Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter.
Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 217
6
Navigation and Piloting Technology
SUMMARY
A broad range of vessel- and shore-based technologies are emerging that
have considerable potential for improving navigation safety. The effective applica-
tion of high technology in operations and professional development programs
offers a substantial means to significantly reduce risk in the near term. Interna-
tional technical and performance standards and criteria, and corresponding na-
tional standards and criteria are needed to guide the systematic introduction of
new navigation technologies with capabilities and configurations that are well
designed to enhance navigation safety. Technology is an important component of
an overall approach for solving safety issues confronting marine transportation.
To achieve the full potential of advanced technology for improving safety, sys-
temic factors will need to be comprehensively addressed including ( 1 ) operator
qualifications and training, (2) manning, (3) pilotage, (4) systems maintenance, (5)
regional variations in port and waterway operating environments, (6) economics,
and (7) institutional policies.
Successful application and effective use of new and innovative technolo-
gies require validation of the technologies, changes in operational procedures,
and operator training. These efforts are necessary not only to ensure suitability
and reliability of complex and integrated systems but also to demonstrate the
practical value of these systems to mariners. Validation methods for navigation
technologies that rely on software are not fully developed; there are few proven
methodologies that offset the need for extensive field trials in the full range of
operating conditions in which these technologies will be applied. Reliability as
217
OCR for page 218
OCR for page 221
OCR for page 222
OCR for page 223
OCR for page 224
OCR for page 225
OCR for page 226
OCR for page 227
OCR for page 260
OCR for page 261
OCR for page 262
OCR for page 263
OCR for page 264
OCR for page 265
OCR for page 266
OCR for page 267
OCR for page 268
OCR for page 269
OCR for page 270
Representative terms from entire chapter:
piloting technology
218
MINDING THE HELM
sessment techniques using statistical models are not mature for determining sys-
tem faults in software-dependent systems. Further, although the capability to
tailor visual presentations of navigation data can be a powerful tool, it also has
the potential to increase risl<. For example, important navigation information
could be screened out of the display if system designers or users lacl
NAVIGATING AND PILOTING TECHNOLOGY
219
vironmental risl
OCR for page 220
220
TABLE 6-1 Summary of Technology Improvement Options
MINDING THE HELM
Category/
Option
Immediate Near-term Long-term
Action Action Action
PASSAGE PLANNING
· Develop international standards for
electronic charts
Develop international standards for
electronic chart systems
Develop international standards for
automated chart corrections
Require electronic charting systems to
meet international standards
Provide electronic chart data bases by
or through national hydrographic offices
Conduct more timely and complete
hydrographic surveys
Develop automated systems for chart
corrections
Provide accurate, timely reports on
environmental conditions
Expand real-time environmental
information systems
POSITION FIXING
.
.
.
.
x
x
Develop minimum international
standards for Electronic Chart and
Display Information Systems (ECDIS)
Indemnify from liability providers of
electronic charts and manufacturers ot:^
electronic chart systems
Review and if necessary revise laws x
and regulations for bridge team operations
Retain paper charts as a backup for ECDIS
Improve accuracy of short range aids
to navigation
Improve positioning of buoys and fixed aids
Expand distribution of racons and
high-intensity lighted ranges
Develop and install electronic ranges
for poor visibility conditions
Accelerate implementation of GPS and DGPS
Accelerate development of electronic charts
Accelerate schedule for harbor surveys
Increase attention to human factors
aspects of ECDIS
Develop long-range plans for improving
aids to navigation
Review long-range plans for production
of charts
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
NAVIGATING AND PILOTING TECHNOLOGY
TABLE 6-1 (Continued)
221
Category/
Option
Immediate Near-term Long-term
Action Action Action
COMMUNICATIONS
· Aggressively enforce VHF radio
regulations
· Improve Vessel Traffic Service (VTS)
communications procedures to reduce
potential for human error
Implement more efficient data
communication in VTS-user interactions
Improve radio circuit discipline,
including institution of standardized
vocabulary
Create additional VHF channels for
commercial users
Improve radio bandwidth efficiency
.
.
COLLISION AVOIDANCE AND SURVEILLANCE
· Develop new Automatic Radar Plotting
Aid (ARPA) functions and display
.
.
capabilities
Review, revise international ARPA
standards to permit use of alternative
technologies for speed measurement
Standardize data outputs from
integrated systems
Adapt low-light video and sound
discrimination systems for marine use
Increase use of advanced technologies
such as automated dependent
surveillance (ADS) in VTS operations
where feasible
Conduct comprehensive analysis of
requirements for ADS data
communications
· Accelerate research of efficient data
communications systems
STEERING AND TRACK KEEPING
· Improve autopilot algorithms for
shallow-water maneuvering
· Allow use of high-performance
autopilots in pilotage waters
Establish legal equivalency of ECDIS
for plotting
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
continued on next page
222
TABLE 6-1 (Continued)
MINDING THE HELM
Category/
Option
Immediate Near-term Long-term
Action Action Action
.
