| Power Planes |
ModelTech Great Lakes Biplane |
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This plane belongs to a friend. I test flew it for him. All in all, this seems like another well make kit/ARC from Model Tech. It has a few quirks, but it flies very nice.
The main points...
1. It builds very tail heavy. Either use a heavy engine (like a 4 cycle), or move the engine forward.
2. Take offs are not as easy as some tail draggers, but they are not scary. The plane showed no tendancy to do any sort of violent tendancy to ground loop or swerve, but you definitely need to use the rudder to keep it straight. If you advance the throttle smoothly and let the speed build gradually, you should have no problems.
3. Flying: It seemed to fly very nicely.
4. Deadsticks I didn't get much time to evaluate the flying as the engine went dead stick on both the flights I made. This thing is really draggy, so keep the descent angle fairly steep. The speed with bleed off very rapidly as the nose is pulled up. There didn't seem to be any tendancy to tip stall. I was able to put the plane on the runway both times, so there was no damage.
The flight...
This plane is my friend's his first tail dragger, and on his initial attempts, he had no luck getting it off the ground. Apperently it was too squirrely for him. Anyway, he asked me to take it off and trim it out for him.
We got to the field around 3PM. It was overcast, and there was a light breeze blowing right down the runway. I was really dreading the take off. I once had a Midwest Sukhoi .40 that was a bear to get off the ground. I'd feed in some right rudder to correct the for the torque, and the thing would swing vioently to the right, then I'd try to correct the other way, and it would swing quickly to the left. Usually, it ened up pointing 90 degrees to the centerline of the runway. I feared that the Great Lakes would be similar.
I lined the plane up on the asphalt runway, and very graudally brought the power up. As it gained some speed, it did get a bit squirrely. I definitely had to steer it with small amounts of rudder in both directions at this point, but there didn't seem to be any tendancy to veer off hard in either direction. Soon after, it stabilized, and I added more power power and took off smoothly.
After giving it about 2 clicks of left aileron trim, the plane flew very nicely. It flies very smoothly and seems to have somewhat neutral stability. I circled the field a few times at half throttle. The plane has an Magnum (ASP) .46 in the nose, and it moved around at a pretty good speed at that setting. At full throttle, it didn't really seem to go much faster, but then it is a pretty draggy design. I did notice that it wanted to climb when full power was applied. Possibly there wasn't enough down thrust.
I handed off the transmitter to the owner, and not fifteen seconds later, the engine quit. He handed the transmitter back to me and I setup for landing. At first it seemed that I was going too fast, but it became readily appearent that this thing bleeds off speed quickly!. I had enough altitude to do a fairly normal, albeit somewhat steep, approach. It seemed to require quite a bit of up elevator to flair. Whether this was because the plane was nose heavy, or because there was less elevator travel then I'm used too, I can't say. Once I started feeding in the up elevator, though, it flaired out okay, and settled into a halfway decent landing (okay, I landing half in the grass, half on the runway, but other then that, it was okay).
The Magnum doesn't seem to run very good at anything below about 3/4 throttle, so we figured that that was why it died (it also doesn' t, idle very well, btw). After refueling, we put it on the runway for the second flight. This time the take off was perfect (if I don't say so myself). Again, I very gradually put the power on. It requried just a touch of right rudder about halfway through the TO roll, but it quickly stabiliized and I was able to center the rudder, go to full throttle and takeoff smoothly.
Once in the air, I tried a roll at about 1/2 throttle. Roll rate was okay, but could probably use a bit more aileron travel. We noticed that both wheel pants had come loose and were hanging down like skis. I figured I wouldn't worry about that until landing time, though. I handed control to the owner, who flew it around for about 5 minutes, at which point the engine quit again. This time, the plane was at medium altitude, and traveling downwind at a location adjecent to the runway's midpoint. I put it into a 45 degree dive and began to execute a 180 degree turn. I started pulling up halfway through, and I ended the turn right over the midpoint of the runway about 5 feet off the ground. The wheel pants were now upside down, so on touch down, the plane proceeded to skid on the tops of them. I hadn't quite completed my turn, so the biplane skidded off the right side of the runway and into a puddle, whereupon it did a sumersault and landed upside down. No damage, but it was kinda muddy and wet.
We still aren't sure why the engine cut out again. It may be that the Magnum engine isn't broken in yet. I've also heard that some people have had problems with the Great Lake's cowl causing over heating. The builder had cut some slots along the back of the cowl where the engine is, though, so it doesn't seem like that should happen, especially since it was a fairly cool day. Maybe Magnums just suck.
So, to sum up, I'd say that this is a really nice flying plane. Admittedly, I didn't get that much time to wring it out, but it doesn't seem to have any bad habits, apart from a pretty high sink rate during a dead stick. I can't comment on vertical performance, as I really didn't do much flying in that regime. I didn't really do any aerobatics either, accept for the roll, but the short wings, four ailerons, and fairly neutral behavior make me think that this should be a pretty snappy performer.
I don't think I'd reccomend this as a first taildragger, due the the ground handling. While it doesn't seem to be excessively tail happy, or prone to ground looping, it can require the pilot to be active on the rudder during the takeoff roll. It certainly isn't as rock solid stable as my Model Tech Dragon Lady, which barely needs any right rudder. I must also point out that conditions were nearly ideal. With a cross wind from the left, its possible that this plane might be a handfull. Still, it is 1000% better then what I had expected after reading some stuff about it in rec.models.rc.air newsgroup.
All in all, I give it a thumbs up!
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