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The term “3 inch ice shapes” has assumed numerous definitions throughout the years. At times it has been used to generally characterize large glaze ice accretions on the major aerodynamic surfaces (wing, horizontal stabilizer, vertical stabilizer) for evaluating aerodynamic performance and handling qualities after a prolonged icing encounter. It has also been used as a more direct criterion while determining or enforcing sectional ice shape characteristics such as the maximum pinnacle height. It is the authors’ observation that over the years, the interpretation and application of this term has evolved and is now broadly misunderstood. Compounding the situation is, at present, a seemingly contradictory set of guidance among (and even within) the various international regulatory agencies resulting in an ambiguous set of expectations for design and certification specialists.

Boeing needed a process to replace hand drilling for floor panel holes and galley and lavatory mounting locator holes in the floor grid of the completed 737 fuselage. Electroimpact developed a process, and the 737 AFDE machine, that is a substantial improvement over existing technology. It provides full CNC control, quick reconfiguration of hole patterns, fast drilling of up to 3000 holes in one 8-hour shift, drills both titanium and aluminum and works inside the fuselage.

One of the most common damages occurred found on commercial airframes are dents and gouges. The usual repair for these damages includes installation of metallic doublers with rivets or with hi-loks. Sometimes these doublers are of complex design, because of multiple angles of the original damaged skin. Many times the damages are in hard to reach areas. In these cases the traditional metallic doubler repairs are not only time consuming and but also expensive. As the numerous holes are be drilled through the original structure, its fatigue life is adversely affected. For airline operators, time is valuable and they cannot afford to lose revenue by spending longer time for repairs. The use of bonded composite doublers offers the airframe manufacturers and aircraft repair facilities an alternative repair process that alleviates the abovementioned concerns.

Engineering plastics are now available for use on lightly loaded aircraft structure. These materials have excellent cost benefits as well as producibility benefits over their hand laidup predecessors. They are especially useful in the strut and nacelle areas where many of the fairings are attached for aerodynamic purposes only and may have rather complicated contours. In addition to lower costs, the manufacturing process is consistent, unlike hand laidup parts, which often require rework. In the strut and nacelle area one of the major requirements for all parts is sonic durability. This paper is intended to explain the test setup and test procedure for sonic testing of thermoplastics and thermosets and the results of the testing up to this point. Included in this explanation will be the assumptions made, the test setup, results of the testing and conclusions drawn from the testing.

The Boeing Company is striving to improve quality and reduce defects and injuries through the implementation of lightweight “Right Sized” automated drill and fasten equipment. This has lead to the factory adopting Boeing developed and supplier built flex track drill and countersink machines for drilling fuselage circumferential joins, wing panel to spar and wing splice stringers. The natural evolution of this technology is the addition of fastener installation to enable One Up Assembly. The critical component of One Up Assembly is keeping the joint squeezed tightly together to prevent burrs and debris at the interface. Traditionally this is done by two-sided machines providing concentric clamp up around the hole while it is being drilled. It was proposed that for stiff structure, the joint could be held together by beginning adjacent to a tack fastener, and assemble the joint sequentially using the adjacent hole clamp up from the previous hole to keep the joint clamped up.

The use of portable automated equipment has increased in recent years with the introduction of flex track, crawling robots, and other innovative machine configurations. Portable automation technologies such as these lower infrastructure costs by minimizing factory floor space requirements and foundation expenses. Portable automation permits a higher density of automated equipment to be used adjacent to aircraft during assembly. This equipment also allows concurrent work in close proximity to automated processes, promotes flexibility for changes in rate, build plan, and floor space requirements throughout the life of an airplane program. This flexibility presents challenges that were not encountered with traditional fixed machine drilling centers. The work zone surrounding portable machines is relatively small, requiring additional setup time to relocate and position machines near the airframe.

Boeing has relied upon the 767 ASAT (ASAT1) since 1983 to fasten the chords, stiffeners and rib posts to the web of the four 767 wing spars. The machine was originally commissioned with a Terra five axis CNC control. The Terra company went out of business and the controls were replaced with a custom DOS application in 1990. These are now hard to support so Boeing solicited proposals. Electroimpact proposed to retrofit with a Fanuc 31I CNC, and in addition, to replace all associated sensors, cables and feedback systems. This work is now complete on two of the four machines. Both left front and right front are in production with the new CNC control.

Determining local ice crystal icing concentration factors in the region of the forward fuselage is critical for setting the Total Water Content levels for air data probe qualification testing. Simulation, modeling, and testing techniques for this concentration-factor phenomenon are still in their infancy, and there is currently not a significant amount of this type of analysis in the literature. A representative, 3D analysis was conducted using transport airplane geometry and flight conditions that explored the sensitivities resulting from parametric changes to flight and ice crystal icing conditions, particle modeling parameters, and bouncing effects.

The Turret Head Fastening System is an enhancement of current three position “C-frame” wing riveting machines. It was designed and built by Boeing as a fully instrumented research machine in 1991 for the 777 Airplane, and as a potential retrofit package for conventional drill, rivet, shave wing assembly machines. It was designed to automatically install rivets and bolts and perform the required hole preparation prior to fastener installation. In its current form, it will clamp a panel; and then as the fastener requires, drill, coldwork, ream, countersink the hole; inspect the hole; apply sealant when required; install threaded fasteners or rivets; torque the nut, swage the collar or upset the rivet as required; shave the rivet to ensure flushness; and finally unclamp the part - all within the current working envelope of a drill, rivet shave machine. Currently, switching from rivets to bolts requires a 5 minute tool change.