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1 INTRODUCTION

The art of pilotage has historically been defined by a

mariner’s ability to “take the conn”; the act of assuming

direct responsibility for the safe navigation of a vessel

through confined, often complex waters. This skill

demands rapid interpretation of vessel behavior,

dynamic environmental cues, and spatial positioning,

all synthesized in real time. Traditionally, this expertise

was cultivated through a long apprenticeship,

mentorship from senior pilots, and repeated exposure

to diverse operational scenarios.

Over the past two decades, however, the bridge

environment has undergone profound technological

transformation. Among the most impactful

innovations is the Portable Pilot Unit (PPU); a compact,

often tablet-based, navigation system that integrates

AIS data, tidal and meteorological inputs, under-keel

clearance models, and high-resolution chart overlays

customized for pilotage. The PPU is now a staple in

many pilotage jurisdictions, supported by the

International Maritime Organization’s (IMO) e-

Navigation strategy and recommendations from the

International Association of Marine Aids to Navigation

The Conning of a Ship in a Digitalized Environment:

Art or Science?

Y. Leclerc

Fisheries and Marine Institute of Memorial University of Newfoundland, St. John's, Canada

ABSTRACT: Maritime pilotage remains a critical safeguard for navigational safety, yet rapid advances in digital

navigation technologies, particularly Portable Pilot Units (PPUs) are reshaping how pilots perform the conning

of a ship. While PPUs enhance situational awareness and data integration, concerns persist regarding their

influence on traditional pilotage skills, human factors, and decision-making in dynamic marine environments.

This qualitative study draws on semi-structured interviews with 20 licensed maritime pilots representing 7

countries and a combined total of over 295 years of pilotage experience and over 190 years of PPU use. Participants

ranged in age from 43 to 68 years (mean 52.3), with operational experience spanning bulk carriers, container

vessels, tankers, cruise ships, and LNG carriers. 55% reported daily PPU use, while 45% used PPUs selectively.

Data was analyzed thematically, guided by a framework addressing technology adoption, situational awareness,

decision-making processes, workload, and safety culture. Findings reveal a nuanced relationship between PPU

use and pilotage performance. 85% of participants identified benefits, such as improved precision in confined

waters, enhanced pre-arrival planning, and greater confidence during low-visibility operations. Conversely, 70%

expressed concerns over potential over-reliance on digital displays, 80% noted risks to maintaining core

shiphandling skills, and only 20% considered current STCW training adequate for safe, efficient performance on

increasingly automated bridges. PPUs are best understood as complementary tools rather than replacements for

traditional pilotage expertise. Effective integration requires targeted training, regulatory guidance, and a

continued emphasis on experiential knowledge. This study highlights the need for balanced adoption strategies

that preserve human decision-making while leveraging digital advantages.

http://www.transnav.eu

the International Journal

on Marine Navigation

and Safety of Sea Transportation

Volume 20

Number 3

September 2026

DOI: 10.12716/1001.20.03.03

548

and Lighthouse Authorities (IALA) regarding

portable, pilot-centric tools.

While PPUs have demonstrably enhanced

situational awareness and decision-making precision,

they have also prompted concerns in maritime human

factors research. Studies in aviation, rail, and maritime

sectors (Markus et al., 2024; Endsley, 2017; Dekker,

2011; Chauvin, 2011) highlight the potential for

automation dependency; a phenomenon in which

cognitive and manual skill sets atrophy when

operators become over-reliant on digital aids. Within

pilotage, where high-stakes ship handling often relies

on instinctive and tacit knowledge, such dependency

could erode critical competencies.

Despite the growing body of literature on e-

navigation, there is a notable gap in empirical research

exploring how experienced pilots themselves perceive

and integrate PPUs into their operational routines, and

how this affects the art and science of conning a ship.

While technical studies focus on accuracy and system

integration, fewer works examine the intersection

between pilot expertise, digital tools, and human

factors in real-world contexts.

This study explores whether conning a vessel in

today’s digitalized environment is shifting from an art

based on tacit judgment, experiential learning, and

manual skill to a science driven by precision

instrumentation and algorithmic support. By doing so,

it seeks to inform both policy and practice, contributing

to an evidence-based approach to PPU integration that

preserves the core strengths of the pilotage profession.

Specifically, it investigates:

1. Whether PPU use impacts core conning

competencies such as positional judgment, manual

helm adjustment, and environmental cue

interpretation.

2. How experienced pilots perceive the trade-off

between operational efficiency and potential skill

erosion.

3. The implications for training, regulation, and the

evolving professional identity of marine pilots.

2 LITERATURE REVIEW

2.1 Pilotage: Tradition or Transformation

Maritime pilotage has long been recognized as a

cornerstone of navigational safety, formalized through

both national legislation and international

conventions. IMO Resolution A.960 (23) sets out the

training, certification, and operational requirements

for maritime pilots, emphasizing local knowledge,

shiphandling expertise, and independence from the

vessel’s crew in decision-making. The profession is

often described as a blend of art and science where the

science encompasses the hydrodynamics,

meteorology, and chartwork underpinning

maneuvers, while the art lies in judgment, timing, and

adaptability in dynamic marine environments. Over

recent decades, rising vessel sizes, increased traffic

density, and heightened environmental sensitivities

have compounded the complexity of pilotage tasks,

creating both the demand for and the opportunity to

integrate advanced navigational technologies.

