NASA flight controllers face data overload
- By Florence Olsen
- Jun 16, 1997
The memo, written by a NASA flight controller, complained there is "so much to
play with that adjusting the stuff on the console distracts from keeping up with
Also, flight controllers rely too much on the automated telemetry functions, the memo
said. On one simulated flight, controllers discovered the telemetry had malfunctioned
after it was too late to regain control.
Such design problems in mission-critical decision-support systems trouble not only NASA
controllers but also military command-and-control officers, air traffic personnel and
others whose jobs are critical for safety.
David Woods, an Ohio State University professor who advises government agencies on
decision-support systems, said too much complexity is canceling out the benefits of
flexibility. Woods is co-director of OSU's Cognitive Systems Engineering Laboratory.
His work with high-profile agencies has shown that automation-contrary to
expectation-tends to increase the human workload in a crisis and reduce the operator's
awareness of what needs attention.
Problems with decision-support systems also have perplexed the Task Force XXI staff of
the Army Training and Doctrine Command, which runs the Army's battlefield digitization
program [GCN, June 2, Page 1].
Some NASA flight controllers have tackled the information overload head-on by
requesting mask displays that hide some of the windows they must keep open on their
Instead of trying to keep up with separate detail screens, overview screens and layers
of intermediate screens, they want high-level screens that display warning signals when
triggered by lower-level events.
"It's a learning process" for NASA, said Steven Gonzalez, delivery manager
for the Systems Development and Operations Division of NASA's Missions Operations
Directorate. The agency first has to understand the systems better to be able to put in
the required automation, he said.
But even if the extreme flexibility of new workstation systems has created a new set of
problems, hardly anyone at NASA would want to return to the previous fixed,
black-and-white character displays.
Those static displays have given way to Sammi, a dynamic data visualization tool from
Software-Intercomp Inc. of Houston. Flight controllers use Sammi to customize their
displays to their own preferences. The only limit on flexibility is a freeze on software
display changes, 30 days before a mission.
NASA has moved all but two flight-control functions from the center's IBM Corp. Model
9291-490 mainframe and onto 275-MHz Digital Equipment Corp. 3000-900 Alpha AXP servers
linked to Digital 3000 workstations by a Fiber Distributed Data Interface network.
IBM RS/6000 front-end processors feed flight data directly to the Alpha servers and
workstations. Still on the IBM host are command and trajectory functions. Command
functions make the transition to the workstation environment in 1998. Trajectory control
will be the last to go.