by Dennis Parks,
Library/Archives director
(Vintage Airplane magazine)

Daniel Guggenheim International
Safe Airplane Competition

Part 5
Burnelli Entry

Of the 15 aircraft that showed up for the safe airplane competition trials at Mitchell field on Long Island, the most unusual in concept was a Burnelli mono plane entry, X-124H. The 1930 edition of LICENSED AIRCRAFT listed the aircraft as the Uppercu-Burnelli UB SS and registered to the Uppercu Burnelli Aircraft Corp. of Keyport, New Jersey. It was registered in 1929 and carried the serial No. 10.

The aircraft was a Cirrus powered twin-engined mono plane. Among its features were four-wheel landing year, twin tail, wing tips floating ailerons and, its most technically advanced feature, the variable camber wing. The aircraft was described in the December 14, 1929 issue of Aviation.

"A combination of variable area and camber is employed among the many interesting features of the Burnelli airplane built by the Uppercu Burnelli Corp. in the plant of the Aeromarine-Klemm Corp. at Keyport. This airplane embodies a number of the features incorporated in former Burnelli machines."

"The most noteworthy of these features is the idea of a central airfoil body or fuselage intended to contribute lift by virtue of its airfoil shaped profile. As in the case of former Burnelli planes, this machine, which is purely experimental, is powered with two Cirrus engines mounted as closely as propeller clearance permits in the leading edge of the structure, which constitutes the fuselage. These engines are mounted in such a way that their longitudinal center lines are inclined outwardly at a small angle to the line of flight in horizontal plane. This has been done in an effort to provide adequate rudder control when one engine is used alone, and is a feature incorporated in former Burnelli creations."

"The variable area and camber device is a development worked out by Mr. Burnelli in collaboration with Mr. E. Burke Wilford several years ago. The wing section is of medium thickness and of the portion between the spars is rigidly mounted and braced. The design is such that the nose and trailing edge portion move outward and downward, changing the curvature as well as the area. This is accomplished by a rack and pinion mechanism with pinion gears mounted every five feet on to torque shafts running parallel to the spars."

"The shaft running parallel to the forward spar is controlled by a hand wheel in the cockpit while that running parallel to the rear spar is driven by a chain from the forward one. The pinion gears actuate curved rack members, the ends of which are attached to the movable nose and trailing edge. These rack members are mounted on rollers and guidance and their curvature provides the necessary change in camber. With the object of maintaining a minimum of center of pressure travel, the mechanism has been designed to impart greater motion to the nose sections than that of the trailing edge. Strap guides are placed at appropriate intervals to prevent the necessarily flexible portion of the skin from crinkling."

"As previously mentioned, the airplane is constructed of metal throughout, aluminum alloy being used for the greater portion of the wing structure, the magnesium alloy being employed in the construction of the racks and guides. Another noteworthy feature of the Burnelli airplane is the landing gear which is of the four-wheel type and is designed to eliminate the tail skid, this being necessary because of the high position of the tail which is supported on outriggers from the airfoil shaped fuselage."

"The rear wheels, which are 22 by 10 inches, are larger than the front ones and are mounted approximately below the center of gravity with no provision, other than the Musselman and tires, to obtain deflection and landing. The forward wheels or considerably smaller, being 12 by 5 inches, and are intended to prevent nosing over. They are mounted a few feet ahead of the rear wheels and the pairs on each side are housed in streamlined fairings. At the rear of each of these fairings is a small spoon which acts to some degree like a tail skid and prevents the tail from coming in contact with the ground under certain landing conditions."

"When the Burnelli plane was first submitted, and ailerons were mounted at the wing tips and controlled by cables from the cockpit. Later this feature was modified and ailerons of considerably less cord and higher aspect ratio were mounted below the wings near the tips."

"The Burnelli plane has side-by-side seating arrangement and is of the open type. The span of the machine with tip ailerons was 49 feet and the length overall 26 feet, while the wing area was 216 square feet. The fuselage is 8 feet wide and 15 feet long while the overall height of the plane is 9 feet 4 inches.  The weight empty is 1640 pounds and a gross weight is 2590 pounds."

Immediately after his presentation at Mitchell Field, the Burnelli mono plane was returned to Keyport, New Jersey for modifications. A deadline of November 30 was set by the competition committee for its return, but the aircraft did not appear and thus it was eliminated from the Safe Aircraft Competition. It would have been interesting to have known its abilities.

[Article reprinted from Vintage Airplane, July 6, 1992, pages 5 - 7]