2.2 Portable Pilot Unit Technology

Portable Pilot Units (PPUs) have evolved since the late

1990s into pilot-carried navigation and decision-

support systems that supplement and, when fitted

with independent sensors, verify shipboard

equipment. Typical configurations combine high-

precision GNSS (often dual-antenna heading), AIS

inputs, ENC-based pilotage software, and,

increasingly, real- time hydro-metocean overlays (e.g.,

tides, currents, S-100/S-102 bathymetry), giving pilots

an independent, customizable picture of the

maneuvering situation (IMPA, 2021; AMSA, 2024;

UKHO, 2022; NOAA, 2023). Although portable pilot

aids existed earlier, mainstream PPU adoption

accelerated after the early 2000s (Port Technology

International, 2006; Alexander & Casey, 2008).

Operational studies and industry evaluations report

gains in pre-arrival planning, track-keeping precision

in confined waters, and support for precise berthing,

with corresponding improvements in situational

awareness and risk control (Alexander & Casey, 2008;

Port Technology International, 2019; Clear Seas, 2024;

Westin et al., 2025). At the same time, organizations

recognize technical and human-systems limitations

latency, ship-fed AIS “pilot-plug” errors, GNSS

dropouts, and interface inconsistencies, underscoring

the need for independent sensors, verification against

bridge instruments, and formal training (AMSA, 2024;

CHIRP Maritime, 2020; Safety4Sea, 2023; San Francisco

Bar Pilots, 2015).

2.3 Human Factors in Digital Navigation

Human factors research highlights both the benefits

and risks of integrating advanced navigation tools into

safety-critical operations. Endsley’s (1995) model of

situational awareness: perception, comprehension, and

projection, remains central to understanding pilotage

in a digital environment. While PPUs can enhance the

projection stage by providing predictive trajectory and

under-keel clearance models, they can also

inadvertently shift attention from external visual cues

to screen-based information, leading to a phenomenon

known as cognitive tunneling (Markus et al., 2024).

Additionally, Consistent with skill-decay literature,

infrequent manual maneuvering in highly automated

bridges can erode core shiphandling skills over time;

similar effects are documented in other safety-critical

domains under automation (manual-control ‘out-of-

the-loop’ problems and degraded manual

proficiency).” (Endsley & Kaber, 1997; Casner, Geven,

& Williams, 2014; Klostermann et al., 2022; AIDR

review, 2021; see also maritime evidence on ECDIS

over-reliance).

2.4 Gaps in Current Research

While numerous technical evaluations of PPU accuracy

and hardware/software performance exist, peer-

reviewed scholarship on pilots’ lived experiences with

PPUs in real operating contexts remains comparatively

limited. Technical and vendor-oriented assessments

dominate the literature (Port Technology International,

2006, 2019; Adnav/Navicom Dynamics, n.d.) whereas

only a handful of recent studies directly examine how

pilots experience tool-assisted navigation and how this

interacts with traditional pilotage skills and judgment.

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Notable exceptions include a mixed-methods survey of

69 Swedish pilots on trust, training, and use of PPU

predictor automation (Westin & Lundberg, 2025) and a

WMU dissertation exploring PPU effects on pilots’

situation awareness (Kuwornu, 2023). Practitioner and

safety/usability work around digital navigation (e.g.,

Nautical Institute features; MAIB & DMAIB’s ECDIS

usability study; CHIRP incident analyses) further

underscores that the boundary between tool-assisted

navigation and embodied expertise remains under-

explored in formal scholarship. This research is

designed to address that gap.

Although there are many technical evaluations of

PPU hardware/software performance (e.g.,

GNSS/heading/ROT accuracy, pilot-plug vs.

independent sensors), peer-reviewed work that

captures pilots’ lived experience with PPUs in real

operations is comparatively sparse.

Technical/performance-oriented pieces dominate (e.g.,

Port Technology assessments; vendor and selection

guides), while only a handful of recent studies probe

how pilots actually experience and make sense of tool-

assisted navigation and how that interacts with

traditional pilotage skills and judgment.

This research is positioned to close that gap by

foregrounding pilots’ real-world experiences, decision

processes, and skill interaction with PPUs, rather than

treating PPUs purely as technical artifacts.

3 METHODOLOGY

3.1 Research Design

This study adopted a qualitative, exploratory design

using semi-structured interviews to capture the

nuanced perspectives of active marine pilots on PPU

use. A qualitative approach was selected to capture the

depth, complexity, and contextual richness of pilotage

practice, particularly the interplay between traditional

skills and emerging digital tools.

3.2 Participants and Recruitment

Twenty licensed maritime pilots from 7 different

countries, ports and operational contexts participated

in the study. Selection criteria required participants to:

− hold a valid pilotage license,

− have a minimum of five years of pilotage

experience, and

− have operational familiarity with PPUs.

Participants were recruited via professional

pilotage associations and snowball sampling, ensuring

a diverse representation of geographical regions, vessel

types, and operating environments.

Participants’ ages ranged from 40 to 66 years, with

an average age of 52.35 years. All participants were

male. Professional experience as a pilot ranged from 2

to 28 years (average 14.93 years).

