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Unmanned Aerial Vehicles (UAV) are being deployed in military, law enforcement, search & rescue, scientific research, environmental & climate studies, reconnaissance and other commercial and non-commercial applications on a large scale. A design and development of landing gear system has been taken up for a UAV. This paper presents the design optimization of structural components of Wheel-Brake & Fork assembly pertaining to the Main Landing Gear (MLG) for a UAV. The wheel, fork, axle and brake unit constitute the wheel assembly. The wheel-brake assembly is assembled with the strut assembly and forms the Landing gear system. The Fork is the connecting member between the shock strut and the axle containing the wheel-brake assembly. As the fork and axle are subjected to shock loads while landing, the strength of these components are very much essential to withstand the dynamic loads.

Premature wearout of augmentor hydraulic fuel pumps was being experienced in service on a fighter aircraft engine. The removal times ranged from 150 to 800 engine operating hours. Considerable effort had gone into the understanding of the physics of failure and overcoming this problem in a modified pump. However, there still remained the question of how best to proof test the new pump. The challenge was to demonstrate that the redesigned pump was significantly better than the old pump. The problems faced during design verification will be discussed in this case study. For example, does an accelerated test duplicate the service failure mode? When has an accelerated test run long enough to prove the redesign is in fact better than the old product? This paper illustrates the application of new technology to solve these research and development program problems through the use of Weibull and Weibayes Analysis.

RMS (Reliability-Maintainability-Safety-Supportability) engineering is emerging as the newest discipline in product development due to new credible, accurate, quantitative methods. Weibull Analysis is foremost among these new tools. New and advanced Weibull techniques are a significant improvement over the original Weibull approach. This workshop, originally developed by Dr. Bob Abernethy, presents special methods developed for these data problems, such as Weibayes, with actual case studies in addition to the latest techniques in SuperSMITH® Weibull for risk forecasts with renewal and optimal component replacement.

The Environmental Control System (ECS) of an aircraft provides thermal and pressure control of the engine bleed air for comfort of the crew members and passengers onboard. For safe and reliable operation of the ECS under complex operating environments, it is critical to detect and diagnose performance degradations in the system during early phases of fault evolution. One of the critical components of the ECS is the heat exchanger, which ensures proper cooling of the engine bleed air. This paper presents a wavelet-based fouling diagnosis approach for the heat exchanger.

The Water Supply Assembly (WSA) is part of the Liquid Management Section (LMS) of the Hermes Environmental Control and Life Support Subsystem (ECLSS) (see ref. [1] and [2]). The WSA has to provide pure water for drinking and food preparation (rehydratation of dry food and beverage powder) and to provide pure water for hygiene purposes (oral hygiene and towel wetting). To obtain different desired temperatures (as well as different quantities of water to be dispensed), a heating device, using electrical foils, and a cooling device, using a water/water heat exchanger have been designed with regard to the critical mass and power requirements. Two dispensers are used to fill food/beverage or hygiene (towels) containers. As part of the Hermes C1 phase, breadboard models of the heating device (heater) and of the cooling device (chiller) have been manufactured and functionally tested.

This document establishes the minimum requirements for an environmental test chamber, and test procedures to carry out anti-icing performance tests according to the current materials specification for aircraft deicing/anti-icing fluids. The primary purpose for such a test method is to determine the anti-icing endurance under controlled laboratory conditions of AMS1424 Type I and AMS1428 Type II, III, and IV.

This document establishes the minimum requirements for an environmental test chamber, and test procedures to carry out anti-icing performance tests according to the current materials specification for aircraft deicing/anti-icing fluids. The primary purpose for such a test method is to determine the anti-icing endurance under controlled laboratory conditions of AMS1424 Type I and AMS1428 Type II, III, and IV fluids.

This document establishes the minimum requirements for an environmental test chamber, and test procedures to carry out anti-icing performance tests according to the current materials specification for aircraft deicing/anti-icing fluids. The primary purpose for such a test method is to determine the anti-icing endurance under controlled laboratory conditions of SAE AMS1424 Type I and AMS1428 Type II, III, and IV fluids.

This document establishes the minimum requirements for an environmental test chamber, and test procedures to carry out anti-icing performance tests according to the current materials specification for aircraft deicing/anti-icing fluids. The primary purpose for such a test method is to determine the anti-icing endurance under controlled laboratory conditions of AMS 1424 Type I and AMS 1428 Type II, III and IV.

This document establishes the minimum requirements for an environmental test chamber, and test procedures to carry out anti-icing performance tests according to the current materials specification for aircraft deicing/anti-icing fluids. The primary purpose for such a test method is to determine the anti-icing endurance under controlled laboratory conditions of AMS1424 Type I and AMS1428 Type II, III, and IV fluids.

A Suit Water Membrane Evaporator (SWME) system was designed at JSC, NASA, for the Advanced Space Suit Portable Life Support System (PLSS). The SWME was investigated to provide a more robust and reliable method of heat transfer for PLSS heat load, providing an alternate technology to the current Shuttle EMU sublimator. The SWME is less sensitive to water contamination, provides gas venting capability to the PLSS thermal loop, and permits control of heat transfer rate via back pressure regulation. The tests served as a technology demonstration of SWME performance in a concentric, dual-sided design configuration, back pressure regulation under water vapor condition, and combined system compatibility. The tests provided preliminary data to characterize SWME performance and investigate the viability of backpressure regulation control.

Water recovery from wastewater is essential for the success of long term missions. Honeywell Aerospace and the team comprising Thermodistillation Co. (Kiev, Ukraine) and NASA JSC Crew and Thermal Systems Division are developing an advanced wastewater processing subsystem that is based on centrifugal vacuum distillation that will be tested at the NASA JSC water lab. The wastewater processing cascade distillation subsystem (CDS) utilizes a multi-stage thermodynamic process to efficiently produce purified water, and its rotary centrifugal design provides gas/liquid phase separation and liquid transport (pumping) under microgravity conditions. The objective of the program is to demonstrate potable water recovery from various wastewater streams that is suitable to meet the requirements of present (ISS) and future (Lunar-Mars) human space missions. This paper presents the subsystem design and the cascade distiller operational evaluation.

This procurement specification covers plain helical lock washers fabricated from heat treated carbon steel.

An analysis is presented of the relative suitability of sodium, potassium, rubidium, and cesium as working fluids in a high temperature, Rankine Cycle, space power plant. Turbine inlet temperatures of from 1800 to 2000 F with corresponding condensing temperatures of from 1240 to 1530 F are considered. The criteria by which the fluids are evaluated are the thermodynamic cycle characteristics, heat transfer and fluid friction characteristics, metallurgical compatibility, and the influence of the fluids on the design of the turbine, bearings, radiator, generator, and pump. The turbogenerator unit is thought to be the most critical component and it is found that the working fluid will determine the required number of turbine stages and will therefore establish the turbogenerator bearing arrangement. It is not known whether blade erosion will be a problem.

This specification covers a low-alloy steel in the form of welding wire.

This specification covers a low-alloy steel in the form of welding wire.

This specification covers a low-alloy steel in the form of welding wire.

This specification covers a low-carbon steel in the form of welding wire.

This specification covers a low-alloy steel in the form of wire supplied as coils of wire or as finished springs.

This specification covers one type of bronze in the form of round wire 0.500 inch (12.70 mm) and under in nominal diameter.