Of Wings & Things returns

This is the inaugural relaunch of a grand tradition, the wonderful and eclectic “Of Wings & Things” column created in 1972 by aviation historian and renaissance man Peter M. Bowers.

For more than three decades, Pete blended a series of photographs with his encyclopedic knowledge of aviation to create an interesting story in each column. Sometimes vintage, sometimes current, sometimes military, and always intriguing, Pete’s column was a package I looked forward to receiving when I was editor of General Aviation News‘ predecessor, Western Flyer, in the late 1970s.

Spending my teenage years in the Seattle area, I gravitated to a fascinating aviation scene of homebuilders, antiquers, and museum makers. Pete Bowers had a hand in all of that. He was a mentor before I knew the significance of the term.

Soon I began taking aviation photos with an eye toward storytelling documentation like Pete did. My rudimentary file system copied his. I even bought a vintage camera in 616 film format to experience making large negatives similar to the ones Pete and other aviation photographers had been swapping since the late 1930s.

I wanted to be a storyteller like Pete Bowers. Pete was encouraging and generous, both with his photos and the occasional well-deserved criticism.

Pete Bowers pioneered and popularized aspects of historical aviation writing that others continue to emulate. His contributions live on. He was the master of this explanatory aviation history genre. And now, each new “Of Wings & Things” column in General Aviation News will be an unabashed homage and a heartfelt tip of the hat to Peter M. Bowers. Let’s get started!

Something Borrowed

Part of the romance of aircraft development is the notion of a clean-sheet design — an aircraft created from scratch to meet a need.

But aircraft designers have long shunned the folly of reinventing the wheel — or the wing, or tail — and some design shortcuts have realized economies of time and money.

After World War I, the National Advisory Committee for Aeronautics (NACA) researched and catalogued many airfoils that provided a range of performance attributes depending on the demand. While manufacturers still explored new airfoil designs, these NACA patterns became standards in many aircraft.

But more than airfoils could be adapted. Entire wings and tails designed for a specific aircraft sometimes flew on an otherwise new design.

In 1936, an ambitious Boeing engineer with a flair for sales, Wellwood Beall, began roughing-in the design of a huge four-engine flying boat he hoped the company would consider for submission to meet a Pan American Airways request for proposals.

Beall knew the hull of the proposed Clipper required specific aerodynamically and hydrodynamically influenced contours that could only be created by crafting new metal. But the wings of his vision already existed in the design of Boeing’s one-off XB-15 long range bomber.

All the hours of engineering spent on the XB-15 wing were free for the taking, and Beall assimilated this for his Clipper proposal. When he computed the optimal wingspan of the Clipper should be 152 feet, compared to the narrower XB-15’s span of only 149 feet, Beall’s solution was simple: “Increase span by adding 36 inches to body width,” he wrote in a signed penciled memo.

Every Boeing 314 Clipper that plied overseas routes did so on the wings of an experimental bomber that never moved beyond one prototype.

Nor was the Clipper Boeing’s only use of borrowed engineering. The Boeing 307 Stratoliner was a clear beneficiary of B-17 wings and tail surfaces. Over the evolution and use of the 307s, some unique features were added to the flying surfaces, but the head start provided by B-17 engineering was a key contributor.

And the morphing of the B-29 Superfortress into the B-50 and C-97/Model 377 series is well documented, with wing and empennage similarities abounding.

Less well known is the installation of a Boeing B-29 vertical and horizontal tail assembly on a rival Convair B-32 bomber. The B-32 might have augmented the B-29 as a very long range bomber during the war, but its developmental issues had the effect of hobbling the B-32 project more than did the problems faced by Boeing’s B-29 team.

In December 1943, the Army Air Forces recommended that the early twin and canted tail surfaces of the XB-32s be replaced with a conventional single fin and rudder. The solution: Attach a tail unit from a competing Boeing B-29 Superfortress. The geometry of the B-29 fin and rudder are evident in early photos of the modification, but Convair soon made changes to increase the size of the vertical tail, and the Boeing “look” was lost.

Still, intriguing vestiges remained on the 112 production single-tail B-32s that followed. The horizontal tails of both B-29 and B-32 span exactly 43 feet, with an identical chord at the root of 11 feet, 2.4 inches. A quick look at a B-32 Erection and Maintenance manual lists part numbers for the horizontal tail surfaces including items with a BAC — Boeing Aircraft Company — part number. Wartime necessity evidently trumped clean-sheet design.

Evidence of borrowed component design is everywhere. Boeing’s famed B-17 Flying Fortress also has a horizontal tail of similar planform — and a span of precisely 43 feet.

Even if modifications ensue, the basic economies of using an existing plan has been an attractive option for aircraft designers for decades.