Nationalities included:

− Canadian: 8 participants

− Australian: 3 participants

− Irish: 2 participants

− British: 4 participants

− Indian: 1 participant

− Russian: 1 participant

− Dutch: 1 participant

This diversity ensured representation across

different regulatory regimes, training models, and

operational environments.

Figure 1. Provides an overview of participants’ nationality

(source: the author).

3.3 Participants Demographics

This qualitative study draws on semi-structured

interviews with 20 licensed maritime pilots

representing 7 countries and a combined total of over

295 years of pilotage experience and over 190 years of

PPUs’ usage. Participants ranged in age from 43 to 63

years (mean 52.3), with operational experience

spanning bulk carriers, container vessels, tankers,

cruise ships, and LNG carriers. Fifty five percent

reported daily PPU use, while 45% used PPUs

selectively.

Figure 2. Provides the 20 participant’s age (source: the

author).

Data were analyzed thematically, guided by a

framework addressing technology adoption,

situational awareness, decision-making process,

workload, and safety culture.

3.4 Data Collection

Interviews were conducted between January 2025 and

July 2025, via secure video conferencing platforms.

Each interview lasted between 45 and 90 minutes and

was audio- recorded with participant consent. The

interview focused on four key domains: operational

experiences with PPUs, perceived benefits and

challenges, impacts on situational awareness and

shiphandling, and views on training and regulation.

Transcripts were anonymized and assigned unique

identifiers (e.g., P07, Canadian, 8 years as pilot).

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3.5 Data Analysis

Data were coded using the thematic framework

developed manually, which included key categories

such as:

1. Enhanced Situational Awareness.

2. Perceived Risks of Over-Reliance.

3. Impact on Traditional Shiphandling/Conning

Skills.

4. Differences in PPU use.

5. Training and policy considerations.

3.6 Ethical Considerations

Ethics approval was obtained from Memorial

University’s Interdisciplinary Committee on Ethics in

Human Research, and all participants provided

informed consent prior to participation. Identifying

details were removed from transcripts, and all data

were stored securely in compliance with institutional

guidelines.

3.7 Sample Size Justification

This study included 20 licensed maritime pilots as

participants. The number was determined by

balancing the specialised nature of the target

population with the methodological principles of

qualitative inquiry. Maritime pilots constitute a small

and highly specialised professional group, making

large-scale sampling impractical. Recruitment was

limited to pilots with at least five years of experience

and operational familiarity with Portable Pilot Units

(PPUs), which further constrained the eligible pool.

The sample of 20 achieved diversity in geography and

vessel operations, representing pilots from seven

countries and covering a range of vessel types,

including bulk carriers, container ships, tankers, LNG,

and cruise vessels. Each participant engaged in an in-

depth semi-structured interview lasting 45–90 minutes,

producing rich and detailed accounts that enabled

rigorous thematic analysis.

Importantly, thematic saturation was reached by

the 17th–18th interview, with no new substantive

insights emerging thereafter. This aligns with accepted

guidance in qualitative methodology, where saturation

is commonly achieved between 12 and 20 participants

in relatively homogeneous expert groups (Creswell,

2018; Guest et al., 2006). Comparable studies in

maritime human factors and navigation technology

have similarly employed samples of 12–30

participants, establishing precedent for this range (e.g.,

Westin & Lundberg, 2025; Kuwornu, 2023).

Finally, limiting the study to 20 participants also

respected ethical and practical considerations,

acknowledging pilots’ demanding work schedules and

ensuring voluntary participation without undue

burden. On this basis, the sample size was deemed

appropriate, sufficient, and methodologically justified

for the study’s objectives.

4 FINDINGS

Thematic analysis of the 20 interviews revealed five

overarching themes relating to the integration of

Portable Pilot Units (PPUs) into maritime pilotage

practice: (1) Enhanced Situational Awareness, (2)

Perceived Risks of Over-Reliance, (3) Impact on

Traditional Shiphandling Skills, (4) Differences in PPU

use and (5) Training and Regulatory Considerations.

These themes reflect a nuanced balance between

perceived technological advantages and concerns for

preserving the “art” of pilotage. Eighty-five percent of

participants identified benefits such as improved

precision in confined waters, enhanced pre-arrival

planning, and greater confidence during low-visibility

operations. Conversely, 70% expressed concerns over

potential over-reliance on digital displays, 80% noted

risks to maintaining core shiphandling/conning skills,

and only 20% considered current STCW training

adequate for safe, efficient performance on

increasingly automated bridges.

Each theme is presented below with representative

participant quotes to illustrate perspectives and

experiences.

4.1 Enhanced Situational Awareness

Participants consistently highlighted the enhanced

situational awareness provided by PPUs. High-

resolution charts, real-time AIS updates, and

customizable overlays allowed pilots to make

informed decisions, especially in low-visibility

conditions or complex port approaches.

Eighteen participants (90%) reported that PPUs

significantly improved their ability to assess vessel

position, speed, and trajectory, particularly in

challenging environmental or traffic conditions. The

predictive features, such as track overlays and under-

keel clearance modeling, were frequently highlighted

as valuable aids to decision-making.

