Development of a reduced area horizontal tail for a wide body jet aircraft

Commercial transport aircraft fuel consumption can be significantly reduced by decreasing the size of the horizontal tail. Work on reducing the horizontal tail area of the L-1011 is discussed. The reduced area horizontal tail program consisted of design, fabrication and wind tunnel testing of horizontal tails with reduced planform areas of 30 to 38 percent relative to the standard L-1011 tail. The total drag of the aircraft in cruise was reduced by approximately 2 percent. However, it was necessary to impose forward center of gravity limitations on the aircraft because the maximum lift goal of the reduced area tail was not achieved and sufficient nose-up control authority was not available. On a new design this problem could have been solved by moving the landing gear aft and enlarging the cut-out in the aft fuselage to allow for larger horizontal stabilizer deflections. However, since this is an existing design, these modifications were unfeasible and resulted in the center of gravity restriction

Development of an advanced pitch active control system for a wide body jet aircraft

An advanced PACS control law was developed for a commercial wide-body transport (Lockheed L-1011) by using modern control theory. Validity of the control law was demonstrated by piloted flight simulation tests on the NASA Langley visual motion simulator. The PACS design objective was to develop a PACS that would provide good flying qualities to negative 10 percent static stability margins that were equivalent to those of the baseline aircraft at a 15 percent static stability margin which is normal for the L-1011. Also, the PACS was to compensate for high-Mach/high-g instabilities that degrade flying qualities during upset recoveries and maneuvers. The piloted flight simulation tests showed that the PACS met the design objectives. The simulation demonstrated good flying qualities to negative 20 percent static stability margins for hold, cruise and high-speed flight conditions. Analysis and wind tunnel tests performed on other Lockheed programs indicate that the PACS could be used on an advanced transport configuration to provide a 4 percent fuel savings which results from reduced trim drag by flying at negative static stability margins

The X-33 Program, Proving Single Stage to Orbit

The X-33, NASA's flagship for reusable space plane technology demonstration, is on course to permit a crucial decision for the nation by the end of this decade. Lockheed Martin Skunk Works, NASA's partner in this effort, has led a dedicated and talented industry and government team that have met and solved numerous challenges within the first 26 months. This program began by accepting the mandate that included two unprecedented and highly challenging goals: 1) demonstrate single stage to orbit technologies in flight and ground demonstration in less than 42 months and 2) demonstrate a new government and industry management relationship working together with industry in the lead

Emergency Department Care Transitions for Patients With Cognitive Impairment: A Scoping Review

ObjectivesWe aimed to describe emergency department (ED) care transition interventions delivered to older adults with cognitive impairment, identify relevant patient-centered outcomes, and determine priority research areas for future investigation.DesignSystematic scoping review.Setting and participantsED patients with cognitive impairment and/or their care partners.MethodsInformed by the clinical questions, we conducted systematic electronic searches of medical research databases for relevant publications following published guidelines. The results were presented to a stakeholder group representing ED-based and non-ED-based clinicians, individuals living with cognitive impairment, care partners, and advocacy organizations. After discussion, they voted on potential research areas to prioritize for future investigations.ResultsFrom 3848 publications identified, 78 eligible studies underwent full text review, and 10 articles were abstracted. Common ED-to-community care transition interventions for older adults with cognitive impairment included interdisciplinary geriatric assessments, home visits from medical personnel, and telephone follow-ups. Intervention effects were mixed, with improvements observed in 30-day ED revisit rates but most largely ineffective at promoting connections to outpatient care or improving secondary outcomes such as physical function. Outcomes identified as important to adults with cognitive impairment and their care partners included care coordination between providers and inclusion of care partners in care management within the ED setting. The highest priority research area for future investigation identified by stakeholders was identifying strategies to tailor ED-to-community care transitions for adults living with cognitive impairment complicated by other vulnerabilities such as social isolation or economic disadvantage.Conclusions and implicationsThis scoping review identified key gaps in ED-to-community care transition interventions delivered to older adults with cognitive impairment. Combined with a stakeholder assessment and prioritization, it identified relevant patient-centered outcomes and clarifies priority areas for future investigation to improve ED care for individuals with impaired cognition, an area of critical need given the current population trends