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This paper defines the geometry of minimum weight tank structures of given enclosed volume. A tank structure is considered to comprise a circular cylindrical shell (monocoque or stiffened), bulkheads, and skirt structures. The analyses, starting from established criteria of failure, apply to the loading cases of longitudinal compression and bending moments in combination with internal pressure. The bulkhead geometries are flat, hemispherical, and ellipsoidal. For monocoque shells, the analyses yield the radius and wall thicknesses prescribing a minimum total weight of cylindrical tank wall, bulkheads, and skirts (unpressurized cylindrical appendages, for example, interstage structure). For stiffened shells, the analyses yield the tank radius, skin gauge, stringer spacing, and frame spacing prescribing a minimum total tank weight. An optimum relative geometry is defined for three types of stringers.

Sustainability is both an ethical responsibility and business concern for the aerospace industry. Military and commercial avionics developers have pushed toward a common standard for interfaces, computing platforms, and software in hopes of having “reusability” and reducing weight with backplane computing architectures which, in theory, would support commonality across aircraft systems. The integrated modular avionics (IMA) and military Future Airborne Capability Environment (FACE) standards are two such examples. They emerged to support common computing architectures for reuse and sustainability concepts, from the beginning of aircraft development to the sundown or mortality phase. Pitfalls of Designing, Developing, and Maintaining Modular Avionics Systems in the Name of Sustainability looks at technological, organizational, and cultural challenges making reuse and IMA platform models difficult to fully realize their sustainability goals.

Occupant’s protection requires two design considerations: 1) reduction of decelerations on the occupant (restrained by a belt) by intentional deformability of the structure; 2) limitation of passenger’s compartment deformation to avoid passenger crushing. It is thought that the second trend should have basic importance. It is necessary to ensure a minimum space called “survival space.” This is also necessary in the event of severe crashes. A survey is made of structure deformations due to longitudinal, transversal and vertical loads dynamically or statically applied on trucks cabs and car passenger’s compartments. A high-power static test rig permitting the study of structure is described. Orientative values of the survival space are proposed for truck cabs and car passenger’s compartments.

The Fly-By-Light Advanced Systems Hardware (FLASH) program is developing Fly-By-Light (FBL) and Power-By-Wire (PBW) technologies for military and commercial aircraft. The flight control system portion of FLASH focuses on the integration of fiber optic sensors, optic data buses, actuators (PBW, smart, rotary thin wing) and optic cable plant components for centralized and distributed flight control architectures. Laboratory demonstrations will show applicability to widebody commercial transport and military tactical aircraft. This paper summarizes the requirements, objectives, key technologies and demonstration configurations of each of three FLASH flight control system developments.

This paper documents the vehicle response of a tractor-semitrailer following a sudden air loss (Blowout) in a steer axle tire while traveling at highway speeds. The study seeks to compare full-scale test data to predicted response from detailed heavy truck computer vehicle dynamics simulation models. Full-scale testing of a tractor-semitrailer experiencing a sudden failure of a steer axle tire was conducted. Vehicle handling parameters were recorded by on-board computers leading up to and immediately following the sudden air loss. Inertial parameters (roll, yaw, pitch, and accelerations) were measured and recorded for the tractor and semitrailer, along with lateral and longitudinal speeds. Steering wheel angle was also recorded. These data are presented and also compared to the results of computer simulation models. The first simulation model, SImulation MOdel Non-linear (SIMON), is a vehicle dynamic simulation model within the Human Vehicle Environment (HVE) software environment.

Successful trace chemical contamination control is one of the components necessary for achieving good cabin atmospheric quality. While employing seemingly simple process technologies, sizing the active contamination control equipment must employ a reliable design basis for the trace chemical load in the cabin atmosphere. A simplified design basis that draws on experience gained from the International Space Station program is presented. The trace chemical contamination control design load refines generation source magnitudes and includes key chemical functional groups representing both engineering and toxicology challenges.

Trailing axles, otherwise known as tag axles, are utilized in many states to allow heavy duty dump trucks and cement trucks to maximize their capacity. The trailing axle is an additional axle mounted on an arm on the rear of the truck that can be raised and lowered. When lowered, the axle extends the overall wheelbase of the vehicle and increases the total number of axles, thereby allowing for additional load to be carried without exceeding load-restriction regulations. There are multiple manufactures of trailing axles that utilize different suspension designs. One design uses an articulating axle that is mounted to the framework that lowers it. In this study, the sensitivity of this design to tire blowout on one of the trailing axle tires is studied. Testing was conducted that involved initiating a sudden air-loss event by creating a hole in the sidewall of the tire. The handling response of the vehicle was documented with on-board instrumentation and on-board and off-board video.