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Aerospace structures manufacturers find themselves frequently engaged in large-scale 3D metrology operations, conducting precision measurements over a volume expressed in meters or tens of meters. Such measurements are often done by metrologists or other measurement experts and may be done in a somewhat ad-hoc fashion, i.e., executed in the most appropriate method according to the lights of the individual conducting the measurement. This approach is certainly flexible but there are arguments for invoking a more rigorous process. Production processes, in particular, demand an automated process for all such “routine” measurements. Automated metrology offers a number of advantages including enabling data configuration management, de-skilling of operation, real time input data error checking, enforcement of standards, consistent process execution and automated data archiving. It also reduces training, setup time, data manipulation and analysis time and improves reporting.

Fabrication and assembly of the majority of control surfaces for Boeing’s 777X airplane is completed at the Boeing Defense, Space and Security (BDS) site in St. Louis, Missouri. The former 777 airplane has been revamped to compete with affordability goals and contentious markets requiring cost-effective production technologies with high maturity and reliability. With tens of thousands of fasteners per shipset, the tasks of drilling, countersinking, hole inspection, and temporary fastener installation are automated. Additionally and wherever possible, blueprint fasteners are automatically installed. Initial production is supported by four (4) Electroimpact robotic systems embedded into a pulse-line production system requiring strategic processing and safeguarding solutions to manage several key layout, build and product flow constraints.

A dual-membrane gas trap is currently used to remove gas bubbles from the Internal Thermal Control System (ITCS) coolant on board the International Space Station (ISS). The gas trap consists of concentric tube membrane pairs, comprised of outer hydrophilic tubes and inner hydrophobic fibers. Liquid coolant passes through the outer hydrophilic membrane, which traps the gas bubbles. The inner hydrophobic fiber allows the trapped gas bubbles to pass through and vent to the ambient atmosphere in the cabin. The gas trap was designed to last for the entire lifetime of the ISS, and therefore was not designed to be repaired. However, repair of these gas traps is now a necessity due to contamination from the on-orbit ITCS fluid and other sources on the ground as well as a limited supply of flight gas traps. This paper describes a novel repair technique that has been developed that will allow the refurbishment of contaminated gas traps and their return to flight use.

Low rate initial production of the 777X flight control surfaces and wing edges has been underway at the Boeing St. Louis site since early 2017. Drilling, inspection, and temporary fastening tasks are performed by automated multi-function robotic systems supplied by Electroimpact. On the heels of the successful implementation of the initial four (4) systems, Phases II and III are underway to meet increasing production demands with three (3) and four (4) new cells coming online, respectively. Assemblies are dedicated to particular cells for higher-rate production, while all systems are designed for commonality offering strategic backup capability. Safe operation and equipment density are optimized through the use of electronic safeguards. New time-saving process capabilities allow for one-up drilling, hole inspection, fastening, fastener inspection, and stem shaving.

This paper identifies an approach to the definition of a National Airspace System (NAS) architecture which will support the future development of the U.S. air transportation system, consistent with long-range needs of the various users of the NAS. The approach outlined identifies the development of an FAA preliminary design methodology, with supporting tools and processes to provide the basis for NAS modernization. This approach begins with the quantification of the primary long-range objectives of the NAS, which the system architecture must support over its design life. These objectives are the basis of the mission analysis and requirements development, which, in turn, are used for technology tradeoff studies and the baselining of an architecture for evaluation.

Automated fiber placement of pre-impregnated (pre-preg), thermoset carbon materials has been industrialized for decades whereas dry-fiber carbon materials have only been produced at relatively low rates or volumes for large aerospace structures. This paper explores the differences found when processing dry-fiber, thermoset, carbon materials (DFP) as compared to processing pre-preg, thermoset materials with Automated Fiber Placement (AFP) equipment at high rates. Changes to the equipment are required when converting from pre-preg to dry fiber material processing. Specifically, the heating systems, head controls, and tow tension control all must be enhanced when transitioning to DFP processes. Although these new enhancements also require changes in safety measures, the changes are relatively small for high performance systems. Processing dry fiber material requires a higher level of heating, tension control and added safety measures.

Currently scheduled to be delivered to the International Space Station (ISS) in 2009, Crew Quarters (CQs) will be installed in the Node 2 Module. The CQs provide crewmembers with private space, a place to sleep, and minimal storage. Analysis is to be performed to determine if the United States Operational Segment (USOS) Node 2 can maintain temperature between 47°C and 62°C (65°F and 80°F) [units are CCGS with U.S unit in parenthesis] within the CQ. The analysis will concentrate on the nominal hot environmental case. Environmental heat is due to solar heating of the external shell of the ISS. Configurations including both three and four CQs are examined, as well as multiple configurations of the Low Temperature Loop (LTL) that flows through the Node 2 Common Cabin Air Assembly (CCAA). This paper describes the analysis performed to determine if Node 2 will be able to maintain cabin temperature between 47°C and 62°C (65°F and 85°F).

