When an aircraft required maintenance, mechanics would request the latest engineering drawings for the particular aircraft on which they were working. Library staff would print hard copies of these drawings using aperture card reader/printers. These hard copies would then be distributed to the maintenance technicians. If maintenance was being performed at off-site facilities, hard copies were sent via overnight courier, incurring additional expenses and delays. These delays associated with processing paper drawings resulted in hundreds of thousands of dollars in lost revenue for every day an aircraft was grounded waiting for maintenance