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Currently, the Aviation industry uses traditional methods of communication, coordination, & human interaction to give disposition to resolve any kind of nonconformance occurrences which occur during manufacturing or operation of commercial or defense products. This involves increased in-person interaction and additional travel, especially to address the nonconformance issues arising at supplier plants or airports around the globe. During Covid and post-Covid environments, human interactions for the transfer of detailed information at different & distant manufacturing plant locations has been difficult, since support engineering teams (Example: Liaison, Product Review, Quality, Supplier Quality, and Manufacturing Engineering, and/or Service Engineering) have been working remotely.

The aircraft asset life cycle processes are rapidly being digitalized. Many novel technologies enabled processes of recording these electronic transactions are being emerged. One such technology for recording electronic transactions securely is Blockchain, defined as distributed ledger technologies which includes enterprise blockchain. Blockchain is not widely used in the aerospace industry due to lack of technical understanding and questions about its benefits. Assessment and establishment of business case for implementing blockchain based solution is needed. The aerospace industry is very conservative when it comes to technology adoption and hence it is difficult to change legacy processes. Additionally, the industry is very fragmented. The technology is advancing at a faster rate and applies across geographies under various regulatory oversight which makes blockchain based solution implementation challenging.

For new aircraft production, initial production typically reveals difficulty in achieving some assembly level tolerances which in turn lead to non-conformances at integration. With initial design, tooling, build plans, automation, and contracts with suppliers and partners being complete, the need arises to resolve these integration issues quickly and with minimum impact to production and cost targets. While root cause corrective action (RCCA) is a very well know process, this paper will examine some of the unique requirements and innovative solutions when addressing variation on large assemblies manufactured at various suppliers. Specifically, this paper will first review a completed airplane project (Project A) to improve fuselage circumferential and seat track joins and continue to the discussion on another application (Project B) on another aircraft type but having similar challenges.

This paper addresses the issue of fault diagnosis in the heat exchanger of an aircraft Air Conditioning System (ACS). The heat exchanger cools the air by transferring the heat to the ram-air. Due to a variety of biological, mechanical and chemical reasons, the heat exchanger may experience fouling conditions that reduces the efficiency and could considerably affect the functionality of the ACS. Since, the access to the heat exchanger is limited and time consuming, it is preferable to implement an early fault diagnosis technique that would facilitate Condition Based Maintenance (CBM). The main contribution of the paper is pre-flight fault assessment of the heat exchanger using a combined model-based and data-driven approach of fault diagnosis. A Simulink model of the ACS, that has been designed and validated by an industry partner, has been used for generation of sensor data for various fouling conditions.

This paper presents a PC based mathematical and rapid prototyping technique for anthropometric accommodation in a maintenance environment using the principle of simulation based design. The developed technique is capable of analyzing anthropometric data using multivariate (Principal component Analysis) approach to describe the body size variability of any given population. A number of body size representative cases are established which, when used properly within the constraints of the maintenance environments, will ensure the accommodation of a desired percentage of a population. This technique evaluates the percentage accommodation of a given population for the environment using the specific manikin cases as boundary conditions. In the case where any member of a maintenance crew cannot be accommodated, the technique has the capability of informing the designer of the environment why the member(s) is/are not accommodated.

Jet fighter missions have been known to last extended period of time. The need for a comfortable and safe seat has become paramount considering that fact that uncomfortable seats can lead to numerous health issues. Several health effects like numbness, pressure sore, low back pain, and vein thrombosis have been associated with protracted sitting. The cushion, and of late the installation rail angle are the only components of the ejection seat system that can be modified to reduce these adverse effects. A comprehensive static comfort evaluation study for ejection seats was conducted. It provides comparison between a variety of operational and prototype cushions (baseline cushion, honeycomb and air-cushion) and three different installation rail angles (14°, 18°, and 22°). Three operational cockpit environment mockups with adjustable installation rail angle were built. Ten volunteer subjects, six females and four males, ages 19 to 35, participated in the seat comfort evaluation.

A consortium of interested parties has conducted an experimental characterization of two Tau parallel kinematic machines which were built as a part of the EU-funded project, SMErobot1. Characteristics such as machine stiffness, work envelope, repeatability and accuracy were considered. This paper will present a brief history of the Tau parallel machine, the results of this testing and some comment on prospective application to the aerospace industry.