In order to conserve mass and volume, it was proposed that the International Space Station (ISS) control the level of carbon dioxide (CO2) in the Space Shuttle Orbiter while the Orbiter is docked to the ISS. If successful, this would greatly reduce the number of lithium hydroxide (LiOH) canisters required for each ISS-related Orbiter mission. Because of the impact on the Orbiter Environmental Control and Life Support Subsystem (ECLSS), as well as on the Orbiter flight manifest, a Space Shuttle Program (SSP) analysis was necessary. STS-108 (ISS UF1) pre-flight analysis using the Personal Computer Thermal Analyzer Program (PCTAP) predicted that the ISS would be able to control the level of CO2 in the Orbiter (and throughout the stack) under nominal conditions with no supplemental LiOH required. This analysis assumed that the Carbon Dioxide Removal Assembly (CDRA) located in the U.S.

In August 1997 NASA/Marshall Space Flight Center (MSFC) began a test with the objective of monitoring the growth of microorganisms on material simulating the surface of the International Space Station (ISS) Temperature and Humidity Control (THC) Condensing Heat Exchanger (CHX). The test addressed the concerns of potential uncontrolled microbial growth on the surface of the THC CHX subsystem. For this study, humidity condensate from a closed manned environment was used as a direct challenge to the surfaces of six cascades in a test set-up. The condensate was collected using a Shuttle-type CHX within the MSFC End-Use Equipment Testing Facility. Panels in four of the six cascades tested were coated with the ISS CHX silver impregnated hydrophilic coating. The remaining two cascade panels were coated with the hydrophilic coating without the antimicrobial component, silver. Results of the fourteen-month study are discussed in this paper.

The OVERFLOW chimera grid Navier Stokes code was used to analyze a wide variety of airplane configurations. The code performed reliably and was found to have comparable accuracy to the structured grid code TLNS3D. It is easier to develop overlapping grid blocks to represent a complex configuration than it is to develop grid blocks that must abut one another. The process is inherently modular. One can add or subtract components like tip-lights, compound winglets, struts, nacelles, tails and fairings at will. The gain in grid simplicity is offset by the complication in specifying block connectivity, however. The overset blocks are typically of better quality, but there is a drawback in that it is not always possible to guarantee flux conservation. The recent development of software for automatic connectivity holds promise for the routine use of OVERFLOW by design engineers.

Choosing the best approach to meet waste processing requirements for long duration space missions should be based on objective selection criteria that provide for subsystem operational availability at the lowest mission cost. Suitable criteria would include robustness, safety, and the minimization of mass, volume, power, cooling, crew time, and resupply requirements for the candidate technologies. The best candidate technologies based on data from historical missions and preliminary data from the Solid Waste Processing and Resource Recovery Workshop (SWPRRW) have been evaluated for cost effectiveness in processing crew waste loads as defined by identified waste models. Both PC and biological approaches were considered for each of three missions: the ISS mission, a Mars transit mission, and a “concentrated exploration” mission for the Mars surface. Results of this analysis are consistent for all three missions considered.

In many existing AFP cells manual inspection of composite plies accounts for a large percentage of production time. Next generation AFP cells can require an even greater inspection burden. The industry is rapidly developing technologies to reduce inspection time and to replace manual inspection with automated solutions. Electroimpact is delivering a solution that integrates multiple technologies to combat inspection challenges. The approach integrates laser projectors, cameras, and laser profilometers in a comprehensive user interface that greatly reduces the burden on inspectors and decreases overall run time. This paper discusses the implementation of each technology and the user interface that ties the data together and presents it to the inspector.

Wing and fuselage aircraft structures require large precise tools for assembly. These large jigs require periodic re-certification to validate jig accuracy, yet metrology tasks involved may take the tool out of service for a week or more and typically require highly specialized personnel. Increasing the time between re-certifications adds the risk of making out-of-tolerance assemblies. How can we reduce jig re-certification down time without increasing the risk of using out-of-tolerance tooling? An alternative, successfully tested in a prototype tool, is to bring automated metrology tools to bear. Specifically, laser tracker measurements can be automated through a combination of off-the-shelf & custom software, careful line-of-sight planning, and permanent embedded targets. Retro-reflectors are placed at critical points throughout the jig. Inaccessible (out of reach) tool areas are addressed through the use of low cost, permanent, shielded repeatability targets.