BRIDGE TEAM MANAGEMENT AND
DECISION MAKING
· Accelerate use of integrated
navigation systems
Develop more complete standards for
NEMA 0183
Develop standards for interfacing
bridge equipment, engineering systems,
and cargo/ballast systems
Develop international standards for
alarms, displays, and controls used in
Integrated Ship Control Systems (ISCS)
Develop rules for bridge configuration
of ISCS
Redefine automated dependent
surveillance (ADS) to develop a
performance-based standard
Conduct research and development to
improve ADS to simplify integration
and reduce cost
Encourage development of portable
communications and navigation systems
(PCNS)
· Develop piloting expert systems to
support integrated bridge systems
(IBS) and integrated ship control
systems (ISCS)
Develop expert systems for complex,
busy waterways
Conduct research and development to
improve compatibility of expert
systems with PCNS, IBS, and ISCS
Dedicated radio frequencies for marine
electronic data transmission
Develop efficient and standard data
protocols
· Develop international standard for ADS
Conduct risk assessments of integrated
bridge operations and equipment
Develop regulations allowing non
traditional bridge team
Review and amend manning
laws and regulations
.
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
NAVIGATING AND PILOTING TECHNOLOGY
TABLE 6-1 (Continued)
Category/
Option
Immediate Near-term Long-term
Action Action Action
WEATHER AND ENVIRONMENTAL
MONITORING
· Transmit PORTS data electronically for
use with ECDIS
Improve hull stress sensors and
methods for mounting them
· Extend PORTS system to provide service
to all major U.S. harbors
DOCKING EVOLUTIONS
· Conduct research and development to
hasten implementation of automated
docking systems
· Develop more-reliable winch-control systems
x
x
x
x
x
IMPROVING NAVIGATION TECHNOLOGIES
A wide range of technological options for enhancing maritime safety was
examined during the study. The analysis presented here is organized by naviga-
tion and piloting function. Within each functional classification, the current state
of practice is outlined, and options are identified for immediate action, incre-
mental improvement, and long-term development of technologies. For purposes
of clarity, the options are italicized in the text.
Immediate-action items are those needed to guide the application of emerg-
ing technologies. They deal principally with technical and performance objec-
tives and standards. Incremental improvements were defined as those already
under way or achievable in one to three years. Long-term development alterna-
tives were those only now being proposed, those having an uncertain time hori-
zon, or those requiring extensive international coordination or change to imple-
ment. Such strategies would be slow to produce effects but would have the
benefit of ensuring that the diverse elements of the maritime community worked
together and had time to accept any changes.
The functional classifications include:
passage/route planning;
. . i. .
poslhon ilxlng;
communications;
collision avoidance and surveillance;
steering and track keeping;
bridge team management and decision making;
223
224
MINDING THE HELM
weather and environment monitoring; and
· docking evolutions.
The analysis assumes some basic knowledge about each technology. This
background is provided in Appendix I, which defines each technology men-
tioned in this chapter and describes the traditional bridge setup, including place-
ment of technologies. Several important off-ship technologies, including VTS
systems and marine simulations used for waterway design and pilot training, are
addressed in detail in Chapters 1, 3, and 5 and Appendix E.
Passage/Route Planning
Mariners plot their intended track line on a paper nautical chart showing
waypoints for course and speed changes. The technologies used include tradi-
tional nautical charts; navigation publications such as the Light List; and where
available, electronic charting systems.
Various technical and institutional factors constrain the full application of
electronic charting technology. These include the lack of international perfor-
mance standards (although these are under development), the unavailability of
government-provided electronic charts or chart data, and the fact that the hydro-
graphic data that are available for many pilotage waters are not as accurate as is
the capability to determine precise positions using differential GPS (DGPS) and
electronic charting systems. Further, the process of accumulating electronic data
bases is slow and costly.
Choosing the Charting Medium
The choice of paper or electronic chart may be based on the relative advan-
tages of the presentation format or the ease of use. (Paper and electronic charts
also differ in legal status, an issue discussed later in this chapter.) Paper charts
permit the user to see wide areas in sufficient detail to assist with voyage and
route planning, and they can be folded and moved about the bridge to aid in
visual orientation and identification of geographic features and aids to naviga-
tion. They also remain available for use if an electronic charting system fails to
operate correctly or becomes disabled.