For example, one participant noted: “The PPU gives

me an immediate visual on under-keel clearance, tidal

flow, and the ship’s exact position. It’s like having a

second set of eyes that never blink” (P08, Australian, 21

years as pilot).

Others emphasized the efficiency gains: “When I’m

bringing in a 200,000-tonne bulk carrier in fog, the

PPU’s track predictor is invaluable—it lets me

anticipate how the ship will respond before I even put

the rudder over.” (P4, 7 years as pilot).

4.2 Perceived Risks of over-Reliance Limitations

Despite the benefits, (70%) of participants expressed

concern that growing dependence on PPUs could

create vulnerabilities if the system failed or data

became unreliable. While most emphasized, they

maintained visual navigation as the primary reference,

some acknowledged that the convenience of digital

precision could tempt over-reliance.

Participants expressed caution regarding over-

reliance on PPUs as several pilots warned that

technology can fail or provide misleading data if not

cross-checked with visual and radar observations.

One participant warned: “Technology is brilliant

until it isn’t—when it freezes, you have seconds to

switch back to the old way.” (P8, 21 years as pilot).

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One experienced pilot cautioned: “Electronics can

fail when you least expect it. If you haven’t been

keeping your head out the window, you’re already

behind” (P12, 16 years as pilot).

Others noted the danger of complacency: “I’ve seen

younger pilots follow the PPU line blindly without

checking the actual set and drift. That’s a recipe for

trouble” (P15, 21 years as pilot); “If you start flying the

ship off the screen instead of out the window, you’re

already in trouble.” (P11, 20 years as pilot).

Finally, several pilots emphasised the importance of

using the PPU as a cross-check tool rather than the sole

basis for decision-making.

One participant stressed: “We don't teach pilots

how to do all of those things well. To manage both

managing that reliance on visual navigation, which

should be always your primary navigation, and cross-

referencing your PPU and using all of its strengths

without becoming over-reliant and then always

circling around or using the ship's electronic aids with

ECTUS and the radar ARPA.” (P10, 15 years as pilot).

4.3 Impact on Traditional shiphandling/Conning Skills

A recurring concern was the gradual erosion of

traditional ship-handling instincts. Sixteen participants

(80%) voiced concern that pilots might develop a

dependence on PPUs at the expense of manual

shiphandling skills, particularly those related to visual

cues, feel for the vessel’s momentum, and

hydrodynamic effects in confined waters.

Several participants linked reduced visual

navigation practice to a decline in their ability to 'feel'

the vessel’s behavior.

One senior pilot explained: “Before PPUs, I could

sense a ship’s sheer or sluggishness instantly. Now, I

catch myself checking the screen instead of trusting my

senses” (P01, 24 years as pilot).

Another reflected: “We still teach visual transit

bearings, but most pilots now default to digital

overlays. It’s efficient, but we’re losing a craft” (P09, 28

years as pilot).

One pilot said: “I see a lot of my older colleagues

now they rely on these to maneuver even after going

up the river on a 90 meter coastal vessel you know they

feel they can't function properly without it and it's

losing these core skills we have as a pilot and one thing

that concerns me is that at some point you'll go from a

professional to an operator and I think pilots we really

need to be at the top of our game.” (P12, 16 years as

pilot).

Another participant affirmed: “I did notice a

decrease in my skills once fully licensed and carrying

and using the PPU on every assignment. I could feel I

was losing the feel for piloting, the ability to look out

the window, or over the wing and gauge speeds, ROT’s

and if I was passing clear of intended shoals and

staying on my planned track.” (P5, 6 years as pilot).

Others stated: “You can see it in the new guys—

they’re good with the software but less confident if you

take it away.” (P15, 21 years as pilot).

“In my early years, I learned to read the ship

through the wheel and the wake. If we stop teaching

that, we lose something essential.” (P6, 7 years as pilot).

4.4 Differences in PPU Use

Generational attitudes toward PPU use varied

significantly. Younger pilots were generally more

comfortable with technology, often integrating

multiple digital tools simultaneously. Older pilots

tended to use PPUs as supplementary aids rather than

primary navigation sources.

As one mid-career pilot observed: “The guys in

their 30s and 40s use the PPU for everything—they

navigate, log, and even communicate through it. The

older generation keeps one eye on the screen and the

other on the horizon” (P17, 15 years as pilot).

A senior participant summed it up: “It’s not about

age, it’s about mindset. Some veterans embrace the

tech, others stick to tried-and-true methods” (P05, 6

years as pilot).

Training and Regulatory Considerations only 20%

considered current STCW training adequate for safe,

efficient performance on increasingly automated

bridges. While most pilots received initial

familiarization from their organizations, there was

limited formalized, standardized training on advanced

PPU functions or troubleshooting.

One participant said: “We’re all learning on the

job—there’s no IMO manual for how a pilot should use

a PPU.” (P1, 24 years as pilot).

Others highlighted inconsistency in

training/familiarization package: “It’s inconsistent. In

some ports, the pilots get high-end training, in others

you just pick it up as you go.” (P17, 17 years as pilot).

Also, participants identified a lack of standardized

training and policy guidance for PPU use. In many

jurisdictions, PPU proficiency is self-taught or learned

informally through peer mentoring.

One participant explained: “Our authority doesn’t

mandate PPU training; it’s up to us to figure it out.

