Let's consider light amphibious aircraft - the boathull variety, not floatplanes - but including both freshly designed, fully built light sport aircraft along with kit aircraft born of the ultralight heritage. In the last year, the exceedingly handsome Icon A5 has made quite a splash, literally and figuratively. However, the A5 is more than a year away from first deliveries and an order placed today might not be delivered until 2011 or later. Another LSA amphibian called the Mermaid was designed and introduced by Czech Aircraft Works of SportCruiser fame. Although five are available in the country, sales have yet to take off. Another popular American seaplane, the SeaRey, is moving toward ASTM approval but remains a kit that asks several hundred hours of a builder's time. The simpler and faster-build Aventura models also remain available; this design has been on the market for many years. Either kit is less costly than a fully built aircraft, but all seaplanes have loftier price tags to cover their ability to operate on land or water. Let's put the cost of LSA amphibians in perspective: The cost of adding amphibious floats to a certified 4-seat general aviation aircraft can be greater than the price of an entire Light-Sport Aircraft amphibian. Somewhat behind the scenes compared to the A5 or Mermaid, the little SeaMax M-22 has won its Special Light-Sport Aircraft approval and started making sales. With the sleek looks of modern composite LSA, the SeaMax is sized and shaped closer to ultralight dimensions. The A5 and Mermaid are each pushing against the top of the allowed weight range of 1,430 pounds for seaplane LSA, while the SeaMax weighs significantly less. In light aircraft a significant weight difference can bestow handling and performance advantages. Light on Its Sponsons Compared to the A5, Mermaid or SeaRey for that matter, the SeaMax is remarkably light. When it first arrived in the USA, the SeaMax weighed in at a positively diminutive 1,144 pounds gross, an unheard-of low weight for a deluxe, fully enclosed amphibian that looks this good. As it won approval under the ASTM standards for Light-Sport Aircraft, SeaMax increased capacity to 1,320 pounds. However, since LSA floatplanes are allowed to weigh 1,430 pounds, the SeaMax still comes in 110 pounds lighter at gross and does even better in empty weight comparison. All this makes for more useful load. The amphibious SeaMax tips the scales empty at 750 pounds, giving it a 570- pound useful load. Even with a full load of 25 gallons of fuel, the SeaMax still boasts a payload of 420 pounds, enough for two beefy 200-pound occupants plus 20 pounds of carry-on gear. The SeaMax M-22 appears physically small from the outside.With the wing chesthigh for most people, the SeaMax looks tinier than it is and the light weight surely contributes much to the relative high performance of this flying boat. Light and small it may seem, but when you step inside, you'll find the interior to be surprisingly roomy. Created by Brazil's AirMax Construcoes Aeronaticas, the SeaMax is designer Miguel Rosario's 22nd design and his experience shows. The M-22 is very well thought out with many details not present in other LSA. Rosario, whom I met at Sun 'n Fun '07, said that it was first designed for a wealthy Brazilian businessman and that man wanted it to be a deluxe aircraft. Since its introduction, SeaMax sales have reached 90 units flying worldwide, mostly in Europe where government approval was possible some years ago. An established dealer in Norway sells the most but units presently in the U.S. are available for quick delivery. Five SeaMax LSA are registered in the U.S. The AirMax's work to meet ASTM standards relied on Rosario's long design history, but he received engineering assistance from a Mr. DeCastro, widely revered as one of the greatest aeronautical engineers in Brazil. Rosario also had a serious and talented U.S.-based partner in Carlos Bessa - who conveniently speaks Portuguese, thereby aiding communications with AirMax on a daily basis. Bessa is the quality control manager in the USA for AirMax and sources parts from Aircraft Spruce, Warp Drive, Lockwood Aviation, Gulf Coast Avionics and similar suppliers. The more closely you examine the SeaMax, the more you realize how well thought out and well finished it is. A technically astute friend, Matt Taber, observed how small and efficient the landing gear is, a marvel of few parts that helps restrain weight. Taber also noticed the numerous stainless steel components used, among other applications, to secure the horizontal tail plane after shipping. All work appears beautifully executed. Other clever ideas include an intake at a wing leading edge opening that directs air to the hull's step location to help "unstuck" from the water's surface. When the canopy is open, you can remove the instrument panel top for easy