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In the past, commercial airplane manufacturers have used analytical techniques and nonstructured pilot opinion for workload assessment. Analytic techniques are of particular value to the aircraft manufacturer since they offer both the potential for identifying and correcting workload problems early in the design phase when the cost of change is relatively low and a tool that can provide data for certification. One disadvantage to the available analytic techniques is their lack of fidelity in assessing mental effort. With the current shift of flight deck design placing more mental demands on the flightcrew, workload assessment has taken on a new challenge. The addition of formalized subjective measures to traditional objective analyses can provide information that validates the analytic- and simulation-based estimates of physical workload and enhances estimates of mental workload.

A transport airplane fuselage section with a full complement of cabin seats and anthropomorphic test dummies was longitudinally impact tested at a condition that approached the ultimate strength of the airframe protective shell structure. Airframe structural responses, seat/floor reaction loads, and the interactive effects of secondary impacts between multiple cabin seat rows were investigated. The scope and conduct of the test are presented together with some preliminary analyses of the test results.

Since the advent of jet freighter aircraft in the 1960s, a great deal of attention has been placed on the future of air freight and particularly on the aircraft that will carry it. Studies for the “ultimate” optimized air freighter have been many and varied. Concepts have generally been market oriented, aircraft oriented, or ground systems oriented. The base for these studies has been so broad that a set of requirements for a new generation of freighter aircraft and supporting ground systems has not been finalized, and the development funds therefore have not been allocated. This paper discusses some of the possible aircraft and ground systems concepts that might satisfy the future market, the parametric and specific studies that led to these concepts, and the economic constraints that will have to be overcome if the true market potential of air freight is ever to be realized.

Hollow fiber membrane reactors (HFMBRs) may be used for biological wastewater treatment, and may be integrated with NASA's current research developments. The goal of this paper is to (a) evaluate the effect of mass transfer and hydrodynamics in a microporous HFMBR and (b) appropriateness of HFMBRs for use in space applications. Even though bubble-less aeration was not achieved by the use of microporous membranes, mass transfer within the HFMBR was found to increase after biofilm formation. Conversely, convective flow dominated transport within the system. Despite the high treatment efficiency obtained by the HFMBR, due to the bioreactor size, configuration and membrane spacing within the HFMBR, the bioreactor was not a suitable option for application under microgravity conditions. Even though developing a system with more favorable system hydrodynamics would aid in treatment efficiency, the use of a microporous HFMBR is not a recommended option to meet NASA's needs.

The design of VTOL aircraft involves infinitely more problems than does the conventional airplane. Although experience with conventional subsonic craft provides some criteria, the VTOL characteristics require new concepts to determine configuration, payload, range, capability, and reliability. This paper reviews experience and research up to this time and describes design problems together with possible solutions.

We measured the isothermal transmission of two binary mixtures of hydrocarbons through an adsorber bed at 25°C packed with crosslinked polystyrene beads. Transmission is the ratio of the outlet to the inlet concentration. Interference between co-adsorbing gases is manifested by a reduction of the adsorption capacity of each component in the mixture from that obtained in a single-component experiment and by a transmission greater than unity for the weaker-adsorbing component until the stronger-adsorbing component elutes. Binary mixtures of n-butane and propane at 25°C reveal both interference phenomena, whereas binary mixtures of n-butane and 1,3-butadiene at 25°C with concentrations from ~ 1000 to 5000 ppm do not reveal the “overshoot” phenomena.

The Air Force Space Systems Division's continued development of equipments for the space program is producing problems in engineering for transportability that are even more challenging than those faced in the development of the missile family. The large solid rocket motor (SRM) program's experience in 120-156 in. solid motor transportation and handling will be outlined in this paper. The current state-of-the-art and the anticipated requirements for the future will be discussed as well as emphasizing the impact of transportability resolutions upon program management. The measures implemented in the Air Force Systems Command's 375 Series Manuals to integrate the Engineering for Transportability Program into the design engineering process will be summarized.

Solid rocket motors for use in booster stages of launch vehicles in the post-Saturn era may be about 300 in. in diameter and weigh 6,000,000 lb. Machines to transport and handle such large weights do not exist today. This paper conceives and analyzes all practical devices that could be used, and identifies the most economical mode for delivering these motors through the logistic cycle from factory to launch. Specifically examined are pneumatic tire, crawler, and Hovair transporters, cranes, and barges, and associated buildings, roads, and docks. Also discussed is the cost of the logistic system for an assumed program.

The United States Post Office Department is one of the world's largest consolidators of air traffic. Thus, we are deeply interested in exploring the potential for containerization to expedite service, eliminate damage, and reduce terminal handling costs. The conventional mail sack holding about 35 pounds is ideal for use in existing multi-floor postal facilities where use of conveyor belts and slides minimizes mail traffic on workroom floors. However, studies are being made of the need for construction of single floor facilities and the potential for increasing density and facilitating automation by changes in mail dispatching techniques. The Department considers rigid containers and pallets as carrier facilities, but recognizes that their optimum use requires solution of many problems affecting rates, service, cost, and division of mail traffic between air carriers.

A mobile space laboratory must provide a crew with a completely self-contained environment to meet basic crew life support needs. Beyond basic life support the vehicle must also address operational requirements for a variety of possible research projects that may be planned for during a mission. An environment that can react to the passage of time and the changing nature of the mission is crucial to the interior architecture and design. This project presents the design of a mobile and modular space guided by the purpose of the mission and the needs of the crew. A review of precedents offers a basis for the comparison of functional criteria and design approaches. The combined design process contributes to the development of a concept for a planetary mobile workstation.