That’s fine for experienced pilots, but risky for new

ones” (P14, 11 years as pilot).

Others suggested formal certification: “If we’re

going to rely on these tools, there should be a standard

curriculum and competency check” (P19, 18 years as

pilot).

Participants called for more structured, scenario-

based training and inclusion of PPU operational

guidelines in national pilotage standards.

5 DISCUSSION

This study set out to explore how maritime pilots

integrate Portable Pilot Units (PPUs) into their

operational practice and how this affects the art and

science of conning a ship.

The findings confirm that PPUs are deeply

integrated into modern pilotage, offering tangible

benefits in precision, safety, and communication.

However, the technology also introduces risks

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associated with over-reliance and skill degradation.

These themes align with broader human factors

literature, which warns that automation can erode core

competencies when not balanced with manual practice

(Endsley, 2017; Parasuraman & Riley, 1997).

Generational differences suggest that training

approaches must be adaptive, leveraging younger

pilots’ digital fluency while ensuring they develop and

maintain traditional conning skills. Likewise, older

pilots may benefit from targeted digital training to

optimize PPU integration without compromising their

reliance on visual and environmental cues.

Policy implications are important. Without

standardized training and competency checks, PPU

use remains inconsistent, potentially undermining

safety in certain contexts. International bodies such as

IMO and IALA could play a role in defining minimum

training requirements, while pilotage authorities tailor

programs to local conditions.

5.1 Enhanced Situational Awareness and the Science of

Pilotage

Most participants emphasized that Portable Pilot Units

(PPUs) materially improve real- time situational

awareness, particularly in demanding conditions such

as strong set and drift, restricted visibility, traffic

compression, or tight under-keel margins.

In Endsley’s (1995) terms, PPUs enhance all three

levels of situational awareness: perception (Level 1)

through high-integrity position/heading and layered

data (electronic navigational charts, tides, currents,

aids to navigation); comprehension (Level 2) via clear

symbology, clearing lines, safety contours, and under-

keel clearance visualizations; and most notably

projection (Level 3) through predictors that forecast

future track, rate-of-turn, and clearance envelopes.

This forward look extends the pilot’s temporal horizon,

supporting earlier and more precise interventions,

adjusting engine or thruster settings, refining wheel-

over points, or staging tug inputs before small errors

amplify. Consistent with Barnett et al. (2018),

participants felt this capability strengthens the

“science” of pilotage by anchoring decisions in

quantifiable trends rather than retrospective cues

alone.

Benefits also accrue at the team level. When PPUs

are used to share a common picture with the master,

bridge team, and tugs, they can sharpen Bridge

Resource Management: intentions are visible,

predicted turns are transparent, and deviations from

plan are detected sooner. Several pilots highlighted the

value of data capture and replay for post-passage

debriefs and mentoring turn limits, speed profiles, and

approach paths become teachable patterns rather than

anecdote. Where S-100 hydro-met layers (e.g., high-

resolution bathymetry, real-time water levels, and

surface currents) are available, pilots reported more

confident decision-making on dynamic under-keel

clearance and meeting/overtaking strategies in narrow

channels.

At the same time, reliance on PPU-based predictive

modeling raises important redundancy and trust-

calibration considerations. International guidance (e.g.,

IMO, 2021) stresses that no single system should

become the sole source of truth. Participants reflected

this doctrine in practice by conducting independent

cross-checks, validating PPU indications against visual

ranges and leading lines, radar ranges and bearings,

gyrocompass and rate-of-turn instruments, and echo

sounder trends. They also described routine pre-use

verification (datum alignment, heading and latency

checks, antenna placement) and integrity monitoring

in use (watching quality flags, age of data, and alarm

thresholds). Where possible, pilots preferred

independent sensors (dual-antenna GNSS for heading,

standalone rate-of-turn) to avoid artifacts from the

ship’s pilot-plug feed. Finally, many advocated

periodic PPU-out segments and degraded-mode drills

to maintain manual conning fluency and guard against

complacency or cognitive tunneling. Taken together,

these practices allow organizations to capitalize on

PPUs’ data-driven strengths while preserving the

resilient, cue-rich competencies at the heart of safe

pilotage.

5.2 Perceived Risks of Over-Reliance: A Human Factors

Concern

The risk of “flying the ship off the screen” echoes Grech

et al.’s (2019) caution about cognitive tunneling in

high-technology navigation: attention collapses onto

the display and its predictors at the expense of parallel

cues from the vessel, environment, and bridge team.

Participants did not reject Portable Pilot Units (PPUs);

rather, they consistently framed them as supplemental;

excellent for precision and shared situational

awareness, not primary.

This stance reflects a resilience mindset: an explicit

expectation that technology can degrade or fail at

critical moments (e.g., latency spikes, GNSS multipath,

pilot-plug offsets, stale S-100 layers), and that visual

judgment, conning “feel,” and experiential cues (range

marks, shoreline parallax, wind on hull, tug geometry)

remain indispensable fallbacks.

