Reservisor
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.
In an era where aircraft rarely flew with 75% of the seats filled, this system dramatically reduced the number of phone calls.
[2] Amman approached a number of business machine vendors about building the system he referred to as the Reservisor, but most proved uninterested.
Teleregister had started as part of Western Union, a division that sent stock market quotes across the country and presented them in "big board" form instead of a ticker.
Booking operators were equipped with terminals that looked like a smaller version of the control system, replacing the holes with lamps.
Encouraged by the Reservisor, but ultimately unhappy with the advantages it offered, Amman started examining a much more advanced system that handled not only the availability issues, but the actual seat inventory as well.
At about this time, Howard Aiken had started work with the highly publicized Harvard Mark III computer, which used a drum memory for storage.
American and Teleregister decided to make a drum-based system that allowed direct manipulation of the number of seats available.
Amman spent a considerable amount of time studying the user interaction with the machine, trying to find an easy way for the operator to query the data for a group of flights.
[1] The trials included buttons, dials, rolls of paper tape, loops of 35 mm film and finally, the "destination plate".
The plate consisted of a metal card with notches on the edge that engaged switches in the terminal, which energized lines back to the drum to retrieve information for all of the flights to that destination at once.
When a booking was made, a lever on the terminal subtracted one seat from the value stored on the drum, while another allowed it to be added back in the case of a cancellation.
In 1956 a new version was installed at American's New York West Side Terminal with storage for 2,000 flights 31 days into the future, and improved access times to about half a second.
Modified versions, larger or smaller, were also sold as the United Airlines' "UNISEL", New York Central Railroad's "Centronic", and a variety of warehousing and hotel room availability systems.
The Magnetronic Reservisor largely solved the booking and availability problems, but this left the issue of recording passenger information after the sale was made.
Working with IBM, Amman built the Reserwriter, which allowed operators to type passenger information onto a punched card for storage.
To add to the confusion, the full process of booking a flight, even a single-leg, required the input of 12 different people and took as long as 3 hours in total.
IBM was at that time starting work on the Semi-Automatic Ground Environment (SAGE) system for the United States Air Force, which had a large number of features in common with a booking system; remote communications with "offices", real-time updating, interactive user terminals, and storage of large amounts of information.
