2003 IMTA Proceedings - International Military Testing Association

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result is that OZ shifts the workload requirements for flight from one of visual scanning of
separate instruments and displays, requiring intensive integration and computation, to nearly
instantaneous or ‘direct’ perception of an integrated picture. This allows a glance at OZ to
convey most of the information contained in an entire panel of conventional instruments that
may take several seconds to scan. Although OZ presents the pilot with processed data, the
processing does not obscure information nor does it make covert, de facto decisions for the
operator.
Experiments
Two experiments are reported. Experiment 1 evaluated the overall OZ approach, the
general scaling of flight parameters to OZ symbology, and the software implementation.
Experiment 2 involved the tasks of simultaneously flying with instruments and reading. We
considered this a particularly compelling demonstration since it is a task that can be clearly
important operationally but is patently impossible with conventional flight instruments, but with
OZ, it’s easy.
Experiment 1: The Demonstration of the OZ Concept
This was the first formal evaluation of OZ; the goal was to ensure that OZ was scaled
such that flight performance with OZ under simple conditions was comparable with that obtained
with conventional instruments.
Method
Participants: Two first year medical-students with no previous pilot experience
volunteered for these studies conducted over a two-month period. Neither participant required a
refractive correction and both were less than twenty five years of age.
Simulator and Equipment: Elite (Prop. Version 4) simulator software running on a
Macintosh computer provided the Cessna 172 aerodynamic model and the conventional
instrument display (CD) used in this and the following study. The manufacturer modified the
commercial software to export flight data. The OZ display was created with custom C++ code
running on a Pentium PC receiving the exported simulator data. Both OZ and the CD were
presented on 19-inch monitors placed adjacent to each other. An opaque screen blocked one or
the other monitor from view depending on which display the participant was flying. The flight
controls were the same for both displays. Aileron, elevator, and engine controls were input with
a Precision Flight Control Console, Jack Birch Edition. Rudder control was disabled.
Task: Participants were to fly straight and level on a course heading due south at 3000
feet at a constant indicated air speed of 100 knots for about three minutes per trial. Participants
could rest between trials. Completing a condition required between one to two hours per
participant.
Independent Variables: In a two factor experiment, two levels of flight display (OZ and
the CD) were compared for the 4 levels of the default turbulence that the Elite Simulator
provided (none, low, moderate, and severe).
Training: The participants had no formal experience with either CD or OZ before the
experiment. The task of flying straight and level was described and illustrated to the participants
with both displays. Participants were given instructions about the instruments, and all questions
were answered about the displays until the participants said they were satisfied that they
understood the task. Data collection started with their first flight.
45 th Annual Conference of the International Military Testing Association
Pensacola, Florida, 3-6 November 2003