access to the instrument wiring and plumbing. Further, when that canopy is open, you can see an aluminum tube perhaps a foot long well forward in front of the passenger. This allows placement of some lead for additional weight should the pilot not weigh enough. The Sea Max has a minimum pilot weight of 140 pounds; lighter solo pilots would add ballast weight. Once the tinted canopy is closed, you no longer see the tube. Enviable Complexity An amphibian is more complex than a landplane, period. Retractable gear, water rudder, a bilge pump and sponsons result in more to manage along with considerations of hydrodynamics in addition to aerodynamics. Yet many pilots enjoy the task and thrive on the added freedom amphibious flying can bring. Electromechanical landing gear takes about 9 seconds to fully retract. Lights illuminate the gear position and strategically placed convex mirrors can provide visual confirmation. SeaMax provides a digital flap position indicator, digital trim position indicator, electrical fuel boost pump, dual wing landing lights, plus dual throttle levers and brakes. The SeaMax's interior comfort is excellent, with a slick, speedboat-like finish. Cabin width also belies the diminutive-appearing exterior; at 47 inches, the SeaMax is half a foot wider than a Cessna 172. The canopy optics are excellent and you have 45° aft visibility through quarter windows. Leveraged door latches move in a small range and are therefore firmer to operate and latch with a very secure feel and sound. The door lever hardware is a simple and light system with an added little touch - the interior portion of the door handle has a pointyend, which is thoughtfully bent inwards so you don't snag your clothes on it. In addition to air vents in the canopy -- the common half-cup-shaped, flip-out ones - the SeaMax has a second set near your head, tucked away in the wing root area. The interior ones resemble those on airliners. I found the seat belts challenging to adjust; the adjustment buckles are too close to the seat sides. This wouldn't matter if you sit in the same seat all the time, but it's awkward when a different-sized person tries to tighten or loosen the belts. Since my flight, the company has found a domestic source for seat belt systems and reports buckle access problems are history. When taxiing on land with the canopy open, the hinge components proved robust; even on a bumpy turf runway, the canopy moved very little. This provides plenty of airflow for warm days. However, the reach to pull the canopy down requires you to loosen or slip off your shoulder belts. Alternatively, Bessa said you could add a strap to the canopy for easier use. The 100-hp Rotax 912S easily powered the SeaMax on land or water.With Bessa flying, we zipped around on the water at 45 mph. The SeaMax makes a great little speedboat using only 2,800 rpm to sustain a brisk pace. Turning in this configuration, a pilot would employ the water rudder -- which extends from inside the air rudder (the same as it does on the Mermaid) - and demands opposite aileron to keep from sticking a sponson too deeply in the water. Rising Off the Water On full application of power some water spray may contact the prop so the AirMax utilizes a Warp Drive metal-reinforced leading edge on the propeller. Because the SeaMax is a small airplane, when sitting still in the water, the cockpit side rails are only inches above the water line, and the bottoms of the occupant seats are below the water line. Therefore, while it may be possible to fly in some waves with experience and good technique, I consider this a smooth-water airplane. I heard reports of operations in 1-foot waves, but I believe it would be uncomfortable when you slowed to idle speeds in such swells unless you have considerable experience with the SeaMax. Using Bessa's takeoff technique I applied full power and held the stick full aft until breaking ground. As the nosewheel lifts, you relax the backpressure and let the plane fly itself off the surface. Rotation occurs at about 45 mph indicated on the Dynon digital PFD. Climbout at 70 mph produced about 1,000 fpm initially. The SeaMax sustained climb at about 700 fpm with 10° of flaps. Repeating the land takeoff on water was similar except you let it fly off the water with such vigorous control. The SeaMax's hull gets on the step in about 100 feet, says AirMax. With continued acceleration, takeoff follows in another 200 feet when flying solo, or another 400 feet when flying dual. During landings with full flaps the aircraft approaches at 50 mph. A good downwind speed is 75 to 80 mph; this produces about 500 fpm down with the throttle at idle thrust or about 2,500 rpm. Water touchdowns proved very straightforward. The SeaMax responds very well as a boat. Touchdown was at about 60 mph and it immediately started tracking straight and true. As I slowed