Whether all features of paper charts can be replaced by electronic charts has
not been established (Gold, 1990a). Electronic charts, while capable of provid-
ing the same or greater detail as paper charts over wide areas, must either con-
dense this information into a smaller display or present only sections of charts
(scaling factors as they affect accuracy are discussed later in this section). On the
other hand, precise navigation data and radar images can be integrated into an
electronic presentation to provide real-time steering guidance and hazard-avoid-
ance features. Additionally, software-driven, computer-aided features can be de
NAVIGATING AND PILOTING TECHNOLOGY
225
signed to aid in data analysis and decision making. For example, color coding
could be generated to mark depth contours. The master, pilot, or watch officer
can determine what hydrographic data are displayed to aid in their transit. Criti-
cal information needs vary from situation to situation. It is probably not neces-
sary to display all information at all times. In fact, the most effective use of
electronic chart display features appears to be selective display of information.
However, an incomplete understanding of information needs for a transit or
errors made in selecting what data are displayed could result in failure to display
all key information needed at various locations along the vessel's route. What to
display and when to display it are basic issues in determining whether Electronic
Chart Display and Information Systems (ECDIS) can replace existing traditional
equipment such as a separate radar console and paper charts. Empirical research
is currently under way to assess which information in an ECDIS is most used,
and which is most useful to the mariner (Smith, 1993~.
These factors could complicate establishing use of electronic charts as legal-
ly acceptable replacements for paper charts for planning and conducting naviga-
tion. Performance criteria would need to address minimum display requirements
for hydrographic data and ship parameters such as depth, breadth, and maneu-
vering characteristics. In any case, it would be important for the mariner to be
aware of which data will be displayed automatically and to what extent this data
can be controlled by the user.
Scaling Factors
The scale of electronic chart displays needs to be constrained to ensure that
chart data are not depicted at larger-than-intended scales, because the level of
charted detail and the accuracy change with the scale of the chart. In general, the
larger the scale and the smaller the area display, the more accurate the feature
based on field survey standards and the precision with which data can be pre-
sented. The standards for the horizontal accuracy of paper charts are based on
the scale of the original field survey. Normally, the error budget for a chart is 0.8
mm at the scale of the survey. For a 1 :50,000-scale chart, features and soundings
are thus required to be accurate to 40 m; for a 1:10,000-scale chart, 8 m. The
scaling constraint undoubtedly will lead to demands for new, large-scale, highly
accurate hydrographic surveys, especially of harbors and harbor approaches
(Donald Florwick, NOAA, personal communication, October 30, 19923. It also
may be useful to have software switches that change the level of detail to corre-
spond to the scale presented on the electronic-chart visual display. Further, the
hydrographic data need to be very accurate and reliable so that the mariner is not
given a false sense of security, because the appearance of the high-technology
display may be better than the data presented.
Thus, even as electronic charting systems can offer unique additional sup-
port for navigation functions other than voyage planning, they also have the
226
MINDING THE HELM
potential to induce error through data screening features. Therefore, the federal
agencies involved in development of standards for electronic charting systems
are supporting the ECDIS concept. Only electronic charting systems that meet
international performance standards including some minimal level of detail
would carry the ECDIS designation and be considered to meet legal carriage
requirements.
Accuracy of Nautical Charts
An electronic charting system, when combined with real-time position data
conveys a convincing sense of reality. The visual presentation can be easily
related to the maneuvering situation, facilitating the interpretation and applica-
tion of displayed information. This capability appears to cause users familiar
with system operation to believe the video display and to become increasingly
reliant on it. Therefore, the information displayed needs to be as accurate as
possible.
Although electronic charting systems offer real-time utilization and increased
precision in position fixing, and rapid update capability, the available hydro-
graphic data upon which these features rely are incomplete (Box 6-11. Thus, the
hydrographic data bases for electronic charts will not be any more reliable (in
general) than those for paper charts in the near-term, because the same survey
data are used. Because the accuracy of the available data is generally less than
the precision by which the data can be displayed by an electronic charting sys-
tem, mariners must consider the limitations of the data when using these sys-
tems.
Another accuracy factor is that NOAA has a substantial backlog of reported
chart discrepancies that have yet to be resolved. The agency is capable of con-
ducting field investigations of only about 20 percent of reported discrepancies
each year. NOAA, which produces 1,000 different nautical charts, had almost
2,000 request for new surveys as of August 1993, some dating back to 1984, and
400 to 500 new wrecks and obstructions are reported annually for the East and
Gulf coasts alone (NRC, 1994~.
NOAA plans to make users aware of the limitations of nautical paper charts
by adding source diagrams, which will show the date, source, and scale of the
survey data (Prahl, 1992~. Knowledge of chart shortcomings will help users
make informed decisions. But even greater demands will be placed on hydrogra-
phers by the nature of electronic displays. The development of digital hydro-
graphic data bases is the most labor-intensive and costly step in making electron-
ic charts available to the mariner. The International Maritime Organization's
(IMO) ECDIS Provisional Performance Standards require that data bases be
supplied by a national hydrographic office. However, electronic chart data bases
must be developed on an international scale to provide complete coverage and
<~ ~ ~ = ~227
I i! 1llllllllllIllil~l~llllIIlilIlIlllTITITTTTTTTTT~l~lllT 111 lIll~llllll~ll!lTll TT .
