Peter Garrison
The Staggerwing was the climax, and the end, of an era.
Late in 1932, the newly formed Beech Aircraft Company flew its first product, a five-seat biplane with a 420-hp radial engine and fixed landing gear enclosed in huge fairings. Walter Beech gave it model number 17, since the last model built by the Travel Air company, which he had founded in 1925 with an all-star cast of Clyde Cessna and Lloyd Stearman and sold in 1929 to Curtiss-Wright, had been its 16th.
The United States was in the midst of the Great Depression, and buyers for the big biplane were hard to find. In a reckless moment Walter Beech decided to advertise that it was also available with a 690-hp Wright Cyclone engine. In fact, none had been built and flown with that engine, and the factory was actually heading in the opposite direction, developing a tamer retractable-gear version powered by a 225-hp Jacobs. But as luck would have it the offer came to the attention of Robert Fogg, the company pilot of the Goodall Worsted Company of Sanford, Maine, creators – somewhat ironically, given the geography – of the popular “Palm Beach Suit”. Goodall ordered one.
Beech reinforced the empennage and stuffed the big heavy Cyclone as close to the firewall as it could go, giving the aeroplane the squashed face of a pug dog. The short-coupled, narrow-geared A-17F was claimed, somewhat implausibly, to be capable of 217 knots, but it turned out to be quite a handful to fly, and in due course Goodall sold it. It flew in a couple of transcontinental Bendix Trophy races, but with disappointing results.
In 1936 the landing gear collapsed under a heavy fuel load before the plane got into the air. On the next try, the engine quit a little short of the finish.
The definitive early production Staggerwing was the 1934 B model. It had retractable landing gear and the Jacobs engine, and achieved the sedate cruising speed of 140 knots, which was really not bad for such a big aeroplane with such a small engine. Later models got twice the power, in the form of a 450-hp Pratt & Whitney R-985. In principle doubling power should add 26 percent to speed, and indeed this version cruised near 180 knots, a gratifying instance of aviation reality conforming to theory.
During World War II, hundreds of Stags served as both the quaintest and the most charismatic personnel transports in the military fleet.
In 1948, having replaced the charismatic Staggerwing with the entirely different, but equally iconic, V-tail Bonanza, Beech ceased production of its glorious but anachronistic biplane.
The Staggerwing got its nickname from the arrangement of its wings, with the lower wing 25 inches ahead of the upper. The term “stagger” refers to any difference in the longitudinal locations of a biplane’s wings.
The prevalent arrangement has always been “positive” stagger, with the upper wing farther forward, probably because during the First World War pilots found it more useful to be able to see downward than upward. (Nevertheless, the negative-stagger De Havilland DH.5 of 1916 was praised for its “first class view forward and upwards.”)
There is no compelling aerodynamic reason to prefer one over the other, as is apparent from the fact that the few negative-stagger biplanes that exist are not notably defective performers. The principal requirement of a biplane, from a stability standpoint, is that the more forward of its wings stall first, so that the aeroplane naturally pitches down when stalled; this can be accomplished, regardless of the type of stagger, by adjusting either the aerofoils of the two wings or their angles of attack, or both.
The reasons for the negative stagger of the Model 17 were, I suspect, two. The one more often cited in published accounts of the aeroplane is to provide better visibility for the pilot, who would naturally be seated ahead of the CG. (In many multi-seat biplanes of the Twenties, including several Travel Air models, the pilot occupied a rear cockpit, separate from the passenger cabin, for reasons of balance.)
But the fact that work began on a retractable-gear version so soon after the fixed-gear one went on the market hints at a different and more plausible reason. The position of the lower wing gave the main wheels, which had to be placed well forward in a tailwheel-gear aeroplane, a place to hide. I think it pretty certain that Beech’s chief designer, Princeton-educated Ted Wells, had this requirement in mind from the start.
Wells had previously designed several biplanes for Travel Air, but nothing quite like this. The basic idea was to combine a reasonable landing speed – easily accomplished with a huge wing area of 300 square feet – and a high cruising speed, which would require a powerful engine and exceptionally low drag.
The shape Wells produced is one of beautiful fluidity: you can visualize the air parting at the nose and coming together toward the tail in an effortlessly natural way. Perhaps, just as their professional involvement with bicycles influenced the Wright brothers’ approach to stability and control, Wells’ skill at streamlining owed something to his familiarity with flowing water. Wells was an avid and skilled competitive sailor; in fact he later resigned from Beech aircraft after a tiff with Walter’s wife, Olive Ann, over Wells’ frequent absences at sailing meets. It is not difficult to persuade oneself that there is some kinship between the graceful lines of the Staggerwing and those of a racing yacht.
The low drag of the Stag was due in part to wind tunnel research performed at NACA’s Langley Memorial Laboratory under Fred Weick, who would later design the Ercoupe, and at the Guggenheim Aeronautical Laboratory at Caltech (GALCIT).
The NACA contribution was the round cowling, fully enclosing the engine, that would eventually be used on practically every radial-engine aeroplane except cropdusters, which don’t care about drag. Behind the circular outlet slot at the rear edge of the cowling, the Stag’s firewall blended with a smooth curve into a windscreen so steeply raked as to be nearly flat, and from there seamlessly into the leading edge of the wing.
Although the feasibility of cantilever biplanes had been demonstrated by Fokker during World War I, Wells chose to accept the drag penalty of interplane bracing. But he made use of the thickness of the plywood-skinned Clark and, later, NACA 23000-series aerofoil to carry torsional loads, and replaced the customary N struts and multiple sets of bracing wires with a single streamlined interplane strut and a single pair of wires.
From GALCIT came the wing root fairing, which had been developed for the Northrop Alpha, a very clean all-metal low-wing cantilever monoplane of 1930 similar to the Stag in weight, power and wing loading. The Alpha’s problem, which it shared with most low-wing aeroplanes, was flow separation, particularly in climb, in the diverging channel between the downward-sloping upper surface of the wing and the upward-sloping underside of the fuselage.
GALCIT studies produced the concave wing root fillet, extending behind the wing and blending gradually into the fuselage, that would thereafter grace many low-wing aeroplanes. The Stag’s big fillet swept upward in a gentle S-curve, extending more than halfway to the empennage and giving the aft fuselage the graceful cusped shape of a modern composite single.
Though it was stylish and fast and came at the climax of the biplane era, the Staggerwing was obsolete when it was new. Its contemporaries, like the Alpha and the Douglas DC-1, were metal cantilever monoplanes of the type that would dominate aviation for the next 70 years, leaving the Staggerwing – a nostalgic and inimitable jewel – behind.