As the construction of an International Space Station approaches reality, the next phases in the exploration of Space will require long duration missions to the Moon, Mars, and beyond. The risk of traumatic injury and death will be an ever present factor in near space (within our solar system). Reviews of trauma deaths have consistently found that the greatest reduction in preventable death will occur by addressing definitive airway management, treatment of hemothorax and pneumothorax, and control of intra-abdominal hemorrhage. On a long duration space voyage realistic capabilities exist to potentially manage the first two injuries of this triad. The ability to manage a patient requiring operative control of an abdominal injury represents a quantum leap in commitment, but provides a new standard to target in surgical support of the ongoing exploration of space.

The demand of fulfilling the increasing requirements to shorten development lead times force suppliers to enhance modularity and flexible applicability of their machinery component portfolio. The presented examples show how basically similar machinery components, i.e. traveling column systems, can be applied for significantly different types of applications in the aircraft industry. Application examples are shown for drilling and installation of two-piece and blind rivet fasteners on box-type and barrel-type aircraft structures at Airbus Deutschland. It is shown how the basic drilling/riveting system is integrated into assembly stations and assembly lines and how it adapts to the varying operational requirements of A380 and A400M.

In view of the disposal charges for electroplating waste treatment sludges, clean effluent water is only part of the waste treatment problem. US Air Force laboratory studies have shown the chromium reduction chemical used in treatment can drastically effect the volume of sludge produced. Ferrous and sulfide, when properly proportioned, have a catalytic effect which can reduce the volume of sludge from hexavalent chromium reduction reactions by 70-percent compared to acidic reduction with ferrous sulfate. Also, sodium borohydride has successfully reduced the sludge produced from mixed metal wastewater treatment by nearly 80-percent (e.g. 985 mg/1 to 220 mg/1). Both technologies are curently being tested in a 10-gallon per minute demonstration plant at an Air Force maintenance center.

PREFACE There always is a first time. There need not be a second. Many articles have been written to shake persons from a lethargy, or as might be better stated, to keep them from getting into a state of lethargy. The latter is the author's intent for this article. We apparently have not as yet learned the art of extending our total knowledge. We can accomplish complex and brilliant basic designs but then we miss some detail point, and the principle of that point missed may have been known for years. We can, and have, learned to profit by others experience. But not consistently. We have avoided repeating the difficulties of others. But there are times we miss. If this prior information or these experiences are not continually passed along to each and every one, then all cannot benefit and some must of necessity repeat the experiences of others. Some new person or group will then run the gamut, experience the same pitfall.

The effects of microbial fouling on treatment bed (TB) performance are being studied. Fouling of activated carbon (AC) and ion exchange resins (IEX) by live and devitalized bacteria can cause decreased capacity for selected sorbates with AC and IEX TB. More data are needed on organic species removal in the trace region of solute sorption isotherms. TB colonization was prevented by nonclassical chemical disinfectant compositions (quaternary ammonium resins) applied in suitable configurations. Recently, the protection of carbon beds via direct disinfectant impregnation has shown promise. Effects (of impregnation) upon bed sorption/removal characteristics are to be studied with representative contaminants. The potential need to remove solutes added or produced during water disinfection and/or TB microbiological control must be investigated.

LASC-GEORGIA operates a large aircraft assembly plant located in Marietta, Georgia. This facility is owned by the U. S. Government and is known as Air Force Plant No. 6. As a part of the assembly operation, various metallic structures have metal finishes applied to them. Some of these parts are plated. A large portion of the parts are aluminum and may receive anodize or conversion coating finishes. Both the plating and aluminum finishing operations generate waste water that must be treated to meet National Pollution Discharge Elimination System (NPDES) discharge limits.

A submerged membrane biological reactor (MBR) was evaluated for treatment of a spacecraft wastewater analog. The aerobic MBR (a modified CSTR) had a 12 L working volume, submerged 0.2 μm membrane filter, 12.6 h hydraulic retention time (simulated 2 person crew), and infinite solids retention time. Simulated graywater contained a urine analog and two surfactants: disodium cocoamphodiacetate and sodium laureth sulfate (461 ppm of active ingredient, combined). Two MBR runs of 60- and 10-day durations were completed with different conditions (startup: 16 d vs. 3 d, pH control vs. none). Influent, effluent, and mixed liquor were analyzed for COD, BOD, TSS, surfactant concentration, and microbial load and activity. BOD removal averaged ≥ 92% for each run with 100% surfactant degradation but no detectable nitrification. The food to mass (F/M) ratio decreased over time. Surfactant decomposition is feasible with a small-scale MBR, although changes are needed to promote nitrification.

Traditionally, transonic wing design focuses on tailoring of pressure distributions, with little attention paid to spanwise lift distribution. While off-design considerations may constrain the span loading, it is useful nonetheless to know the optimal span loading. Further, induced drag minimization is useful for integration of other components with the wing, such as winglets and engine nacelles. An optimization scheme has been developed allowing Trefftz-plane drag minimization on complete aircraft configurations using high-order panel methods and full-potential CFD codes. Two applications of Trefftz-plane drag minimization for component integration are demonstrated.

THE author has written an addendum to his paper: “Future Research on Air-Cooled Aero Engines” delivered in July, 1935. General prophesies are made on airplane performance, types, trends on the number of engines per airplane, engine sizes in airplanes, wing loading, and engine arrangement. His analysis of engine types to complete the desired power range indicates a definite trend toward higher powers The advantages of the use of higher octane fuels are stressed. Mr. Fedden deplores the fact that no development work on compression-ignition aircraft engines is being done in England, and thinks that the 1500-hp. class should be tackled energetically. The comparative qualities of various engine types are discussed. Negative cooling drag is claimed to be possible at airplane speeds of 400 m.p.h. The flat engine is mentioned as a possibility although its use depends on the thickness of the airplane wing.