Friday, March 1, 2013

Burnelli's Better Idea (That Went Nowhere)

Vincent Burnelli may not be quite as well known as Jack Northrop, but that doesn’t mean that he wasn’t just as passionate and dedicated to his vision of how aircraft design could be improved. While Northrop pursued the idea of a pure flying wing, Burnelli sought the aerodynamic benefits from the lifting body concept, where the fuselage of an aircraft is shaped to provide a significant portion of the plane’s lift.

Burnelli was one of those brilliant designers whose ideas were always just ahead of the curve enough so that they never met with commercial success. During WWI, his design for a night fighter was rejected by the Army, but was bought by the NYPD who wanted to set up the nation’s first police aerial unit. In the early 1920s, he built two different biplanes that had airfoil-shaped fuselages, and in 1928 he came out with his first monoplane, the CB-16, which was the first twin-engine aircraft in history to be able to maintain altitude with one engine inoperative.

Burnelli believed – and was backed up by NACA studies – that the fuselage, instead of being an aerodynamically useless drag-generator, could develop a significant portion of the aircraft’s total lift. His goal was 50%, and wind tunnel studies showed that, depending on the angle of attack, the fuselage could actually generate up to 90% of the total lift. Besides the aerodynamic efficiencies that he believed his designs incorporated, he steadfastly maintained that the lifting body design also had certain inherent safety features. Up to 60% of the aircraft’s total structure surrounded the passenger cabin to prevent it from collapsing in a crash. This was proved, to a degree, when the CB-16 prototype stalled and crashed on takeoff in 1929…the two pilots survived with no injuries what would have normally been a fatal impact. The CB-16 design led to the UB-20 (which made a media splash when a Ford convertible automobile was strapped to its belly and flown over New York’s Floyd Bennett Field in Sun Oil stunt to prove that the car would still run when subjected to freezing temperatures at altitude) and then to the improved UB-14 airliner.

The prototype first flew in late 1934, but crashed on January 13, 1935. Flown by Louis Reichers, a maintenance-related control system problem led to a loss of control. The plane rolled into a steep right bank very near the ground, and impact at almost 90 degrees to level. The wings and twin tails disintegrated and the fuselage “box” cartwheeled, but once again, the structural safety features proved their worth, and the crew survived.

In Reichers’ subsequent report, he wrote "The indicated air speed was 195 m.p.h. at the time it became essential for me to make a crash landing. I flew the ship into the ground from about 200 ft. altitude and estimate the speed of contact at about 130 m.p.h. the right wing being nearly vertical and absorbing the first shock. This impact caused the airplane to cart wheel tearing off the engines and crashing the wings and tail group with the body tumbling, though remained intact and no fuel leaked from the wing tanks. It is my firm belief that the fact that the box-body strength of this type combined with the engines forward and the landing gear retracted saved myself and the engineer crew and had the cabin been fully occupied with passengers with safety belts properly attached, no passengers would have been injured. This crash landing, in my opinion, is an extraordinary example of the crash safety that can be provided by the lifting body type of design." (A small video of the crash can be seen here.)

A second aircraft, UB-14B NR15320 was then built – this is the aircraft shown in today’s photo. At 41 feet long and with a span of 71 feet, this was no small aircraft. The plane’s two-person crew sat high above the main cabin in a cockpit built into the leading edge of the wing/fuselage, between the two 750-horse Pratt Hornet engines. The luxuriously-appointed passenger cabin measured 12 feet long, 11 feet wide and sat 14 passengers. A lavatory with running water was also provided. The UB-14 was the first multi-engine plane to incorporate wing flaps. Despite all the advantages of this design concept, it failed to garner political or commercial support to any great extent in the US. In fact, it was later alleged that Burnelli’s designs were barred from consideration by the US military – despite strong support from General “Hap” Arnold – on orders from Franklin Roosevelt, who was not happy that one of Burnelli’s main financial backers was Sun Oil’s Arthur E. Pew, who had funded the campaign of Roosevelt’s rival Wendell Wilkie. The political issues soon raised all sorts of conspiracy theories about darker forces at work preventing Burnelli’s designs from becoming reality.

Overseas, though, interest continued to grow. The Scottish Aircraft & Engineering Company was initially established to license-build UB-14s, and when this company went into receivership, a company called Cunliffe-Owen stepped up to build them at Southampton. In late 1937, NR15320 was shipped to the UK and flew a series of demonstration flights before returning to the US, where it was then prepared for an around-the-world record flight attempt, to be flown by Clyde Pangborn. WWII got in the way, and the world flight was cancelled. During the war, the plane went into service with TACA, hauling freight between Miami and Honduras. After that, its history becomes murky. It supposedly was shipped to Finland and possibly Russia, although there are no concrete records of this. Its ultimate fate is unknown.

Cunliffe-Owen would eventually build only one very modified version, the OA-1, and Pangborn flew that plane’s maiden flight. It would be pressed into service by the RAF, who handed it over to the Free French Air Force. Ultimately, it languished and was cannibalized at El Kabrit, Egypt. On the night of VJ day, the carcass was reportedly used as the basis for a celebratory victory bonfire.

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