Large-scale static investigation of circulation-control-wing concepts applied to upper surface-blowing aircraft

The use of a circulation control to deflect turbofan engine thrust beyond 90 deg. has been proven in full-scale static ground tests of the circulation-control-wing/upper-surface-blowing (CCW/USB) concept. This powered high-lift system employs a circular, blown trailing edge to replace the USB mechanical flaps to entrain engine-exhaust flow, and to obtain both a vertical-thrust component and an augmented circulation lift for short takeoff and landing (STOL) applications. Previous tests (Phase 1), done in 1982, of a basic configuration installed on the Quiet Short Haul Research Aircraft confirmed these CCW/USB systems capabilities. A second phase (Phase 2) of full-scale, static, thrust-deflection investigations has reconfirmed the ability to deflect engine thrust from 40 to 102 deg., depending on thrust level. Five new configurations were evaluated and performance improvements noted for those configurations with larger blown span, fences or favorable engine interactions, smaller slot height, and larger radii with less than 180 deg. of CCW surface arc. In general, a 90 deg. circular arc with a smaller slot height provided the best performance, demonstrating that adequate thrust turning can be produced by a trailing-edge shape which may have minimal cruise-performance penalty. Thrust deflections were achieved at considerably lower blowing momentum than was required for the baseline case of Phase 1. Improved performance and versatility were thus confirmed for the CCW/USB system applied to STOL aircraft, where the potential for developing a non-moving-parts pneumatic thrust deflector to rapidly vary horizontal force from thrust to drag, while maintaining constant vertical force, appears quite promising. The conversion from high-lift to lower-drag cruise mode by merely terminating the blowing provides an effective STOL aircraft system

Static investigation of the circulation control wing/upper surface blowing concept applied to the quiet short haul research aircraft

Full scale static investigations were conducted on the Quiet Short Haul Research Aircraft (QSRA) to determine the thrust deflecting capabilities of the circulation control wing/upper surface blowing (CCW/USB) concept. This scheme, which combines favorable characteristics of both the A-6/CCW and QSRA, employs the flow entrainment properties of CCW to pneumatically deflect engine thrust in lieu of the mechanical USB flap system. Results show that the no moving parts blown system produced static thrust deflections in the range of 40 deg to 97 deg (depending on thrust level) with a CCW pressure of 208,900 Pa (30.3 psig). In addition, the ability to vary horizontal forces from thrust to drag while maintaining a constant vertical (or lift) value was demonstrated by varying the blowing pressure. The versatility of the CCW/USB system, if applied to a STOL aircraft, was confirmed, where rapid conversion from a high drag approach mode to a thrust recovering waveoff or takeoff configuration could be achieved by nearly instantaneous blowing pressure variation

Diagnosis, treatment and outcome of pheochromocytoma in a cat

Pheochromocytoma in cats is a rare clinical condition characterised by the development of a secretory endocrine tumour that arises from the adrenal medulla. An 8-year-old castrated male, domestic shorthair cat was referred for further investigation of a 4-month history of progressive weight loss with normal appetite, polyuria/polydipsia, generalised weakness, and severe hypertension. Sonography and computed tomography of the abdomen disclosed a mass arising from the left adrenal gland. The contralateral adrenal gland was normal in size and shape. Results from a low dose dexamethasone suppression test and measurements of plasma aldosterone concentration and plasma renin activity ruled out a cortisol-secreting tumour and aldosteronoma. The clinical presentation made a sex-steroid secreting tumour unlikely. Increased plasma metanephrine and normetanephrine concentrations prioritised the differential diagnosis of pheochromocytoma. The cat underwent adrenalectomy of the left gland and histopathological diagnosis with immunohistochemical markers confirmed the diagnosis

Review of Issues Associated with Safe Operation and Management of the Space Shuttle Program

At the request of the President of the United States through the Office of Science and Technology Policy (OSTP), the NASA Administrator tasked the Aerospace Safety Advisory Panel with the responsibility to identify and review issues associated with the safe operation and management of the Space Shuttle program arising from ongoing efforts to improve and streamline operations. These efforts include the consolidation of operations under a single Space Flight Operations Contract (SFOC), downsizing the Space Shuttle workforce and reducing costs of operations and management. The Panel formed five teams to address the potentially significant safety impacts of the seven specific topic areas listed in the study Terms of Reference. These areas were (in the order in which they are presented in this report): Maintenance of independent safety oversight; implementation plan for the transition of Shuttle program management to the Lead Center; communications among NASA Centers and Headquarters; transition plan for downsizing to anticipated workforce levels; implementation of a phased transition to a prime contractor for operations; Shuttle flight rate for Space Station assembly; and planned safety and performance upgrades for Space Station assembly. The study teams collected information through briefings, interviews, telephone conversations and from reviewing applicable documentation. These inputs were distilled by each team into observations and recommendations which were then reviewed by the entire Panel

Cal Poly\u27s AMELIA 10 Foot Span Hybrid Wing-Body Low Noise CESTOL Aircraft Wing Tunnel Test and Experimental Results Overview

A collaboration between California Polytechnic Corporation with Georgia Tech Research Institute (GTRI) and DHC Engineering worked on a NASA NRA to develop predictive capabilities for the design and performance of Cruise Efficient, Short Take-Off and Landing (CESTOL) subsonic aircraft. The work presented in this paper gives details of a large scale wind tunnel effort to validate predictive capabilities for this NRA for aerodynamic and acoustic performance during takeoff and landing. The model, Advanced Model for Extreme Lift and Improved Aeroacoustics {AMELIA), was designed as a 100 passenger, N+2 generation, regional, cruise efficient short takeoff and land (CESTOL) airliner with hybrid blended wing-body with circulation control. AMELIA is a 1/11 scale with a corresponding 10ft wing span. The National Full-Scale Aerodynamic Complex (NFAC) 40ft by 80ft wind tunnel was chosen to perform the large-scale wind tunnel test. The NFAC was chosen because both aerodynamic and acoustic measurements will be obtained simultaneously, the tunnel is large enough that the downwash created by the powered lift did not impinge on the tunnel walls, and the schedule and cost fit into Cal Poly\u27s time frame and budget. Several experimental measurement techniques were used to obtain the necessary data to validate predictive codes being developed as apart of this effort: along with the traditional forces and moments measurements, stationary microphones were used to obtain far-field acoustic measurements including a 48 element phased array, the Fringe-Image Skin Friction (FISF) technique was used to measure the global skin friction on the wing, surface mounted steady and unsteady pressure transducers were used to obtain local pressure distributions over the model, and oil and smoke flow visualization techniques were employed to understand the effects of the powered lift system in AMELIA. The paper gives a brief summary of AMELIA\u27s performance for variable tunnel speed, momentum mass flow, engine simulator height, and angle of attack