Increasing commonality across their models allows commercial aircraft manufacturers to reduce the
product development cycle time and tailor their models to their customers’ needs. The cockpit is an
area where commonality is thought to be particularly desirable, since it also simplifies the pilots
training process for the airline companies. However, no set of metrics is currently able to measure the
efficiency of commonality application at this level from a total lifecycle standpoint.
In this paper, we propose a set of metrics adapted to large commercial aircraft and taking into account
the main parts of the product lifecycle. The concept of lead time is central in our measurement of
commonality, as it strongly influences the value of the aircraft for all primary stakeholders. We
examine the extent to which these metrics are independent from aircraft particularities (such as
physical dimensions). We indicate their limitations and what additional research should be performed
to obtain a set of metrics able to measure the efficiency of commonality implementation for the whole
aircraft.
We use the example of two competing medium-haul aircraft families to test our set of metrics. We
evaluate the efficiency of commonality according to our metrics and we compare with field results
obtained from the manufacturers’ studies and from the results of interviews of airlines pilots. We
show how our se