Boeing has contracts for military application of twin engine airplanes generically identified in this paper as the MX airplane. Unlike previous derivatives, the MX airplanes are produced with a streamlined manufacturing process to improve cost and schedule performance. The final assembly of each MX airplane includes a series of integration tests, called factory functional tests (FFTs), which are modified from those of typical commercial versions and verify correctness of equipment installation and basic functionalities. Two airplanes have been through the production line resulting in a number of FFT lessons learned. Addressed are the power distribution lessons learned: 1) the expanded coverage of the basic automated power-on generation system test, 2) the need for a manual wire continuity test, 3) salient features of the power distribution tests, and 4) keys to make first pass power distribution test smooth and successful.

The repairing of commercial aircraft is a complex task. Service engineers at Boeing's Commercial Aviation Services group specialize in providing crucial repair information and technical support for its many customers. This paper details factors that influence Boeing's response time to service requests and how to improve it. Information pertaining to over 5000 service requests from 2008 and 2009 was collected. From analysis of this data set, important findings were discovered. One major finding is that between 6 and 8 percent of service requests are late because time/date stamps used in reports were created in a different time zone.

After launch and activation activities, the Columbus module started its operational life on February 2008 providing resources to the internal and external experiments. In March 2008 two US Payloads were successfully installed into Columbus Module: Microgravity Sciences Glovebox (MSG) and a US payload of the Express rack family, Express Rack 3, carrying the European Modular Cultivation System (EMCS) experiment. They were delivered to the European laboratory from the US laboratory and followed few months later by similar racks; Human Research Facility 1 (HRF1) and HRF2. The following paper provides an overview of US Payloads, giving their main features and experiments run inside Columbus on year 2008. Flight issues, mainly on the hydraulic side are also discussed. Engineering evaluations released to the flight control team, telemetry data, and relevant mathematical models predictions are described providing a background material for the adopted work-around solutions.

The International Space Station (ISS) program is nearing an assembly complete configuration with the addition of the final resource node module in early 2010. The Node 3 module will provide critical functionality in support of permanent long duration crews aboard ISS. The new module will permanently house the regenerative Environment Control and Life Support Systems (ECLSS) and will also provide important habitability functions such as waste management and exercise facilities. The ISS program has selected the Port side of the Node 1 “Unity” module as the permanent location for Node 3 which will necessitate architecture changes to provide the required interfaces. The USOS ECLSS fluid and ventilation systems, Internal Thermal Control Systems, and Avionics Systems require significant modifications in order to support Node 3 interfaces at the Node 1 Port location since it was not initially designed for that configuration.

The development of the Advanced Life Support (ALS) Sizing Analysis Tool (ALSSAT) using Microsoft® Excel was initiated by the Crew and Thermal Systems Division of the NASA Johnson Space Center (JSC) in 1997 to support the ALS and Exploration Offices in Environmental Control and Life Support System (ECLSS) design and studies. It aids the user in performing detailed sizing of the ECLSS for different combinations of Exploration Life Support (ELS) regenerative system technologies. This analysis tool will assist the user in performing ECLSS preliminary design and trade studies as well as system optimization efficiently and economically.

The Orion Air Monitor (OAM), a derivative of the International Space Station's Major Constituent Analyzer (MCA) (1–3) and the Skylab Mass Spectrometer (4, 5), is a mass spectrometer-based system designed to monitor nitrogen, oxygen, carbon dioxide, and water vapor. In the Crew Exploration Vehicle, the instrument will serve two primary functions: 1) provide Environmental Control and Life Support System (ECLSS) data to control nitrogen and oxygen pressure, and 2) provide feedback the ECLSS water vapor and CO2 removal system for swing-bed control. The control bands for these ECLSS systems affect consumables use, and therefore launch mass, putting a premium on a highly accurate, fast-response, analyzer subsystem. This paper describes a dynamic analytical model for the OAM, relating the findings of that model to design features required for accuracies and response times important to the CEV application.

A habitable atmosphere is a fundamental requirement for human spaceflight. To meet this requirement, the cabin atmosphere must be constantly scrubbed to maintain human life and system functionality. The primary system for atmospheric scrubbing of the US on-orbit segment (USOS) of the International Space Station (ISS) is the Trace Contaminant Control System (TCCS). As part of the Environmental Control and Life Support Systems' (ECLSS) atmosphere revitalization rack in the US Lab, the TCCS operates continuously, scrubbing trace contaminants generated primarily by two sources: the metabolic off-gassing of crew members and the off-gassing of equipment in the ISS. It has been online for approximately 95% of the time since activated in February 2001. The TCCS is comprised of a charcoal bed, a catalytic oxidizer, and a lithium hydroxide post-sorbent bed, all of which are designed to be replaced on-orbit when necessary.