i66.:cI1l~llA~.iph, 4:~vel Instill
s~s~s~s~s~s~s~s:s~s~s~sss:.s.ss~ss.s.ss~ss.s.s.s ss~ss.s.ss~ss.s ..s~sS.ssssss~ss.sss.ss~ss.s.sss~ss~s~s~s~ssssss.sssssssssS~s~sss~sssssssssssssss~s~s~sssssssssssssssss~s~s~sssss~s, ,.ssssssss~sssssssss ~,ssS~sssssssssss~sssss~s~sssss~s~ssss
I
-~#l~=l~I~
Bulls
- ~
it!!! 1
updated rogul~ly, and 1berc needs to be consistency iD units of measure) the
process involves digidzing paper abbots and, idcaUy, conducing new bydro-
graphic surveys using state-oPtbe-=t technology to provide 100 percent bottom
coverage in SigDi5C8Dt gems. The data flats Id procedures to produce the
data bases are in place,2 but digitizing paper charts of U.S. maters alone is ex
1Present NOAA cabs ma use Bee Elbows, or millers Conversion lo 1be metric system, now
under may, is expected lo lie lO lo 13 yearn Thus, it is possible for a vessels echo sounders Ode
gables, Ed nautical cabs lo be in Wee di~renl Unix. Electronic cuing systems need lo be
camp of convening between ~1 these menses Ed displaying constant units.
2Tbere He Lao methods of digitizing dale. To produce raffler digLa1 dam, Me pier cab is passed
Tough ~ scanner, whim captures ~ digital image. The raffler image can be displayed on a consular
monitor but ilS Velures cannot be deleted or manipuIaled individually. An overlay for user input and
cb=1 updates can be added. Vector dale, on 1bc oar hand, ~ produced by storing position and
Bud on iron far each arc on 1hc char. Vector iron is more discuss Fan raster
data to gather but oars 1hc bencA1 of scleclivc manipulation and display. Vector data is required far
ECDIS. Elec~oMc cog ~spl~ can use either type of dam.
260
MINDING THE [IELM
though the PORTS system has been very well received by its marine users,
NOAA reports that agency resources are not available for long-term operation,
much less for expansion of the capability to other ports. The agency has suggest-
ed that revenues collected from the marine transportation industry and main-
tained in the Harbor Maintenance Trust Fund (in excess of funds needed for
channel maintenance) might be an appropriate source of funding for continua-
tion and expansion of the PORTS program.
Docking Evolutions
Docking large vessels is a time-consuming and potentially hazardous opera-
tion. The velocity and position of the ship as it approaches the dock must be
controlled carefully to prevent damage to the dock or the ship. This maneuvering
requires skill and experience; control of the ship's engine, rudder, and bow thrust-
er (if available) must be coordinated accurately with the forces provided by one
or more tug boats to achieve proper velocities in an environment of wind and
currents.
Little research and development has been conducted in recent years related
to docking technology, although two types of technologies have been introduced:
dual-axis docking Doppler systems and constant tension winches. Constant ten-
sion winches are very useful during docking evolutions. They are designed to
maintain constant tension on the wire ropes used to winch or hold a ship along-
side a pier. The tension can be set to avoid the parting of these ropes that would
endanger linehandlers on the ship and the pier and that would complicate dock-
ing. This feature also allows the ship to be warped along the pier to attain the
desired position.
Tests are being conducted with automated docking systems. Real-time pre-
cision navigation systems also can be employed in such systems. For example,
installation of DGPS antennas on both the bow and stern could be used to pre-
cisely monitor both the forward and lateral movement of the vessel during dock-
ing maneuvers.
Options for Incremental Improvements
Automated docking systems are a promising new technology. Ongoing re-
search and development could be accelerated to allow early implementation of
automated docking systems, which could be helpful in certain U.S. ports. Ade-
quate control and positioning technology is available, but additional research
and development is needed to produce autonomous systems. Such systems are
under development in a number of countries as part of "intelligent ship" pro-
grams. The most notable advances have been made by the Japanese, who in 1990
conducted an evaluation of their automatic berthing and unberthing system
NAVIGATING AND PILOTING TECHNOLOGY
261
aboard the experimental ship Shoji Maru.14 Experiments with the Japanese sys-
tem showed that smooth and accurate transitions to and from berth were possi-
ble, that the orders generated by the system mimicked those expected from an
experienced captain and docking master, and that the approaching speed of the
ship was reasonable and safe. Although autonomous systems have yet to be
deployed, a number of experimental docking-assist systems are undergoing eval-
uation aboard operating vessels.
Winches require heavy maintenance because of the harsh environment of
the weather decks on which they are located. It might be useful to develop more-
reliable and less-maintenance-intensive winch-control systems to ensure their
availability for use during docking evolutions.
Options for Long-Term Development
No specific options for long-term development were identified.
