My subject is too big to cover adequately in the time at my disposal and as I have been asked to emphasise the wartime experience in aircraft factories, I propose to confine myself to a few of the most interesting problems.

Because of the urgent necessity to produce aircraft quickly in wartime the production engineer has a greater influence on design than normally, and many design problems are usually settled by a compromise between the requirement of the designer and the production engineer.

The designer attempts to satisfy the aerodynamic requirements at the lowest possible weight and the production engineer has to consider the shop equipment and floor space available, the type and availability of labour and ensure that the aircraft can be built in a minimum of man–hours.