Month in the Patent Office

In a control surface of the type in which a balance portion extends directly in front of the control surface pivots, the pivots are carried by tubes, rods or other shallow members projecting out from the fixed part on which the surface is mounted and the leading edge of the surface is formed with gaps to receive the shallow members, cover pieces being provided to close each of the gaps in the leading edge of the control surface except for a clearance which permits of angular adjustment and which is screened by the fixed part. As applied to an aileron carried in an inset portion of a wing a, Figs. 1 and 2, the attaching means comprises a rearwardly projecting tube b having a lug b1 at its rear end adapted to receive a pivot pin b2 for bracket b3 secured to aileron spar b4. The aileron comprises a number of former ribs of which one c2 is located near each tube b, a short false rib c3 being disposed near to and on the opposite side of tube b. A gap is formed in the outer covering between ribs c2 nad c3 which gap is closed except for a clearance c1 by readily detachable cover plates d2, d3, respectively which are secured at their front ends by pins d engaging in key‐hole slots d1. The rear ends of plates d2, d3 are secured to ribs c2, c3 by engagement of curved ends e of springs rods e1, e2 in eyelets d5 formed in the plates. Fig. 3 shows a modified securing means.