Reservisor

Starting in 1946, American Airlines developed a number of automated airline booking systems known as Reservisor. Although somewhat successful, American's unhappiness with the Reservisor systems led them to develop the computerized Sabre system used to this day.

C. R. Smith became president of American Airlines in 1934 and set an aggressive expansion policy. When AA had 85 planes in its fleet he stated "Any employee who can't see a day when we will have a thousand planes had better look for a job somewhere else." Known as a hands-on manager, Smith pushed his vice presidents to drive out inefficiencies that might block their potential expansion.

Following Smith's lead, Marion Sadler, manager of customer support, and Bill Hogan, in charge of finance, concluded that the company was spending too much effort on keeping on top of accounting, and not enough on the problem of booking times. They hired Charles Amman to study the problem. He broke the process down into three steps; finding if a seat was available, updating the seating inventory when they purchased a seat or canceled a booking, and finally recording the passenger data (name, address, etc.) after the sale.

At the time, bookings were handled by a system known as "request and reply". Booking data for any particular flight, say Buffalo to Boston, would be handled by a single office. Here, each scheduled flight was represented by an index card known as a flight card. The offices were normally located at one of airports involved, but was increasingly centralized at major airports or located at a telephone company switching office to ease the adding or removing of phone lines.

In order to book a ticket on a flight, a sales agent would call into the right booking office and request information on a particular flight. The booking agent would then walk over to a filing cabinet and retrieve the flight card. They would then return to the phone to tell the sales agent if there were any seats available. If there was an available seat, they simply checked off a box, informed the sales agent, and returned the card to the cabinet.

Problems occurred when the flights were close to full. In that case the booking agent would have to inform the sales agent that there were no seats, and the sales agent would then ask the customer if there were any other flights they might choose as an alternative. The booking agent would have to return to the cabinets each time to retrieve the flight cards; since there were many booking agents who might want to retrieve the cards, the agents couldn't take more than one at a time. During busy schedule periods, this process could stretch out the booking process indefinitely.

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