Computational Fluid Dynamics airflow models for the Waste and Hygiene Compartment (WHC) in the U.S. Laboratory module and Node 3 were developed and examined. The International Space Station (ISS) currently provides human waste collection and hygiene facilities in the Russian Segment Service Module (SM) which supports a three person crew. An additional set of Russian hardware, known as the system, is planned for the United States Operational Segment (USOS) to support expansion of the crew to six persons. Integration of the Russian system into the USOS incorporates direct Environmental Control and Life Support System (ECLSS) interfaces to allow more autonomous operation. A preliminary design concept was used to create a geometry model to evaluate the air interaction with the module cabin at varied locations and performance of the avionics fan placed in WHC. The Russian and the privacy protection bump-outs (Kabin) were included into the present modeling.

Solar proton events (SPEs) represent the single-most significant source of acute radiation exposure during space missions. Historically, an exponential in rigidity (particle momentum) fit has been used to express the SPE energy spectrum using GOES data up to 100 MeV. More recently, researchers have found that a Weibull fit better represents the energy spectrum up to 1000 MeV (1 GeV). In addition, the availability of SPE data extending up to several GeV has been incorporated in analyses to obtain a more complete and accurate energy spectrum representation. In this paper we discuss the major SPEs that have occurred over the past five solar cycles (~50+ years) in detail - in particular, Aug 1972 and Sept & Oct 1989 SPEs. Using a high-energy particle transport/dose code, radiation exposure estimates are presented for various thicknesses of aluminum. The effects on humans and spacecraft systems are also discussed in detail.

Effective thermal and micrometeoroid protection as afforded by the Thermal Micrometeoroid Garment (TMG) is critical in achieving safe and efficient missions. It is also critical that the TMG does not increase torque or decreased range of motion which can cause crewmember discomfort, fatigue, and reduced efficiency. For future exploration missions, removable and replaceable TMGs will allow the use of different pressure garment protective covers and TMG configurations for launch, re-entry, 0-G Extra Vehicular Activity (EVA), and lunar surface EVA. A study was conducted with the goal of developing high Technology Readiness Level (TRL), scalable, interface design concepts for TMG systems. The affects of TMG segmentation on mobility and donning were assessed. Closure mechanisms were investigated and tested to determine their operability after exposure to lunar dust. A TMG configuration with the optimum number of segments and location of interfaces was selected for the Mark III spacesuit.

A trade study was conducted with a goal to develop relatively high TRL design concepts for an Exploration Cooling Garment (ExCG) that can accommodate larger metabolic loads and maintain physiological limits of the crewmembers health and work efficiency during all phases of exploration missions without hindering mobility. Effective personal cooling through use of an ExCG is critical in achieving safe and efficient missions. Crew thermoregulation not only impacts comfort during suited operations but also directly affects human performance. Since the ExCG is intimately worn and interfaces with comfort items, it is also critical to overall crewmember physical comfort. Both thermal and physical comfort are essential for the long term, continuous wear expected of the ExCG.

The proliferation and growth of microorganisms in the Internal Active Thermal Control System (IATCS) aboard the International Space Station (ISS) has been of significant concern since 2001. Initial testing and assessments of biocides to determine bacterial disinfection capability, material compatibility, stability (rate of oxidative degradation and identification of degradation products), solubility, application methodology, impact on coolant toxicity hazard level, and impact on environmental control and life support systems identified a prioritized list of acceptable biocidal agents including glutaraldehyde, ortho-phthalaldehyde (OPA), and methyl isothiazolone. Glutaraldehyde at greater than 25 ppm was eliminated due to NASA concerns with safety and toxicity and methyl isothiazolone was eliminated from further consideration due to ineffectiveness against biofilms and toxicity at higher concentrations.

As part of NASA's initiative to develop an advanced portable life support system (PLSS), a baseline schematic has been chosen that includes gaseous oxygen in a closed circuit ventilation configuration. Supply oxygen enters the suit at the back of the helmet, passes over the astronaut's body, and is extracted at the astronaut's wrists and ankles through the liquid cooling and ventilation garment (LCVG). The extracted gases are then treated using a rapid cycling amine (RCA) system for carbon dioxide and water removal and activated carbon for trace gas removal before being mixed with makeup oxygen and reintroduced into the helmet. Thermal control is provided by a suit water membrane evaporator (SWME). As an extension of the original schematic development, NASA evaluated several Helmet Exhalation Capture System (HECS) configurations as alternatives to the baseline.