TECHNOLOGICAL CHANGE
How Marine Navigation Technology is Adopted
Historically, advances in marine navigation technology have been driven
largely by military needs and considerations (such as radar in World War II), and
to some degree, by marine-related missions of federal agencies (e.g., the aids to
navigation maintained by the Coast Guard). Now, however, certain advanced
navigation equipment can be applied as an integral part of bridge design to gain
an economic benefit. Advances in electronics and space technology permit auto-
mation and integration of navigation tasks such as fixing and displaying the
ship's position. Automation facilitates reduction in manning, a change in prac-
tice pursued by the shipping industry to reduce operating costs; automation also
can be applied to expedite the work of the remaining crew, a useful feature on
complicated modern ships. The trend is for ships to become more automated
overall (NRC, 1990a).l5
Change generally has evolved slowly in the marine industry, in part because
most technology has not been developed or regulated centrally. However, eco-
nomic competition has increased the pace of technological change. History shows
14The Japanese Intelligent Ship Project is a joint research program organized and managed by
seven shipbuilding companies under the Shipbuilding Research Association of Japan. The ship is
owned by Tokyo University of Mercantile Marine.
15Technology exists for remote and centralized monitoring and control of the engine room; water
and fuel flows; and such functions as navigation, loading and unloading, distribution of ballast for
stability, maintenance, inventory of parts and stores, and even administration (Ohmes and Robinson,
1987).
262
MINDING THE HELM
that shipping companies adopt new technologies if their actual use substantially
reduces operational risk and uncertainty (and thereby economic risk). The speed
of adoption depends on availability and reliability of the technology, its proven
value through demonstrated effective application, and its cost. Another factor
affecting application is that use of advanced technologies involves a complex of
changes related to design, performance, and reliability, some of which may in-
creaserisks(Aranow, 1984;NRC, 1991b;Reason, 19923.0therimportantfac-
tors affecting technology acceptance and application are impediments to innova-
tion and application of technology embodied in laws, regulations, and legal
precedents.
Two examples of adopted technologies, albeit motivated by official man-
dates, are bridge-to-bridge communications and radar. Marine pilots now con-
sider VHF radio and radar fundamental to piloting practice and have been instru-
mental in establishing their near-universal application. This is a legal as well as a
practical choice. If a pilot fails to use available proven equipment and an acci-
dent occurs, then a defense of prudent seamanship becomes vincible in disciplin-
ary proceedings. This concern may be applicable to newer technologies if their
use becomes "fundamental" to basic navigation practices.
Marine Transportation Companies and Technological Change
The key force driving the installation and use of navigation technology by
marine transportation companies is economics, although the economic contribu-
tion of safety improvements and public interests in safety may in some cases be
strongly considered in decision making. If the economic benefits of a technology
are not obvious-and they may not be then vessel owners are not inclined to
buy it without an official mandate that provides incentives or requirements to do
so. The economic influence in a highly competitive industry is so powerful that
it could work against a safety scheme based on universal voluntary application
of specific technologies. Increases in operating costs (including any associated
with mandated technology) that affect financial well-being could lead to a shake-
out in ship routing, fleet composition, or both. This result would determine
whether there would be a net benefit in economics or safety. Nevertheless, a
small but growing number of operating companies have made considerable in-
vestments in high-technology integrated navigation systems, for example, to fa-
cilitate uninterrupted passenger service or to reduce operational (and economic)
risk in tanker or freight operations (Herberger et al., 1991~.
Mariners and Technological Change
Dependent as it is on evolving economic, safety, and legal pressures; tech-
nology acceptance can be an arduous, piecemeal process. Mariners are often
ambivalent about change, and they tend to cling to proven traditional methods
NAVIGATING AND PILOTING TECHNOLOGY
263
until convinced that a new technology works. As an illustration, testimony solic-
ited from marine pilots indicates that their work remains more an art than a
science. Some feel that "more sophisticated technologies do not contribute much,
and may only serve to increase the load on the pilot" (Ramaswamy and Grabows-
ki, 19921. Yet many pilots have become ardent advocates of technologies such as
radar, and especially over the last several years the use of marine simulation for
continuing professional development. Likewise, if emerging high-technology
navigation systems can be demonstrated to be significantly helpful in their work,
marine pilots are likely to become ardent supporters of universal use of such
technologies. That is, they will unless operating companies attempt to substitute
advanced technology for pilotage services, thereby reducing pilotage costs and
threatening pilot livelihood.