From a human-factors perspective, over-reliance

brings two intertwined hazards. First, out- of-the-loop

effects: when automated aids perform most routine

tracking and prediction, pilots’ manual schemas

atrophy, making infrequent manual intervention

slower and more error-prone. Second, confirmation

bias: pilots may search for cues that agree with the

display rather than interrogating conflicts (e.g.,

predictor shows clearance while visual bearings imply

set). These dynamics parallel well-documented

patterns in aviation and rail, where heavy dependence

on digital aids has been linked to erosion of adaptive

problem- solving during system outages and mode

confusions (cf. Salmon et al., 2020). In pilotage, the

practical manifestation is subtle skipping a clearing

bearing, deferring a visual cross- check, or accepting a

smoothed rate-of-turn until a compound scenario

(variable current + traffic compression + sensor lag)

exposes the gap.

Mitigations expressed by participants align with

best-practice human-factors controls. At the

procedural level: (i) pre-use verification as ritual

(datum/heading/latency checks, antenna placement);

(ii) in-use cross-checks at defined intervals

(visual/radar/gyro, clearing lines, lead marks); (iii)

PPU-out segments during benign legs to preserve

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manual conning; and (iv) explicit disengagement rules

(“predictor off” triggers) when cues conflict. At the

training level: scenario-based drills that induce

degraded modes (dropouts, offsets, contradictory

layers), coached attention-shifting between screen and

scene, and structured debriefs that weight tacit cues,

throttle cadence, bow response, tug orders, alongside

electronic error bands.

Finally, organizations can monitor usage quality

(not just usage rate) to guard against drift into

dependency: frequency of logged visual cross-checks,

time-to-detect sensor anomalies, adherence to “PPU-

out” recency, and incident/near-miss analyses that

classify display-led vs. cue-led decisions. Taken

together, these measures maintain PPUs as a force

multiplier while protecting the adaptive, cue-rich

expertise that remains central to safe pilotage.

5.3 Training Impact on Traditional

Shiphandling/Conning Skills: Preserving the Art

The concern that younger pilots may become less

proficient in manual shiphandling when Portable Pilot

Units (PPUs) are always present mirrors findings from

other transport domains, where automation reduces

routine exposure to hands-on control. Endsley (2016)

describes an “automation conundrum,” wherein

increasing system autonomy often diminishes

operators’ situational awareness, thereby weakening

their capacity to take over manual control during

unanticipated or critical situations. Skill decay is most

pronounced when technology executes the majority of

routine tasks; as a result, the rare occasions that

demand manual intervention are more error-prone

and cognitively taxing. In pilotage, this risk manifests

as diminished sensitivity to tacit cues, the feel of the

hull in cross-winds, subtle squat or bank effects in

shallow bends, the tempo of engine and thruster

responses, or the cadence of tug communications, that

collectively underpin the “art” of conning. When these

cues are continually filtered through digital overlays,

pilots can unintentionally offload perception and

prediction to the device, weakening the internal mental

models that support rapid, resilient decisions in

degraded or novel situations.

Participants’ advocacy for PPU-free practice

directly addresses this risk and aligns with

recommendations that periodic reversion to non-

digital navigation helps preserve core competencies

(Lutzhoft et al., 2019). This is particularly critical given

the pilotage profession’s reliance on tacit, embodied

knowledge a hallmark of its “art.

In practical terms, this means designing a

deliberate-practice curriculum that includes:

− scheduled manual-only transits under benign

conditions with clear go/no-go criteria;

− simulator sessions that limit or “fail” digital aids

(e.g., latency, dropouts, sensor offsets) to force

reliance on visual ranges, clearing bearings, rates of

turn, and tug geometry;

− degraded-mode drills (night, rain, glare, traffic

compression) with explicit rules for when to

disengage or re-engage predictors; and

− structured debriefs using track replays that focus on

visual cues, throttle/thruster modulation, and

communications timing rather than solely on

electronic error bands. Competence should be

evidenced with observable metrics such as track-

keeping without predictors in a known bend,

controlled speed profiles through shallow reaches,

smooth tug orders at critical points, and consistent

cross-checks against lighthouse bearings and

leading lines.

To support generational differences, training can

leverage younger pilots’ digital fluency while

embedding routines that rebuild manual schemas: pre-

arrival plans drafted from first principles, mental ETA

checks against visual cues, and explicit “PPU as

confirmatory aid” protocols during key phases.

Conversely, targeted digital upskilling for senior pilots

(e.g. sensor validation, S-100 data interpretation, alarm

discipline, and cyber hygiene) can optimize PPU

integration without displacing their reliance on

environmental cues. A balanced regime recency

requirements for manual conning, periodic check-

rides that prohibit predictor use during defined legs,

and reverse-mentoring pairs (junior– senior) for shared

best practice, helps ensure that technology augments

rather than erodes the embodied expertise that has

always distinguished the profession’s craft.

5.4 Differences in PPU Use

Across pilotage organizations, two clear patterns

emerge. Continuous (primary) use means the Portable

Pilot Unit is powered and referenced for most phases:

approach, channel transit, and berthing, often with an

independent sensor stack (dual-antenna

GNSS/heading, rate-of-turn) and predictors displayed

as the main conning view. Benefits include a stable

common picture for the bridge team and tugs, precise

turn and speed control in confined water, dynamic

under-keel clearance awareness, and consistent data

capture for debriefs. The trade-offs are a higher risk of

automation dependency and “out-of-the-loop” effects

if cross-checks slacken, plus the need for disciplined

pre-use verification (datum, latency, heading

alignment) and robust cyber/data hygiene.