One of the largest advancements in the use of the Flextrack technology is the addition of automated fastener installation on the Multifunction Flextrack made by Electroimpact. The new Flextrack installs SSTF (Single Sided Temporary Fasteners) into the holes it drills without removing clamp-up force from the workpiece. This is the first Flextrack to drill and install fasteners and its functionality goes beyond even these functions. The fasteners, SSTF bolts, are increasingly replacing more cumbersome and manual tools for temporary fastening of aerospace components during assembly. They provide doweling, clamp-up, and feature a compact head to facilitate machine installation. The new Multifunction Flextrack carries the bolts on the machine head as opposed to being fed through a feed tube. A Bolt Cartridge System carries up to 80 bolts onboard the Flextrack and the Cartridges can be quick changed for use with several different diameters.

Single Sided Slave Fasteners (SSSF) or Single Sided Temporary Fasteners (SSTF) are increasingly replacing more cumbersome and manual tools for temporary doweling and clamping of aerospace components during assembly. Their ability to clamp provide doweling and clamping reduce the amount of tooling required. Due to their low profile and blind (one-sided) capability, the key benefit of this new technology is the ability to install these fasteners with automated machines. Electroimpact has developed machines to feed primarily SSTF bolts made application-specific by Centrix LLC [ 1 ]. The application discussed in this paper presented problems of confined spaces where a variety of fasteners were required to be fed automatically. To address this, Electroimpact developed new Bolt Injector and Bolt Inserter technology to feed multiple diameters of SSTF bolts in a very small package. Application-specific SSTF were designed such that multiple diameters could be fed through one feed tube.

The automation cycle time of wing assembly can be shortened by the automated installation of single-sided temporary fasteners to provide temporary part clamping and doweling during panel drilling. Feeding these fasteners poses problems due to their complexity in design and overall heavy weight. In the past, Electroimpact has remotely fed these fasteners by blowing them through pneumatic tubing. This technique has resulted in occasional damage to fasteners during delivery and a complex feed system that requires frequent maintenance. Due to these issues, Electroimpact has developed a new fully automated single-sided temporary fastening system for installation of the LISI Clampberry fasteners in wing panels for the C919 wing factory in Yanliang, China. The feed system stores fasteners in gravity-fed cartridges on the end effector near the point of installation.

A significant step is achieved on the flight control actuation system toward the more electrical aircraft through the Airbus A380, A400M and the A350 development phase ongoing. The A380/A400M/A350 features a mixed flight control actuation power source distribution, associating electrically powered actuators with conventional FlyByWire hydraulic servocontrols. In the scope of the preparation of the future Airbus Aircraft, this paper presents the perspectives of the use of the EMA technologies for the flight control systems in the more electrical aircraft highlighting the main technical challenges need to treat: jamming susceptibility, ?on board? maintenance reduction, Operational reliability increase, power electronics and power management optimization, and regarding the environmental constraints, the predicted performances; the benefits associated to the optimized utilization of on-board power sources.

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.

Over 1,200 large diameter holes must be drilled into the side-of-body join on a Boeing commercial aircraft's fuselage. The material stack-ups are multiple layers of primarily titanium and CFRP. Due to assembly constraints, the holes must be drilled for one-up-assembly (no disassembly for deburr). In order to improve productivity, reduce manual drilling processes and improve first-time hole quality, Boeing set out to automate the drilling process in their Side-of-Body join cell. Implementing an automated solution into existing assembly lines was complicated by the location of the target area, which is over 15 feet (4 meters) above the factory floor. The Side-of-Body Drilling machines (Figure 1) are capable of locating, drilling, measuring and fastening holes with less than 14 seconds devoted to non-drilling operations. Drilling capabilities provided for holes up to ¾″ in diameter through stacks over 4.5″ thick in a titanium/CFRP environment.

Traditional Trailing Edge (TE) assembly that utilise fixtures for accurate positioning of aircraft (a/c) parts do not allow for removal of specific tooling from the fixtures to travel with the TE, post assembly. Instead, the tooling that positions all the primary a/c assembly datums generally utilise precision pins of various sizes that index and clamp the a/c ribs. Often it is difficult to remove the pins post assembly before the spar can be taken out of the fixture. Use of hammers is common place to hit pins out of holes which is less than ideal considering the a/c parts can be fragile and the tooling is precision set. Also, the Main Assembly Fixture (MAJ) that will receive the TE will inevitably need to relocate some if not all the primary a/c ribs and therefore will most likely be subject to some amount of persuasion.