7.1 CHANGE AND DISCONTINUANCE NOTIFICATIONS
A typical time line for product discontinuance is shown in Figure 7-2. The part manufacturer will issue a product discontinuance notice (PDN) or product change notice (PCN). The part user then has commonly three to six months in which to place final orders for the original part. The final orders may then be delivered over the following six months to one year. After this date, no more original parts are available from the original part manufacturer, although they may remain available from aftermarket suppliers in some cases.
Component manufacturing companies issue a product discontinuance notice (PDN) when they decide to cease production of a part or replace it with a new part that is sufficiently different to warrant a new part number.
If component manufacturing companies change their products, they issue a product change notice (PCN) to inform their customers about the actual changes to parts.
The impact of a PDN is effectively the same as a PCN when the changes described in a PCN are major, making it impossible to replace the original part with the changed one. Especially in sensitive product sectors (for example, aerospace components), small changes to parts can make requalification of the part or the entire system in which the part is used necessary. The consequence ...