By contrast, situational (secondary) use means

pilots power up the PPU only for specific legs or

conditions: bar crossings, night entries, poor visibility,

strong set/currents, first-port calls or treat it as a

confirmatory aid alongside visual/radar/gyro cues.

This approach tends to preserve manual conning skills,

reduce cognitive clutter in straightforward conditions,

and foreground local, tacit cues (range marks,

shoreline parallax, vessel “feel”). The drawbacks are

inconsistency (variable set-up quality and recency),

switching costs when activating the PPU mid-transit,

and a higher chance of under-utilizing predictors or

UKC tools when they could add safety margin.

Which pattern dominates often reflects context:

channel geometry and traffic mix; availability of S-100

layers (S-102 bathymetry, S-104 water levels, S-111

currents); policy on sensor independence vs. ship’s

pilot plug; organizational doctrine (mandatory pre-use

checks, cross-check intervals); equipment

ownership/maintenance (authority-issued kits vs.

personal), and training culture (simulator exposure to

degraded modes). Generational factors can amplify

differences: digitally fluent pilots may default to

554

continuous use; highly experienced pilots may lean on

situational use to keep visual conning sharp.

A balanced doctrine can reconcile these modes.

Define phase-based expectations (e.g., “PPU-primary”

for precision legs; “PPU-assist” for open reaches) and

trigger conditions that make PPU use mandatory

(deep-draft or marginal UKC, visibility below X,

currents above Y, first call, equipment outages).

Standardize pre-use (antenna placement,

datum/heading/latency checks), in-use cross- checks

(visual bearings, radar ranges, gyro/ROT), and post-

passage debriefs with track replay. Train both ways:

regular PPU-out drills to maintain manual proficiency

and degraded-mode scenarios (dropouts, offsets, stale

data) to prevent blind trust when PPUs are primary.

Finally, monitor usage quality, not just usage rate, with

indicators like cross- check frequency, deviation

control in bends without predictors, time-to-detect

sensor anomalies, and adherence to alarm discipline.

This approach keeps PPUs as a force multiplier while

protecting the core craft of pilotage.

5.5 Training and Regulatory Considerations

The absence of standardized Portable Pilot Unit (PPU)

training and operational guidelines confirms the gap

identified by leading bodies (e.g., IALA) and mirrors

participants’ calls for structured, scenario-based

instruction. While the International Maritime

Organization and many national pilotage standards

acknowledge PPUs as complementary aids, they

generally stop short of prescribing how they should be

configured, verified, and used nor do they define

competency levels across a pilot’s career. In practice,

proficiency is often attained informally, resulting in

variable depth, inconsistent verification, and uneven

approaches to risk. This variability is especially evident

in high-consequence contexts (confined waters,

bar/river transits, night or degraded-sensor operations)

where pilots rely on predictors, real-time

tides/currents, and S-100 overlays. Participants

emphasized that formalization should prioritize

hands-on, scenario-rich training that reflects real

bridge conditions, human-automation pitfalls (latency,

dropouts, over-trust), and cross- checks against

shipboard instruments.

A pragmatic evolution would pair minimum global

baselines with local tailoring. At the baseline,

authorities could adopt a modular framework

covering:

(1) Initial/type-specific training on equipment

classes, sensor independence, accuracy/limitations,

and cyber/data hygiene; (2) Recurrent training using

simulator and sea-ride scenarios (GPS multipath, pilot-

plug offsets, predictor failure, ENC/S-102

discrepancies, alarm discipline, loss of comms); (3)

Operational SOPs for pre-use checks (antenna

placement, datum checks, latency/heading validation),

in-use verification (clearing lines, cross bearings, visual

cues), and post-passage debriefs; (4) Competency

assessment via task books, observed line-trips,

simulator assessments, and periodic proficiency

checks; and (5) Assurance & audit KPIs for usage

quality (not merely usage rate), incident/near-miss

learning loops, and vendor- neutral performance tests.

Locally, pilotage authorities would adapt procedures

to channel geometry, traffic mix, met-ocean conditions,

hydrographic currency, and communications

bandwidth, ensuring PPUs enhance, not replace,

traditional conning techniques and local knowledge.

Crucially, any training standard should embed

human-factors objectives: maintaining manual

shiphandling skills; managing cognitive load and “out-

of-the-loop” risks; setting rules for automation

engagement/disengagement; and using PPUs to

support team resource management with masters,

bridge teams, and tugs (shared mental models,

common picture, clear call-outs). To support

generational differences, curricula can leverage digital

fluency among newer pilots while deliberately

reinforcing visual navigation and mental modeling; for

senior pilots, targeted digital upskilling and guided

practice can optimize integration without eroding

established cue-based expertise. Taken together, a risk-

based, modular regulatory framework, minimum

competencies, documented SOPs, recurrent

assessment, and independent assurance, would

promote uniform safety outcomes and interoperability,

while preserving the flexibility needed to reflect local

navigational realities.

