ABSTRACT
Aircraft designs and the levels of technology within them have finite time spans. An essential part of the aircraft selection decision is knowing where the products under consideration are in relation to their product life cycles. Even the most hardened airline scheduling professional will appreciate the need to make fleet provisions beyond the next timetable period, but the reasons for the airline taking a long-term view do not coincide with those of the manufacturer. One of the manufacturer's first tasks in undertaking a fleet planning exercise with an airline is to establish his credibility in proposing what may initially be viewed as an unreasonably long-term solution. Manufacturers have striven to reduce the time from placing an order to delivery. Lead-time for delivery depends upon whether an order is for a brand-new type or merely building on an existing fleet.
