Aegis radar case

The following is an excerpt from a letter written by the Admiral who was U.S. Chief of Naval Operations when the U.S.S. Vincennes shot down a civilian Iranian airliner over the Persian Gulf in July, 1988 despite using Aegis, the most advanced radar in the world.

.... Contrary to your assertion, Aegis works and it has been so proved. The system, since its introduction, has performed to its full capabilities. More testing has been done on Aegis than on any other system to date. ..... Other critics, meanwhile, lament that Aegis did not work because it didn't distinguish between the size of an Airbus and the size of an F-14. The fact of the matter is that Aegis is not designed to identify electronically radar contacts by size discrimination.

The Admiral viewed "the system" as the Aegis radar and says it performed as designed. But if we think of "the system" as the process of protecting both U.S. military activities and local civilian activities, the system failed, perhaps in part because Aegis could not differentiate between airliners and fighter planes, and in part because the user interface was inadequate for the task at hand:

.... The altitude information was not displayed on the main screens, but only on one of various subtables that had to be called up on a smaller screen. There was no indication of rate of change of altitude, not even a choice among ascending, cruising, or descending.

And this interface issue may have been only part of the problem the crew was facing when making a life or death decision for 290 people on the airliner:

.... The crew had been fatigued and stressed by frequent calls to general quarters battle stations. Each time the exhausted crew members went below decks to sleep, another small Iranian patrol boat was spotted carrying potential attackers, and, following combat procedures, again the crew members were called out of their bunks. ....Although the radar showed the commercial airliner climbing on a normal flight path, at least one fatigue-stressed CIC [Combat Information Center] operator anxiously and repeatedly told the captain that the 'target' was descending.

Questions:

1. Use the WCA framework to describe the system described here.

2. Explain how this example shows that different views of a particular system may lead to completely inconsistent conclusions about how well "the system" is operating.

Sources: Trost, C. A. H. "Aegis Has Performed to its Fullest." Letter to Editor, New York Times, Dec. 22, 1988;
Neumann, Peter. "Aegis, Vincennes, and the Iranian Airbus." ACM Sigsoft: Software Engineering Notes, Vol. 14, No. 5, July 1989, p. 20;
Moore-Ede, Martin. The Twenty-Four-Hour Society: Understanding Human Limits in a World that Never Stops. Reading, MA: Addison-Wesley Publishing Company, 1993, pp. 3-4.

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