down, Bessa advised me to pay attention to the transition from airplane to boat. He says it is essential to keep the stick full aft to prevent porpoising and possible upset. Other pilots who have flown the SeaMax believe takeoff and landing operations are easier on water. Maybe that's because of the openness of landing on lakes compared to the constraints of hard-surface landings with fixed boundaries. Landing on land means you have to make sure the wheels are down, of course. The action is easy in the SeaMax, thanks to electromechanical gear using an overhead-retracting knob. Three green lights at the top of the panel confirm what you can also visually check in small convex mirrors on the sponsons, though you may have to raise a wing to have the reflection of wheels against the sky and not obscured by ground clutter. For water landings, it appears best to use an attitude landing technique where you establish a speed via angle of attack and wait for contact. Certainly this is the advised method when landing on glassy water where reflection makes it very difficult to see precisely when to flare. The steady descent to touchdown feels quite firm on the boathull, but Bessa indicates the structure easily stands up to the job. Responsive Handling Let's face it. Seaplanes often become more sluggish than their land-based siblings because of a considerable extra weight hanging well below vertical center of mass. Light-Sport Aircraft amphibians will be better than heavier general aviation seaplanes, but the SeaMax is above average in its class. In a general way, the SeaMax reminded me a lot of the Flight Design CT series (or several other high-end LSA) in that each machine is a "performance LSA." My analogy of a Cessna 172 being a "sedan" and the CT being a sports car brings nods of agreement from others with experience in both. Flying a SeaMax evokes a similar response. Like any vehicle in the "performance class," it may take a bit longer to handle it masterfully. After my first two flights in the SeaMax, I was not comfortable enough to take a passenger in the airplane. Bessa's partner, Malcolm Jones, an experienced pilot himself, said he felt similarly at first. Yet after my third flight and accumulating nearly 4 hours I began to feel much more comfortable in the SeaMax. Given insurance industry requirements to get at least 5 hours time in type, most experienced pilots would become comfortable with the SeaMax in that time. The SeaMax joystick is nice and light. I wandered a bit as ailerons and elevator were easier than the rudder. My initial efforts at mild Dutch rolls were sloppy, suggesting handling that takes acclimatization. Rudder control posed some challenge. It has some momentum that I suspect may have been induced by the large cabin, a pusher engine, and closely coupled tail. You need to use the rudder, but bumping motions of the pedals seemed best. To smoothen airflow around the large cabin, designer Rosario put in a long investigation into the vortex generator tabs seen in many locations. Such an advanced investigation into airflows is another example of the thorough approach by the designer. Bessa likes to use 4,800 rpm on the 100-hp Rotax 912S for normal cruise and that produces about 100 mph. I noted that at 4,600 rpm we showed slightly less than 100 mph. The SeaMax has a negative or reflex position on the flaps, which adds a few knots to cruise speed.When we reflexed the flaps, speed crept up another 3 to 5 mph. At such a lower power setting fuel burn would be quite reasonable, in the range of 3.5 gallons per hour. Stalls were modest and came at surprisingly slow speeds. In my experience, using installed instruments that sometimes have lower-speed-range error, stall happened at about 43 mph. Even with a few miles an hour of error, this qualifies as a very slow stall. Stall recovery qualities were mild with full control and fast results. SeaMax in Your Future? Fully built seaplanes are not your lowest cost options to fly, but they offer enviable versatility and the LSA seaplane versions cost far less than their general aviation counterparts. The whole amphibian LSA costs less than amphibious floats alone for a general aviation airplane. Among LSA boathull amphibians, the SeaMax is comparably priced to other offerings with a current quote of $137,000 base price for a nicely equipped aircraft. And this amphibian is available on short notice. Some of the SeaMax price is due to relatively small production, and complexities like retractable gear that adds cost no matter how efficient the producer. Fortunately for the SeaMax, the perceived value may also be higher due to its versatility, its highly engineered design, and the deluxe speedboat-like finish. The high quality of building execution helps justify the asking price, but it's hard to put a price on the pleasure a true amphibian like the SeaMax can provide.