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In service, the Nieuport 28 had a good performance, due to the aircraft’s good maneuverability, impressive rate of climb and speed. But the fighter also had several issues. The most well known was the tendency to shed its upper wing fabric if the pilot pulled out of a steep dive too quickly. The problem was not the dive, but the pull out that wrecked the wing. Pilots, such as the ace Harold E. Hartney, noticed that despite the deformed appearance of the failed upper wings, in most cases control of the aircraft was maintained and the machines could land safely.


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The upper wing of the Nieuport 28 failed because the wing rib failed in its function of transferring the heavy loads encountered at the leading edge of the wing to the main spar. The portion of the rib forward of the main spar was poorly designed and so structurally weak as to concentrate the shear and bending moment force on the veneer above the wing and the very thin cap strip below. These structures were inadequate to the task. The fix (nailing and gluing a wood strip or batten atop the veneer) adopted after the spate of accidents added nominal strength to the top of the leading edge of the upper wing, but it did not address what was principally lacking in the rib construction. A shear tie is required to securely connect the web to the spar and add the necessary rigidity forward of the main spar to manage the heavy shear and bending forces.Extending the top cap strip forward to the leading edge would have added strength to the entering edge with a minimal weight penalty. Some officers believed that the wing's leading edge stuck out too far forward of the main spar. James Meissner, for one, said this during his appearance before the Congressional Committee in 1919. A postwar caution to airfoil designers held that the leading edge should be as short and rigid as possible. There is some evidence that a secure attachment of the leading edge to the main spar was a more important consideration than the length of the leading edge itself. However, there is no evidence that the Air Service considered these modifications at the time the problems with the Nieuport 28's upper wings occurred.


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Poor wartime workmanship and materials were also contributing factors. During the restoration of a Nieuport 28 at the National Air & Space Museum's Paul Garber Facility, we found evidence of carelessly driven nails in examples of original wing ribs that weakened the rib and, also, minimal use of casein glue (a derivative of milk curd) that is not waterproof.

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Last edited by ArisFuser; 08/20/18 09:04 AM.