5.6 Limitations

The study’s qualitative design and relatively small,

geographically diverse sample limit the extent to which

findings can be generalized across the broader pilotage

profession. While diversity enriched the data by

providing multiple perspectives, it also introduced

heterogeneity that may reduce consistency in

interpretation. In addition, the reliance on self-reported

experiences carries the risk of recall bias, selective

memory, or the influence of individual perception, all

of which may shape the accuracy of responses.

Variations in PPU models, levels of digital integration,

and port infrastructure across regions further

complicate the transferability of results, as operational

contexts differ widely. Finally, the study did not

incorporate direct observational or quantitative

performance data, which could have provided an

additional layer of validation to complement the pilots’

narratives. These limitations also highlight valuable

avenues for further research. Future studies should

consider:

1. Conducting quantitative analyses that link PPU

usage to incident rates, efficiency measures, or

maneuver performance metrics, thereby

complementing qualitative insights with objective

data.

2. Comparing perspectives across different levels of

digital adoption, examining whether pilots who

rely heavily on PPUs report distinct challenges or

benefits compared with those using them more

selectively.

3. Exploring the impact of PPUs on bridge team

dynamics and communication, particularly how

digital tools influence collaboration, situational

awareness, and authority gradients.

4. Investigating long-term skill retention among pilots

trained in both digital and traditional methods to

assess whether reliance on technology accelerates or

mitigates the erosion of manual shiphandling

expertise.

555

5.7 Recommendations

While offering substantial benefits, PPUs also

introduce challenges, including risks of over-reliance,

increased cognitive load, and the gradual erosion of

traditional shiphandling skills.

5.7.1 General recommendations

To safeguard this balance between technological

support and professional expertise, the following

recommendations are proposed:

1. Develop standardized, mandatory PPU training

programs that include both technical and manual

navigation components.

2. Incorporate regular skill-retention exercises into

pilot training, focusing on visual and

environmental navigation techniques.

3. Encourage cross-generational mentorship to blend

digital proficiency with traditional expertise.

4. Promote policy frameworks through IMO and

IALA to harmonize PPU best practices globally.

Ultimately, the future of conning in a digitalized

environment will depend on the profession’s ability to

integrate advanced tools without losing the human

touch that has defined pilotage for centuries.

5.7.2 Practical recommendations For Pilots

1. Maintain PPUs as a supplementary decision aid, not

as the primary navigational reference.

2. Engage in regular PPU-free shiphandling exercises

to sustain manual navigation skills.

3. Configure display settings to reduce cognitive load

and prioritize relevant data.

5.7.3 For Training Providers

1. Integrate scenario-based training modules

combining PPU-assisted and non-digital

navigation.

2. Include troubleshooting and degraded-mode

operations in simulator sessions.

3. Foster understanding of human factors in digital

navigation, including cognitive load management.

5.7.4 For Regulator and Pilotage Authorities

1. Develop standardized operational guidelines for

PPU usage in pilotage.

2. Establish competency frameworks for PPU

proficiency and revalidation.

3. Encourage harmonized training across pilotage

districts to reduce variability in skill levels.

6 CONCLUSION

This study set out to examine whether conning a vessel

in the digital age is more art or science. The evidence

suggests it is now a hybrid discipline, part intuitive

craft, part data- driven process. PPUs have become

indispensable in many pilotage contexts, enhancing

precision and situational awareness, but they should

be seen as augmenting rather than replacing the

mariner’s eye, instinct, and judgment. To ensure safe

navigation/conning, pilots must cultivate a balanced

integration of human factors awareness, traditional

shiphandling skills, and proficiency in digital

navigation tools. (e.g. see figure below).

Figure 3. Conceptual Model of PPU Integration in Pilotage

(source: the author)

The findings suggest that PPUs, when integrated

thoughtfully, can enhance maritime safety without

diminishing the human expertise that defines pilotage.

Achieving this balance requires deliberate training,

regulatory foresight, and a commitment to preserving

the profession’s core competencies.

6.1 Limitations

The study’s qualitative design and relatively small,

geographically diverse sample limit the extent to which

findings can be generalized across the broader pilotage

profession. While diversity enriched the data by

providing multiple perspectives, it also introduced

heterogeneity that may reduce consistency in

interpretation. In addition, the reliance on self-reported

experiences carries the risk of recall bias, selective

memory, or the influence of individual perception, all

of which may shape the accuracy of responses.

Variations in PPU models, levels of digital integration,

and port infrastructure across regions further

complicate the transferability of results, as operational

contexts differ widely. Finally, the study did not

incorporate direct observational or quantitative

performance data, which could have provided an

additional layer of validation to complement the pilots’

narratives. These limitations also highlight valuable

avenues for further research. Future studies should

consider:

1. Conducting quantitative analyses that link PPU

usage to incident rates, efficiency measures, or

maneuver performance metrics, thereby

complementing qualitative insights with objective

data.

2. Comparing perspectives across different levels of

digital adoption, examining whether pilots who

rely heavily on PPUs report distinct challenges or

benefits compared with those using them more

selectively.

556

3. Exploring the impact of PPUs on bridge team

dynamics and communication, particularly how

digital tools influence collaboration, situational

awareness, and authority gradients.

4. Investigating long-term skill retention among pilots

trained in both digital and traditional methods to

assess whether reliance on technology accelerates or

mitigates the erosion of manual shiphandling

expertise.

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