• Wing Span: 48 in (122 cm)
• Wing Area: 582 sq in (3755 cm²)
• Length: 24.5 in (65 cm)
• Weight: 3.5 lbs (1.6 kg)
• Engine: .25 - .32 2 - cycle

(4.1 cc - 5.2 cc 2 - cycle)
• 3 Servos required

The Drain Storm is an ARF flying wing that uses a 2 1/2" plastic drainpipe for a fuselage and a wing from the Airplane Factory's Kombat Kruizer. This wing is made of rubberized corrugated plastic and has a 3/4" plywood spar and except for a small cutout of the plastic for the fuselage and the addition of control horns, it is ready to install. The kit includes everything needed except the engine, prop, and radio gear. Like all the other Airplane Factory kits, there are no hidden extras like fuel tank, wheels, nuts and bolts, covering etc. Nothing extra is required because this kit is complete.

The construction is very straightforward. First, the instruction should be read through completely before construction is started. Otherwise, time will be wasted looking at the plans instead of assembling the Drain Storm. The tools required for assembly are a drill with 1/8", 7/64", and 9/64" bits, straight and phillips screwdrivers, and pliers and/or wrenches. It is not like other ARF’s in that there is no wood, glue, etc. Holes are drilled in engine mount, the engine is mounted, and the assembly is installed into the fuselage. Next, the tank and receiver are installed and the servos are mounted on the rails. Then, the rudder is mounted. A hole must be drilled 3 3/8" from the balance point of the fuselage for the main wing bolt then the wing is mounted with 6-32 screws. The model is balanced by moving the servos on the rail sub-assembly to set the balance at 2" behind the leading edge. Finally, the servo rails are fixed with screws and connected to the receiver. With the addition of some color trim, the Drain Storm is finished. The fuselage to wing joint looked like it would allow spent fuel and oil to get inside the fuselage. After the Drain Storm was assembled, a bead of silicon sealer was added along the joint.

The Hitech Prism 7 does not have elevator/aileron mixing so the included sliding tray was used to control the ailerons/elevators. The simplicity and functionality of this unit are impressive. It is difficult to describe the mixer but a simple drawing makes it clear how it works. The entire aileron servo slides when the elevator is moved. This is a very smooth free moving setup with minimal play.

The Drain Storm has no landing gear and is hand launched and landed on its belly. The plane felt heavy and there was some concern that it would not have enough power but all that is required is a gentle underhand toss and it takes off. It has a very light wing loading, which works out to 14 oz/sq ft. When the plastic fuselage is covered with spent fuel and oil, the Drain Storm will fly right out of the hand holding it. Landings show why balance is critical. The Drain Storm was balanced slightly nose heavy and trimmed to fly straight and level at half power. It tended to climb a lot at full power and drop the nose a lot at idle. It did not flare well on landing. A slight amount of weight was added to the tail. Once this was done, there was very little pitch change with speed change and landings were great. All that is required is to bring it in and on final approach, chop the throttle and trim to kill the engine and it slides in on its belly smooth as silk.

The elevons were set to maximum throw and rates were set to –25% exponential. The first flight was a little disappointing but at the same time was a pleasant surprise. This plane is very a smooth flyer with very uniform but crisp control. It flies more like a pattern plane than the twitchy fun-fly that was expected. Basically it flies like it is on rails with no surprises other than the odd looks of flying a plane with no tail surfaces. Contrasting trim is required on the top of the wing, as it would be very easy to get disoriented with this model.

The Drain Storm rolls like it has dihedral and requires just a little down elevator to make them perfectly axial. A little aileron differential would make the rolls absolutely axial with no elevator input. The roll rate is quick but not extreme even though it has extra throws. With normal throws and a plain bearing .25 engine it would be quite a gentle plane. Inverted flight is just like normal flight, and is so easy it is not worth talking about. When stalling it, all that happens is the nose just barely drops and it starts flying again. Full elevator at high speed makes tight loops in both directions. More gentle input of elevator will produce loops as large as desired. The control movements got faster and larger after a 5 or 6 flights. The controls, which are not really hinged but just bend one layer of the rubberized plastic, were too stiff at first. It is recommended that the elevons be exercise by moving them back and forth a lot before assembly.

With the ASP .32 and a 9x4 Master Airscrew prop, the Drain Storm jumped out of the launching hand and flew very fast. It had unlimited vertical climb. This is definitely enough engine for this plane. A .25 size engine would provide very spirited flight but with the .32, it is awesome. With the throttle wide open, there is no time to look away as it is a very fast airplane and covers a lot of ground in a hurry. It sounded like the engine was over revving as it unloaded in the air so a 9x5 prop was installed. It still has unlimited vertical but has an even faster top end. Low passes over the runway are very fast and impressive. Low speed flight is uneventful. It you can putt around at 1/4 throttle and do loops, rolls, split-S, or whatever an aileron, elevator, and throttle controlled plane can do at a more relaxed pace. The controls are crisp and precise at all flight speeds. It is a fairly clean design so its slow speed is still quick.

After a few flights, another pilot brought out an over powered Sig Wonder for some spur of the moment combat. The Drain Storm was faster and just as maneuverable. One cut was achieved with the Drain Storm and the 2 planes got very close to a mid-air a couple times. This could be a competitive combat plane. The speed with the ASP .32 and 9-5 prop was too much and tended to shred the streamer. A 9x4 or 10x5 will probably slow it down for combat. On the next flight during efforts to ring it out, a loss of radio control occurred and the plane piled in at full throttle from about 80 feet. The spinner and prop pieces were dug from a hole that was finger deep in the ground. The wing tips appeared to have a slight crease from where it cartwheeled through the pits, but it was barely noticeable. The plane home was taken home and the engine was cleaned the engine. Everything was checked and it was found that the aileron had come unplugged from receiver. All that was required to get it ready to fly again was a new prop and spinner. The Drain Storm sustained virtually no damage from the crash while other planes would have been demolished. Even the Airmadillo Kombat 40, which is flown regularly, is not this tough. In combat, the Drain Storm should provide an advantage being very fast and maneuverable and rugged with the ability to survive mid-air collisions and keep flying where most planes would be totaled.

The Drain Storm was chosen as something a little different, small, and rugged. It turned out to be a much smoother better flying plane than ever thought possible. The only drawbacks found were that the control surfaces were too stiff at first, but some exercise soon loosened them up, and the fuselage to wing joint will allow fuel to get into the wing. At $70 when compared to other .25 size models, it seems a little expensive but considering that it is an extremely rugged ARF with all the included hardware, and no covering or glue to buy it is a pretty good deal. Considering how nice it flies, it is a real bargain.