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Choosing the optimal materials for a particular task required the analysis of each area of the aircraft to identify the best materials, given the operational environments and stresses a particular part will experience during its lifetime. Aluminium, for example, is susceptible to tensile stress, but can handle pressure very well. Extended use of composite materials, especially in the high voltage environments of the hull, significantly reduce the amount of service required due to tiredness in comparison to an aluminium frame.

When stress indicates that metals are a favoured materials system, but environment aspects indicate that aluminium is a bad option, titan is an outstanding low service construction option. It resists similar stresses better than aluminium, has minimum signs of tiredness and is extremely non-corrosive. The 787's every structure has been subjected to such a lifecycle assessment and the materials are selected through a thorough and rigorous procedure.

Choosing the right materials for the right use. Boeing was able to select the optimal materials for certain aircraft cell deployments without prejudice to pre-conceived notions. Besides reducing the overall aircraft mass, the conversion to a network basic configuration should help to cut down planned and unscheduled airline servicing costs.

As well as using a rugged construction in areas susceptible to failure, the 787 was engineered to be just as repairable as today's airline would be repairing an aircraft with bolt down work. They can be just as durable and damage-proof as a metallic one.

Reduce planned servicing. The Boeing 777 has shown that compound structure needs less planned servicing than non-assembled one. The 777 compound tail, for example, is 25 per cent bigger than the 767?ser aluminium cock, but needs 35 per cent less planned work. These reductions in working time are due to the lower risks of carbon fibre reinforced plastics becoming corrosive and fatiguing in comparison to metals.

Non-routine service reduction. Compound structures also lead to less non-routine servicing. 777 base is made entirely of composites and underlines the benefits of this product when used in a rugged area. Airlines are conscious of the difficulty of stress fractures and corrosive attack that occur with conventional aluminium flooring. For more than 10 years, the 777 has been in service with more than 565 aircraft in the aircraft fleets and has not yet superseded a Single Carrier.

It has also rigorously applied a aluminium use assessment procedure that incorporates the probability of corrosive action combined with the effect of corrosive action. The assessment system provides a definite action to determine an appropriate use of aluminium in designs with a full comprehension of the impact on MRO. Contamination and structural exhaustion contribute significantly to the non-routine service load of an user.

Non-routine servicing often double d or tripled the overall working time spent during a service inspection. Boeing anticipates that with the increased use of compound materials and titan in combination with a greater degree of aluminium expertise, the 787 will have significantly lower non-routine labour cost than a more traditional metal cell. Furthermore, carriers have the ability to repair compound materials that provide an enhanced surface aerodynamics and aesthetics.

Whereas a common compound turnaround may take 24 aircraft down-time or more, Boeing has used the characteristics of compound materials to create a new set of turnaround turnaround capabilities that take less than an entire hour. Fast compound material repairs offer the possibility of a transient reparation to quickly get an aircraft back into shape despite small damages that could cause an aluminium aircraft to leak.