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Technology developed for the Circulation Control Wing high-lift system has been extended to augment lift by entraining and redirecting engine thrust. Ejecting a thin jet sheet tangentially over a small curved deflecting surface adjacent to the slipstream of a turbofan engine causes the slipstream to flow around that deflecting surface. The angle of deflection is controlled pneumatically by varying the momentum of the thin jet sheet. The downward momentum of the slipstream enhances wing lift. This concept of pneumatically deflecting the slipstream has been applied to an upper surface blowing high-lift system and to a thrust deflecting system. The capability of the pneumatic upper surface blowing system was demonstrated in a series of investigations using a wind tunnel model and the NASA Quiet Short-haul Research Aircraft (QSRA). Full-scale thrust deflections greater than 90 deg were achieved.

The flow-entraining capability of the Circulation Control Wing blown high-lift system has been synergistically combined with upper-surface-mounted engines to provide an even stronger STOL potential. The resulting configurations generate very high supercirculation lift plus a vertical component of pneumatically-deflected engine thrust. Small-scale wind-tunnel and full-scale static thrust-deflection tests have verified these concepts by confirming thrust deflections of greater than 90° produced pneumatically by non-moving aerodynamic surfaces. High lift can be maintained while interchanging thrust recovery and thrust offset for optimum STOL performance, as well as for simplified heavy-lift or overload capability.