this year I am batting .666 with 4 successful takeoffs from water for 6 attempts. After the first flying session I was only 1 for 3 and feeling very frustrated until I went back and looked up the GP Seawind posts on RCU. There was enough success reported there to make me consider carefully how to continue. Also, conditions have been nearly perfect: calm, clear and sunny.
With the benefit of everyone’s experience I was able to proceed more calmly than I might otherwise and take things SLOWLY. I used what has already been reported here:
1. Take off directly away from my position, so I can see the aircraft roll axis very clearly. 2. Throttle up slowly; the plane porpoises when it gets on the step but then this damps down. 3. Then go to full throttle; the plane will porpoise or bounce into the air before flying speed is reached. There is enough time to level the wings and control the next bounce without throwing the nose up and causing a stall. On my fourth takeoff only 2 bounces were required to get airborne(compare to the takeoff video I posted last year, http://www.rcuvideos.com/item/H2C1YL0GNVS6KSY0, which has a lot of bounces).
Once in the air, the Seawind flys on rails. Landing is the reverse of take off with more bounces - a smooth touch down ends up in higher and higher bounces(a video of two landings and one takeoff is posted at:http://www.rcuvideos.com/item/4R4GMGX7JJ8PMTWG).
You can see the problem the Seawind has most clearly if you examine the second landing on my most recent video (http://www.rcuvideos.com/item/4R4GMGX7JJ8PMTWG) one frame at a time. During the second bounce, as the Seawind touches down on the water its angle of attack is flat, nearly 0 degrees, then as it rises out of the water, its angle of attack has increased to ~thirty degrees. Unless the plane is re-leveled before the next water contact, disaster is imminent. The same increase in the angle of attack as the plane bounces on the water shows up on takeoff. It has been proposed here on RCU to put aileron stock on the hull behind the step to stop the porpoising. Before my most recent flight, I did this but I didn’t detect a big change in the porpoising behavior - I will have to try it more. Another thing that might work would be more stabilizer area. The present stabilizer is OK for high speed flight, but more area should “stabilize” the porpoising as flying speed is approached on a water takeoff.
My Seawind is showing cracks from its adventures and some of the inside framing is probably detached from the fiberglass(~15 takeoff attempts). I’m using an old OS FS91 with a 12 x 8, 3 bladed Master Airscrew. There is a prop cut in the fuselage below the blade arc from all the bouncing/porpoising. I usually have 1.0” or more of water in the hull bottom after a flight (mostly from around the sealed up bailer).
So, like many others here, I wish GP would address the problems with the Seawind with a Seawind II, or at least a sheet with suggested mods, but in the meantime I’ll keep on taking my chances.
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Joined: 12/30/2001 From: Burbank,
CA, USA Status: offline
Tony: I notice that you are an AMA member. You might want to read the article on the Seawind in the latest issue of Model Aviation. The takeoff and landing techniques described there have worked well for myself and many others. (No bouncing is involved.)
That article was straigh on. I flew mine for 2 summers and now have decided to get out of glow. Converting the Seawind would cost a ton plus I don't have that much access to water so mine's up for sale. Magnum .91 with all the servos and Robart retracts. I live in Wisconsin, near Milwaukee so if you know anybody that would be interested, have them PM me. Paul
Posts: 35
Joined: 3/31/2007 From: , MI, USA Status: offline
Phew! I finally got to the end of reading all this thread while at the same time (over the past week) building my electric GP Seawind. Gregg, I'm going for a CofG of 2¼ inches behind the LE, this is based off the info on the other thread about electric conversion. I am using a Turnigy 50-55-400 motor and 4 x 1800 3S LiPOs in a 6S2P configuration giving the equivalent of 3600 6S1P. I only have a set of bathroom scales here on the lakeside cottage (we're at our summer home) and when I put the fully set up Seawind on the scale it says 9 lbs so I'm guessing close to or slightly under 10 lbs AUW. I am using a MA 13x8 2 blade prop (only one I could get locally) and that gives me only 650W max on static run tests (the recommended 3 blade 11x7 pulled only 540W); I would have liked more but like Norm has been saying all along, more is not necessarially better on this bird(fish). I got as far as serious water taxiing tests yesterday; all went well and she almost lifted off with a few bounces off the wave crests. I can clearly get her to plane on the step no problems and I'm nowhere near full power. I caught the rudder on a rock which bent it into the fuse but it bent back OK and there's no servo damage. I got a suprising amount of water in the plane and I'm investigating where that got in although it was kinda choppy yesterday when I did the test runs.
Weather here is gusty with showers this morning so no maiden for now, I'm going to investigate the possibility that water is getting in around the rudder tube.
Been practicing on the Alpine Lake in Realflight 4.0.
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RE: Great Planes Seawind - 
