Day 2 – Wednesday 18 September 2013
Session 5 - Technology
ABSTRACT
Paul Nef, Business Development Director, Asia-Pacific, Honeywell Aerospace
Human Factors Considerations in the Design of Modern Weather Radar and Operator
Training for Airborne Weather Radar
The challenge of in-flight weather avoidance is ever with us. Weather encounters, often
described as “inadvertent,” continue to occur and they vary from hail and intense rain
associated with thunderstorms - to icing due to penetration of top-of-storm - to turbulence
from both in-storm and near-to-storm encounters. The resulting aircraft damage and human
discomfort and injury costs remain one of the many concerns of aircraft operators
everywhere.
From the beginning, weather radar was recognized as a precipitation related turbulence
avoidance tool, whose utility depends on both the capabilities, and limitations, of the
weather radar itself and the skill of its operator. Radars have evolved through design from
tube powered equipment to the more recent solid state transmitter based equipment, both
of which use a variety of antennae technology implementations with the latest
implementations of transmission technologies mated to state-of-the-art microprocessor
powered, database enhanced systems, but the basic RF technology has remained much the
same. Display symbology, though having morphed over the years as technology changes,
has been a slow-changing feature of weather radar implementation, which one can argue
has both contributed to and detracted from better weather radar operations. In spite of the
technological innovations, however, weather radar is still dependent on detecting and
processing precipitation amount, size, composition and rate. Heavy precipitation still
attenuates the radar return, reducing the reliability of the displayed information. And, every
radar design has its associated design deficiencies and limitations.
On this basis, weather and weather radar knowledge and principles of operation, though
having evolved over time, remain mostly tied to the originals from which the first radars
derived their need and utility to aircraft operators:
• Typical storm profiles vary by geographic region across the globe
• Storm shape and intensity are both important to understand its potential dangers
• Pilots should seek to identify the weather relevant to the current flight/flight path
• Avoid the most intense echoes by at least 20 NM
• Deviate around the upwind side of a storm
• Never deviate under a storm
• Updrafts can carry moisture in to the freezing level where it poses a continuing
threat to transiting aircraft
Some years ago, studies revealed that a key factor in weather related aircraft upset
incidents is that crews failed to gain the necessary weather awareness in time to reroute or avoid a hazardous situation. In studying both weather radar design and
operator training issues, Honeywell human factors experts came to several conclusions
with implications for potential application to weather radar design and weather radar
operator training:
 Then current weather radar designs, including both RF technological implementation
and information display technologies can and must be improved
 Then current training practices revealed knowledge gaps in operator understanding
of radar fundamentals
 There is large variability in pilot’s use of radar both within and amongst airline
operations departments
 There was large variability in training standards across major airlines involved in the
studies
 Poor tilt management was revealed as a major factor in the number of incidents
recorded
 Poor training results in misinterpretations of radar returns
 Much of the then-current training programs relied heavily on on-the-job training
with junior pilots learning from senior pilots in flight
 Better training and retraining for operators is necessary to reduce the number of
unpleasant encounters with in-flight weather
 Technology implementations of more intuitive (user-centered) displays should be a
part of the improvement plan on which better operator training is based
The paper describes the results of Honeywell’s efforts to adapt radar technology
implementations and training therefor with the following goals:
 Improve broad-based operator understanding of weather radar fundamentals
 Improve weather (situational) awareness based on the assumption that pilots can be
effectively trained on human-factor based information display methodologies
 Improve weather avoidance decision-making
 Reduce operator workload
 Gain high pilot acceptability of the new designs and training methods