Although some marine pilots have promoted the use of advanced navigation
technology, for example, the use of bridge-to-bridge radiotelephone (USCG,
1972), pilots in the past infrequently were brought in at the "proof of concept"
stage of technology development, with the notable exceptions of computer-based
marine simulation for channel design, and more recently, in developing some
VTS systems (Maio et al., 1991; NRC, 1992aJ. Perhaps pilots were not called on
more for the development of navigation technologies, because visual piloting is
still relied on to a significant extent in confined waters. But public expectations
for the safety of vessel operations are changing, and there are unmet needs for
all-weather, precision positioning capabilities. However, marine pilot expert
knowledge of shiphandling and confined water operations is a resource that could
be better used in the research and development of advanced systems, to help
ensure that these systems will achieve their full potential in reducing risk in
pilotage waters. Further, marine pilots are in a unique position to assist in vali-
dating newly introduced technologies and to provide leadership in their applica-
tion (such as for pilot-operated VTS or VTS-like systems).
What is occurring in marine transportation, then, is a convergence of old and
new navigation practices. The traditional and trusted piloting methods, which
rely heavily on visual observation (of varying acuity), use of radio and radar, and
the application of expert local knowledge, are being weighed against high-tech-
nology solutions that offer real-time information and support for precision navi-
gation and decision making but that have yet to inspire confidence and trust.
This quandary contrasts with the situation in aviation, where new systems
are tested by central authorities, and U.S. industry routinely complies with the
mandated schedule for installing and retrofitting the devices on all aircraft (Gold,
1990a). ICAO16 has broad powers to promulgate standards and practices for new
16The ICAO is more active and more adequately funded than the IMO, which is funded in accor-
dance with the respective tonnages of flag states. The IMO funding scheme is a problem because
over 20 percent of the world's tonnage is registered in Liberia and Panama; neither nation has
contributed to IMO activities in recent years due to internal financial difficulties in each country
(CHA, 1990).
264
MINDING THE HELM
systems. The development and implementation process is said by some to unfold
relatively quickly, although this depends on the point of comparison. What is
more, considering the total capital and operating costs of aircraft, measures which
enhance safety and performance were routinely considered as cost-effective
(Gold, 1990a). This receptiveness appears to have changed somewhat as a result
of less favorable economic conditions in the aviation industry. Nevertheless, the
well-established strong organizational structure and institutional processes that
facilitate the introduction of technology remain in place.
The acceptance by U.S. airlines of the Microwave Landing System (NILS)
provides a cogent example of more recent conditions. MLS was developed and
shepherded through ICAO by the United States as the landing system for the
next century. However, with the advent of satellite navigation, the airlines have
convinced the Federal Aviation Administration to establish a vigorous develop-
ment program to determine the feasibility of DGPS application to precision ap-
proaches, including Category III approaches (zero ceiling limitation). This user
initiative is based on economic benefits, where airlines believe that the flexibili-
ty of satellite navigation, with respect to coverage at all airports worldwide, user
preferred routes, single system for all phases of navigation, and application to
automatic dependent surveillance, will lead to substantial costs savings in their
operations (RTCA, 1992~.
Pitfalls of the Application Process: Some Examples
The introduction of new navigation technologies has been met more by
operator reluctance to give up traditional systems than by forward-looking en-
thusiasm. The absence of wholehearted support has created a number of prob-
lems concerning advanced technologies, including lack of standardized equip-
ment, a shortage of validation methodologies, regulatory standards that constrain
either optimal usage of technology or its further development (or both), require-
ments for specialized training, and considerable reliance on traditional practices
even when using advanced systems. Following are specific examples.
Multiple Equipment Configurations and Regulatory Restrictions
Two problems multiple configurations and regulatory restrictions are il-
lustrated by ARPA. Marine pilots responding to a committee inquiry complained
about the lack of standardized ARPA consoles, a frequent cause of pilot difficul-
ty in using this equipment effectively (Ramaswamy and Grabowski, 19921. Such
difficulty poses a safety risk if bridge team support to the pilot in making effec-
tive use of ARPA is inadequate, perhaps even canceling out the collision-avoid-
ance safety benefit ARPA is supposed to provide (Ramaswamy and Grabowski,
1992; Zabrocky, 1992~. Further, ARPA's capabilities are specified-and limit
ed by regulations (33 CFR 164.383. ARPA's plane of reference must be the
NAVIGATING AND PILOTING TECHNOLOGY
265
water plane; that is, speed data should be obtained through the water signal. But
water-speed instruments-once the only technologies available for determining
speed are neither very accurate nor very reliable. Today, navigation equipment
using DGPS signals can measure speed very accurately over ground. This data
cannot be used with ARPA, however, because regulations do not provide for
measurements by means other than water speed instruments. The result is that
mariners, frequently unable to obtain an adequate water signal, often enter speed
information manually, sometimes forgetting to change it later. Resulting ARPA
solutions are degraded in relation to the error introduced, increasing operational
risk.
