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Grumman Model G-21 amphibian.

In 1936, a group of wealthy residents of Long Island approached Grumman and commissioned an aircraft that they could use to fly to New York City. Envisioned as corporate or private "flying yachts" for Manhattan millionaires, initial production models normally carried only two to three passengers (plus two pilots) and had a bar and small toilet installed. More spartan airline versions will carry 6 passengers; the information which follows is for an "exploratory" aircraft, with simple removeable seats for passengers and no "plush" fittings.

The first G-21 flew on May 29, 1937; the name "Goose" is applied by the RAF during the war. During the Second World War the RAF and US Coast Guard will use various models for patrol and rescue work. Over 200 were sold by August of 1938; the RCAF was the first military customer.

It is a high-wing, all-metal cabin amphibian, with a crew of two pilots and capacity for up to 6 passengers. The tricycle landing gear can be manually retracted; the floats are fixed. A basic radio system is fitted. Wingspan 49', length 38' 4". Weight empty 5425 lbs, useful load (pilots, passengers, passenger seats, optional auxiliary fuel tank, and cargo) 2550 lbs.; passenger seats weigh 30 lbs. each.

The pilots sit side-by-side, with full controls available to each. A sort of bulkhead separates the pilots from the passengers, but no door is fitted in the wide opening. The passenger seats are fitted with a narrow aisle between pairs; one to six seats can be quickly fitted or removed. Doors are fitted on both sides of the fuselage, at the rear of the cabin (the port side door is larger). The main cabin is 67" high, and 54" wide, 130" long to the control panel.

There is a small forward compartment, accessible from between the pilots or from a small hatch on the nose, meant for baggage -- 55" high, 49" long, 57" wide; and an aft baggage compartment, 56" high, 50" wide, and 47" long, accessible only from the cabin. There are several "dome" lights in the cabin ceiling, and one in each of the baggage compartments.

Equipment aboard

The engines are two supercharged Pratt & Whitney Wasp Junior SB2 nine-cylinder radials, of 450 HP each; they each weigh 611 lbs dry. Four fuel tanks hold a total of 370 gallons of fuel; an optional auxiliary tank (taking the place of two seat positions in the cabin) can be fitted to hold 116 more gallons, weighs 750 lbs installed and filled. A 7.5 gallon oil tank is fitted in each engine nacelle.

Vacuum-operated flaps run from fuselage to the ailerons on both sides.

Performance:  top speed 200 mph, best cruise speed 180 mph at 5,000' altitude, landing speed 62 mph; range 900 miles on regular tanks (1200 miles with auxiliary tank), ceiling 24,000', rate of climb at sea level 1,000' per minute.

Cost new, $68,000.

The cockpit of a Goose at the NASM:  http://www.nasm.si.edu/imageDetail.cfm?imageID=1649

Print this plan about 7.153" long; it'll be just a bit more than 1" wide in figure scale: