The reuse of some object-oriented code has caused tactical
headaches for Australia's armed forces. As virtual reality
simulators assume larger roles in helicopter combat training,
programmers have gone to great lengths to increase the
realism of their scenarios, including detailed landscapes and
- in the case of the Northern Territory's Operation Phoenix -
herds of kangaroos (since disturbed animals might well give
away helicopter's position).
The head of the Defense Science & Technology Organization's
Land Operations/Simulation division reportedly instructed
developers to model
the local marsupials' movements and reactions to
helicopters. Being efficient programmers, they just
re-appropriated some code originally used to model infantry
detachment reactions under the same stimuli, changed the
mapped icon from a soldier to a kangaroo, and increased the
figures' speed of movement.
Eager to demonstrate their flying skills for some visiting
American pilots, the hotshot Aussies "buzzed" the virtual
kangaroos in low flight during a simulation. The kangaroos
scattered, as predicted, and the visiting Americans nodded
appreciatively . . . then did a double-take as the kangaroos
reappeared from behind a hill and launched a barrage of
Stinger
missiles at the hapless helicopter. (Apparently the
programmers had forgotten to remove that part of the infantry
coding.)
The lesson?
Objects are defined with certain attributes, and any new
object defined in terms of an old one inherits all the
attributes. The embarrassed programmers had learned to be
careful when reusing object-oriented code, and the Yanks left
with a newfound respect for Australian wildlife.
Simulator supervisors report that pilots from that point
onward have strictly avoided kangaroos, just as they were
meant to.
-- From June 15, 1999 Defense Science and Technology
Organization Lecture Series, Melbourne, Australia, and staff
reports
