First look: SeaMax light sport amphibian

August 12, 2008

One of the biggest attractions at AirVenture each year isn’t even at Wittman Regional Airport. It’s the seaplane base on nearby Lake Winnebago.

It’s a place caught somewhere between sea and sky where boating and flying merge underneath the busy Oshkosh arrivals several hundred feet above. It has that laid back, bohemian atmosphere where you expect Jimmy Buffett to pop out somewhere.

The cove where the seaplanes moor has its blind spots, so unofficial controllers keep in radio contact with pilots. Old timers tell wild stories about actually landing in the cove way back when.

I’m fortunate enough to bum a ride in the SeaMax light sport seaplane to see if it is as fun as it looks. It has a bulbous canopy and V-shaped composite fuselage. Beyond that is where the airplane begins with a wing and a boom-shaped tail. It’s manufactured in Brazil by Airmax and reassembled in the United States. So far one is in customer hands and several more are being readied for delivery. There are 89 flying worldwide.

No hand pumping

Open the canopy and it reveals a wide cockpit, nearly four feet. While this might be an impressive dimension, the SeaMax is a light sport airplane, after all, and incoming lake waves puts its small size in proportion. The side rails are low enough to make getting in easy even when you’re standing in the water. Once seated you can reach over the rail and cup the water. In other words, you can paddle it kind of like a canoe.

I’m flying with Malcolm Jones, one of the SeaMax USA company representatives. The nose is already pointed out to sea, so with another person holding the wing we hop in and fire up the 100-horsepower Rotax 912 ULS.

The electromechanical stainless steel landing gear can be lowered in nine seconds while the seaplane is in the water for taxiing up boat ramps. Normally, LSAs are not allowed to have retractable gear, but there’s an exception in the rules for amphibians. The company says the SeaMax can be used for salt-water operations thanks to its stainless steel exhaust system and other seagoing features. The SeaMax also has a ground-adjustable three-blade prop.

The airplane had been sitting in the water all week doing demo flights, and Jones says it hasn’t leaked. But water from dripping feet adds up. To clear it, just activate the electric bilge pump. This saves you the trouble of the endless hand pumping required by traditional airplanes on floats.

Making waves

Jones doesn’t feel he has enough time in the right seat to be comfortable with me in the left, and I’m not exactly seaplane current, so all of the impressions from here on are preliminary. We’ll wring out the airplane more thoroughly at a later date and examine it in all its configurations.

With the low waterline, you have to be careful about waves when the canopy is open on its forward hinge. Sponsons mounted underneath the wings let the heavier wing dip. It doesn’t take much for water to wash up and over into your lap. This is also part of the fun. To stay dry, just close the canopy.

Once the oil pressure comes up, Jones throws the throttle forward. There are two levers on each side of the cockpit, more like a powerboat or fighter plane. There is a center-mounted stick with the electric trim controls built in. The flaps are also electrically actuated.

The SeaMax takes off in surprisingly little space. I estimate 500 or 600 feet, which is consistent with the manufacturer’s specs. Being inside the hull instead of riding high above the water on floats gives you a sense of what the lake is doing. And with the airplane’s small stature, you feel the slightest chop.

SeaMax seaplane

Base price: $137,000
Price as tested: $142,000

Specifications

Powerplant: Rotax 912 ULS 100 hp
Length: 19.8 ft
Height: 6 ft
Cabin width: 3.9 ft
Wingspan: 28.7 feet
Seats: 2 (side by side)
Empty weight: 770 lb
Gross weight: 1,320 lb
Useful load: 550 lb
Payload w/full fuel: 400 lb
Fuel capacity: 25 gallons
Baggage capacity: 44 lb

Performance

Takeoff distance (land): 500 ft
Takeoff distance (water): 450 ft
Landing distance (land): 500 ft
Landing distance (water): 500 ft
Rate of climb, sea level, gross weight: 1,000 fpm
Cruise speed: 100 kt @ sea level
Maximum speed (V NE): 160 kt
Stall speed (clean): 42 kt
Stall speed (flaps): 31 kt
Range: 450-plus nm

Airborne

Once airborne, Jones demonstrates some landings. Thanks to the flaps it comes in amazingly slow. The manufacturer says it can cruise at 90 to 100 knots but stalls at 36 kt in the dirty configuration. Because of the Oshkosh traffic, we can’t take it high enough to check the numbers. When you make contact with the water, it sounds like rain hitting a tin roof. The seaplane draws only two inches so you can almost land in a puddle or pretend like you’re a swamp boat and step taxi over weeds.

Part of seaplane flying is reading the water to keep tabs on the wind. It determines your direction of takeoff and how you plan to dock or beach using a technique called sailing. I can see how a seaplane like the SeaMax requires some thinking, particularly if you plan to get into an area with trees, then execute a dismount from the cockpit. The wings are made with an aluminum spar and metal ribs and covered in fabric. With the potential for dinging docks and trees, the company was afraid an all-composite wing might hide damage. The wing tips and control surfaces are fiberglass for easy replacement.

We take off again, eating the chop, and cruise around at 80 kt or so just off the deck. Everybody loves to see seaplanes no matter where you go, it seems. Boaters wave with awe and respect. The view from the huge canopy is unrestricted and spectacular.

Back to reality

Jones turns the stick over to me and the seaplane handles with ease. The controls are light and responsive. A Garmin 496 mounted in the instrument panel provides navigation; weather and traffic data comes compliments of XM Satellite. Jones had flown the seaplane from Florida and said it was easy dodging bad weather and airspace. Cruising at 90 kt he and a passenger and a baggage compartment filled with camping gear burned 4.5 gph. A Dynon glass panel as well as a few steam gauges complete the rest of the panel.

We overfly the cove, and its time to head to the seaplane base. As we water taxi up, there’s a crowd of about 50 people watching all the seaplane action and taking pictures.

“Was it fun?” a man asks me.

“Oh yeah,” I say. “It’s going to be hard to go back to landplanes.”

Of course I have no choice.