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This paper presents, chemistry, test data and processing procedures on a non toxic and environmentally friendly chrome-free conversion coating alternative with the same level of adhesion and secondary corrosion resistance as that found in chrome containing conversion coating systems. Test data from military and independent sources will be presented on secondary coating adhesion, electrical conductivity, filiform and neutral salt-spray corrosion resistance as compared to chromate based systems .on magnesium, aluminum and zinc and their respective alloys. The European “RoSH” initiative will not allow for the presence of any hexavalent chromium on imported electrical components as of July first of 2006. Trivalent chromium based systems generate hexavalent chromium due to the oxidation of the trivalent chromium and as such will not be allowed.

This specification covers a zinc alloy in the form of die castings.

The X-38 vehicle will be used to demonstrate the future technology on durable TPS for the CRV. Astrium has produced two large CMC Nose Skirt side panels for the current X-38 configuration. The design of the 3 dimensional curved and large side panels comprises a light-weight, stringer stiffened concept which compensates the thermal expansion by a system of flexible metallic stand-offs. An optimum in flexibility and stiffness to fulfil all requirements had to be found: strong and stiff enough to carry the thermo-mechanical loads, but flexible enough to realise a fastening concept which does not fail due to thermal expansion. The fastening concept has been tested on development test level. Some thermal and mechanical tests on sub-structure level confirmed the design and analysis work of the complete TPS concept.

Over the past two decades, various models of “worst case” solar energetic particle event (SPE) spectra have been proposed in order to place an upper bound on the likely doses to critical body organs of astronauts on missions outside Earth’s geomagnetic field. In this work, direct comparisons of organ dose estimates for various models of “worst case” SPE spectra are made by using the same transport code (BRYNTRN) and the same human geometry model (Computerized Anatomical Man). The calculations are made assuming nominal thicknesses of spacecraft aluminum shielding. Discussions of possible acute exposure responses from these exposures are presented.

This paper reviews today's aircraft wing production assembly methodology and technologies as well as innovative ideas for advancing the high-level wing assembly state-of-the-art. Automated wing assembly systems are only being utilized to rivet/fasten first level subassemblies like panels, spars, and ribs. All other high level assembly tasks are performed manually, incurring associated increases in recurring costs due to production inefficiencies, long lead times, expensive rate tooling, and difficult assembly tasks performed inside small wing compartments. Existing assembly methods, process parameters, and the process characteristics of manual, machine, and man/machine systems provide many opportunities for improving wing assembly.

Due to the part size and technological limitations of the available assembly equipment, traditional wing manufacturing has consisted of a three stage process. Parts are first manually tacked together in an assembly jig, They are then removed from the jig, rotated horizontally and craned into an automated fastening machine. Finally they are removed from the fastening machines and craned to a third station where the manual tacks are removed and the parts are prepped for final wing box assembly. With the advent of electromagnetic riveting (EMR) and the traveling yoke assembly machine this traditional approach has been replaced with single station processing. Wing panels and spars can now be automatically tacked together under continuous clamp up in their assembly jigs using EMR. This eliminates the requirement for disassembly, debur and cleaning required with the manual process.

British Aerospace needed an automated wing riveting system for fastening the A320 wing sections. The E4000 Wing Riveting System was designed and installed at their Airbus factory in Chester, UK and is now in production. It uses a five axis solid yoke with workheads on each end of the yoke. It accurately installs both rivets and lockbolts over the entire wing panel, including offset areas.

Magnesium and its alloys are promising engineering materials with broad potential applications in the automotive, aerospace, and biomedical fields. These materials are prized for their lightweight properties, impressive specific strength, and biocompatibility. However, their practical use is often hindered by their low wear and corrosion resistance. Despite their excellent mechanical properties, the high strength-to-weight ratio of magnesium alloys necessitates surface protection for many applications. In this particular study, we employed the plasma spraying technique to enhance the low corrosion resistance of the AZ91D magnesium alloy. We conducted a wear analysis on nine coated samples, each with a thickness of 6mm, to assess their tribological performance. To evaluate the surface morphology and microstructure of the dual-phase treated samples, we employed scanning electron microscopy (SEM) and X-ray diffraction (XRD).

The purpose of this document is to define: - compensation washer application requirements - recommended materials - washer thickness determination - dimensioning

The purpose of this document is to define: - compensation washer application requirements - recommended materials - washer thickness determination - dimensioning

This specification covers an aluminum alloy in the form of welding wire.

This SAE Aerospace Recommended Practice defines a method for determining the weldability of weld filler metal in continuous coil or cut length form. It is applicable to all solid (non flux-containing) wires. It is intended as a referee method for testing weld filler metals in case of dispute between purchaser and vendor.

The purpose of this document is to define: - compensation washer application requirements - recommended materials - washer thickness determination - dimensioning