Grumman Goose Seaplane Replica
Case Study: Building a Scale Replica of a G-21A Grumman Goose Seaplane
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Grumman Goose Seaplane Replica
The Grumman Goose G-21A seaplane flew in the Caribbean for nearly three decades, transporting locals and tourists from island to island. The Goose was one of the many (and probably the most memorable) planes in the Antilles Air Boats airline fleet. When WhiteClouds was asked to make a 1/2 scale replica of the historically significant seaplane, we were up for the challenge.
The creation of a scaled-down seaplane replica, intended for permanent outdoor display, is no small task. The build would have to endure being outdoors in a tropical climate for many years. The WhiteClouds team took action to design and build a model that would withstand hurricane-force winds and extreme weather conditions.
The decision to make the plane replica as a composite structure was made early on in the planning and conceptual phase. The incorporation of a sturdy steel frame and fiberglassed, UV resistant exterior, was the ticket to ride. This heavy-duty and one-of-a-kind outdoor display was built to last.
WhiteClouds worked closely with the client to recreate their vision and the design phase took about a month to finalize. Design iterations would change the left banking of the plane from 5° to 10° and the fuselage height from 5 feet to 4 feet off the ground.
The client’s budget restrictions omitted the finer details such as rivets, wires, and bolts found on the original Grumman Goose.
The approved design plan included a heavy-duty cold-rolled steel internal structure, plywood, 3D prints, fiberglass, and two-pound expanded polystyrene (EPS) foam.
The internal structure is a frame built from 18 gauge cold rolled steel. This frame was welded in-house and then weather-treated to prevent rusting if moisture were ever to come in contact with the frame.
The steel frame acted as an armature to attach the composites to. Half inch plywood sheets attached to the steel armature created a surface for the EPS foam to adhere to.
Cut on the hot wire CNC machine, many slices of EPS foam were placed and glued to the inner structure to form the fuselage and wings. Hand-sculpting gave the form further refinement to match the design.
A layer of aluminum foil was applied to the raw EPS foam to create a barrier for the fiberglass and resin coating.
The fiberglass treatment gave a protective layer of strength and durability needed for this replica to weather a hurricane. Once the fiberglass resin dried the body work commenced.
Imperfections were filled and the surface was extensively sanded. Once the surface was adequately smoothed, a thick layer of primer prepared the model for paint and finishing touches.
The propellers and the propeller cones were 3D printed. It took 200 hours and 55 printers to complete these plane features.
After printing, the parts were fused together and then filled, hand-sanded, primed for paint, and then sanded again.
The exterior of the plane has an automotive-grade paint finish with vinyl decals. The windows were painted blue to imitate glass.
An Antilles Air Boats logo along with the United States Virgin Islands flag were printed in vinyl and then applied to the plane before the scratch resistant UV coating.
The plane will mount on top of a concrete slab with support from four welded steel posts that extend from the lower portion of the frame.
Grumman Goose Seaplane features a unique vinyl decal detail. The replica is designed to break down into two parts to avoid overlength shipping charges. The wings detach from the fuselage and easily reassemble on-site through a hidden compartment at the top of the plane.
The plane will travel by motor cargo to a port in Florida and then load onto a boat to complete its journey to St. Thomas.
To learn more about our large product replicas, please visit our page here.
Finished Model Facts
- The finished replica weighs 2,300 pounds.
- The plane measures 15 feet from tip to tail with a wingspan of 19.5 feet.
- The plane is designed to look like it is taking off for flight with a 5° pitch and a 10° bank.
- The nose cones for the propellers took 68 hours and the propellers took 132 hours of print time on our Creality FDM 3D print farm.
- The plane will mount to a concrete slab at the Cannon Lawn of the Yacht Haven Grande in St. Thomas U.S. Virgin Islands.