Regulations addressing technology application can either foster or impede
research and development, depending on how they are written. For example, a
12-channel GPS receiver is required by the Coast Guard for the ADS/VTS sys-
tem for tank vessels over 20,000 deadweight tons in Prince William Sound (33
CFR 161.376~. As written, the regulation does not provide adaptive flexibility or
include provisions or incentives to motivate further improvements in positioning
accuracy or system integrity. But if the wording were changed to specify a min-
imum integrity comparable with that provided by the 12-channel GPS receiver,
the regulation still would result In the near-term adoption of this equipment
while also providing latitude for subsequent technological innovation.
Pe jormance Objectives and Assessments
Another concern is that construction and performance standards are not
available to guide the introduction of high-technology systems or to minimize
the unconstrained proliferation of different configurations and features. Advanced
technologies are becoming more reliant on software and therefore can be modi-
fied very rapidly much more rapidly than can traditional hardware-based tech-
nologies-for the purposes of correcting deficiencies and improving capabilities
(Buxton and Hornsby, 19921. However, the range of possible permutations and
the speed at which they can be made and introduced has the potential to exacer-
bate the difficulty that mariners, especially pilots, have in building and maintain-
ing familiarity with high-technology navigation systems. These difficulties are
compounded, because only a few standardized methods have been developed for
validating software short of extensive field trials. Validation is a current research
topic in the software engineering community and vessel classification societies
(Buxton and Hornsby, 1992; MacIennan and Shaw, 1992; Singpurwalla and Wil-
son, 19931. Such tests are the principal method for determining logic or pro-
gramming flaws in software and evaluating actual system performance relative
to designed capabilities. For example, before new or updated personal computer
software is introduced for sale, in addition to bench tests, special field trials,
referred to as "beta" tests, are conducted by individuals selected to challenge
266
MINDING THE HELM
software capabilities and performance. Many, but not necessarily all, "bugs" in
the software are identified for subsequent correction.
Generally, software can be tested without creating any physical danger.
However, this is not the case for field testing either software or hardware in
marine systems. It is difficult if not impossible to stress a technology sufficiently
to see if it works, in either a port-and-waterways operating environment or river
system, without exposing the vessel serving as the testbed to some physical
dangers. These dangers become more pronounced as the pilotage waters or traf-
fic situation become more challenging.
For most potential applications, it does not appear economically feasible to
employ large vessels in commercial service as dedicated testbeds, although some
limited trials may be feasible. Further, operational risk in conducting such tests
might be significant. Although small, maneuverable vessels could be employed
as testbed platforms for beta-like tests, even this is costly, not entirely without
risks, and it appears to the committee, not frequently done. Whether or how well
the results of such testing would transfer to larger platforms of far different
design, outfitting, and manning has not been ascertained.
Simulation technology has been used in a few cases to evaluate a new tech-
nology (Grabowski and Wallace, 1993; Schuffel et al., 1989) or to test technolo-
gy utilization (Akerstrom-Hoffman et al., 1993; Alexander and Klingler, 1992;
Gonin et al., 1993; Smith, 19931. Simulation offers a controlled environment
absent of physical dangers to the participants, and the ability to test the technol-
ogy under operating conditions too dangerous for field tests. Although far less
costly than field tests for the same level of empirical observation, the cost and
time-intensive nature of simulation, and the need to install and effectively inte-
grate the technology into the simulation, have impeded widespread adoption of
this technology for this purpose.
Another testing approach is to combine use of marine simulation and afloat
testbeds. This is the approach employed in the U.S. ECDIS Testbed Project, a
multifaceted government-industry demonstration, test, and evaluation project.
The project is supporting the development of international performance stan-
dards for ECDIS by the IMO. The U.S. researchers are testing the capability and
limitations of prototype ECDIS systems; evaluating the adequacy of proposed
international ECDIS design and performance standards; and examining the in-
corporation of the human-machine interface into ECDIS design, operation, and
performance (Alexander and Black, 1993; Alexander and Klingler, 1992; Gonin,
1993; Marine Log, 19921. Controlled experiments and tests that could not be
readily performed at sea were conducted using marine simulation (Akerstrom-
Hoffman et al., 1993; Alexander and Klingler, 1992; Gonin et al., 1993; Smith,
1993~. Afloat tests have employed a ferry boat, a 180-foot Coast Guard buoy
tender as the testbed, and a maritime academy training vessel. Although these
vessels did not exactly represent large commercial ships in terms of bridge con-
figurations, maneuvering characteristics, and manning levels, the tests that were
NAVIGATING AND PILOTING TECHNOLOGY
267
conducted yielded valuable insight for the ECDIS testbed project (Gonin, 1993;
Gonin and Crowell, 19923.
Ultimately, it appears that a technology must be field-tested aboard the pre-
cise class or type of vessel for which application is intended to determine effec-
tiveness for that type of platform in the range of operating conditions that will be
experienced. Field trials also appear to be needed for each individual installation,
because of differences among vessels, even those of the same type or class (see
Chapter 41. In select cases, it may be possible to obtain a broad base of experi-
ence with a new technology by applying it on regular routes, with regular bridge-
team personnel, over a wide range of operating conditions and for an extended
period. This approach was used to evaluate and build trust and confidence in
integrated bridge systems aboard large passenger ferries in the Baltic (Herberger
et al., 1991.) However, little if any formal performance monitoring of applied
technologies seems to be the norm. (Previous NRC assessments have consistent-
ly identified a need for more systematic assessment of safety needs and perfor-
mance of safety measures and safety data to support such assessments tNRC,
1990a, 1991a].) There appears to the committee to be a general reliance on
informal evaluation by shipboard personnel; their operational insight is essential,
but few mariners are prepared to evaluate technical performance scientifically,
especially of software, that requires a programmer's critique.
As a general practice, a new technical system is usually installed aboard a
vessel, and experience is gained with it through actual operations. A danger in
this approach is that mariners might become prematurely confident in the new
technology through its continued use at sea rather than through experience with
it in pilotage waters. Yet, it would be imprudent to rely solely on a new technol-
ogy for navigation in pilotage waters without establishing a solid basis for trust-
ing it. Therefore, despite the apparent potential of emerging technology to im-
prove navigation, a conservative approach to operational acceptance is justified,
especially with regard to the software-based technology. At the same time, the
desirability of reducing operational, economic, and environmental risk argue for
prudent acceleration of technology introduction, validation, and acceptance.
Performance Objectives vs. Equipment Mandates
Considering the pitfalls and uncertainties that may be encountered in intro-
ducing new technology, it may be advisable to develop baseline standards that
emphasize performance objectives rather than mandating specific equipment.
Performance-based standards leave room for flexibility in exceeding the require-
ments or meeting them in new ways, thereby allowing users to respond to dy-
namic changes in needs and to employ technological advances as they become
available. This approach has taken hold in civil aviation, where the trend is
toward specifying required navigation performance rather than the carriage of
designated equipment (RTCA, 1992~. The user thus may choose the navigation
268
MINDING THE HELM
configuration that satisfies both legal requirements and individual preferences.
Of course, this advantage could be lost if, to achieve a specified level of perfor-
mance, a navigator had no option but to use one particular type of equipment.
Ensuring Pilot and Watch Officer Proficiency
Among the new problems posed by advanced technologies are the subtle
difficulties involved in their practical use (Perrow, 1984~. The introduction of
radar into the fleets provides a useful example. A number of marine casualties
suggested that the watch officer or pilot sometimes became so engaged in oper-
ating the radar that awareness of the larger navigational picture was lost, result-
ing in decisions that contributed to or caused collisions. Marine simulation re-
search determined that watch officers sometimes became more absorbed with a
problem when using radar than with visual sighting or when computer-aided
decision aids were available (Aranow, 19841. This phenomenon became known
as "radar-assisted collisions" (Hebden, 1990; NTSB, 1972; Wenk, 19861. The
term is also used to refer to collisions associated with pushing the limits of safe
operations by relying on radar during periods of reduced visibility. Radar en-
ables maneuvers or speeds that would not normally be attempted if radar were
not available, but these actions may not be prudent.
Similar problems are possible with new navigation technologies such as
integrated radar and electronic charting systems if they are not used carefully.
What is more, if masters, other members of bridge teams, and marine pilots have
to become familiar with new systems through on-thejob experience, they may
find it difficult, if not impossible, to learn effectively without at the same time
compromising the integrity of piloting or watchkeeping. To minimize such a
possibility, training requirements for new technologies would need to be deter-
mined and, insofar as is practical, training provided prior to using the technolo-
gy. Alternatively, special provisions could be made to ensure that proficiency in
the use of the new technology was established without compromising safety and
performance. This level of training is employed routinely in commercial avia-
tion.
Technology-Induced Changes to Pilotage
The time-honored methods of piloting, recruitment, and on-thejob profes-
sional development may be challenged by inexorable technological changes.
With the emergence of sophisticated technologies and new bridge configura-
tions, marine pilots find themselves and their profession under increasing pres-
sure to update their practices to make use of these new capabilities.
In the past, marine pilots adapted to such changes as new technology as it
entered the commercial fleet and appeared in their service area. This was an
adequate approach, because the slow pace of change provided sufficient time for
NA VIGATING AND PILOTING TECHNOLOGY
269
pilots to become familiar with new systems. Likewise, traditional pilotage sys-
tems and pilot development programs were adequate to meet professional-devel-
opment needs. However, the existing systems and programs are not structured to
develop the needed technical skills in a rapidly changing operating environment
(see Chapters 1 through 31. Associated training issues are discussed in Chapter 7
and Appendix F.
Chances are that marine pilots will find it necessary to adapt to changing
technologies to satisfy the professional expectations of operating companies,
masters, and public authorities concerned with operational and environmental
safety. How quickly this need will develop is not certain; given the swiftness of
technological advances and the lack of universal, continuing professional devel-
opment programs, it could be soon.
