Why VTS provides information — not control
Contents
Use the links below to jump to any section:
- What VTS Actually Is
- What VTS Is Not
- Why VTS Is Often Misunderstood
- VTS Authority vs Ship Responsibility
- What Ships Are Required to Report
- How Information from VTS Should Be Used
- VTS During Pilotage
- Common VTS-Related Bridge Errors
- VTS in Accident Investigations
- Professional VTS Interaction Mindset
1. What VTS Actually Is
Vessel Traffic Services (VTS) exist to improve situational awareness within defined port and coastal areas.
Their primary functions are:
- traffic information
- navigational warnings
- coordination support
VTS operators observe traffic patterns using radar, AIS, cameras, and reports — but they do not drive ships.
VTS extends the bridge’s awareness.
It does not replace it.
2. What VTS Is Not
VTS is not:
- a traffic control authority like air traffic control
- a substitute for COLREG compliance
- responsible for ship handling decisions
- accountable for ship safety
This distinction matters.
Treating VTS as a control authority creates false security and delayed decision-making on the bridge.
3. Why VTS Is Often Misunderstood
Misunderstanding arises because VTS communication often sounds directive.
Phrases such as:
- “You are advised to…”
- “Traffic is recommended to…”
- “Vessel should consider…”
can feel like instructions.
They are not.
They are information framed for clarity, not commands transferring responsibility.
4. VTS Authority vs Ship Responsibility
Regardless of VTS involvement:
- the Master retains responsibility
- the OOW retains navigational duty
- the pilot advises but does not assume command
VTS has no authority to relieve the ship of responsibility.
If a collision or grounding occurs, responsibility remains onboard — even if VTS information was provided.
5. What Ships Are Required to Report
Reporting requirements vary by VTS area but typically include:
- vessel identity and position
- destination and intentions
- defects affecting manoeuvrability
- pilot boarding or disembarkation
- hazardous cargo status
Failure to report correctly reduces system effectiveness and can introduce risk for other vessels, not just your own.
6. How Information from VTS Should Be Used
VTS information should be treated as:
- an additional sensor
- a cross-check
- an early warning system
It should inform decisions — not make them.
Bridge teams should always ask:
- does this match what we see?
- does this affect our margins?
- do we need to adjust our plan?
VTS information is context, not direction.
7. VTS During Pilotage
When a pilot is onboard:
- VTS continues to provide information
- the pilot interprets local relevance
- the bridge monitors impact on the plan
A common failure is assuming the pilot will “handle VTS”.
This removes one more layer of cross-checking — exactly when traffic density is highest.
8. Common VTS-Related Bridge Errors
Recurring mistakes include:
- delaying action while waiting for VTS advice
- assuming VTS will warn of all dangers
- treating VTS instructions as mandatory
- ignoring VTS information that contradicts assumptions
- reducing monitoring because “VTS is watching”
VTS watches traffic.
It does not watch your margins.
9. VTS in Accident Investigations
Accident reports frequently note:
- VTS information was available
- ships received relevant warnings
- no action was taken onboard
- responsibility remained with the vessel
VTS rarely “fails”.
What fails is how its information is interpreted or acted upon.
10. Professional VTS Interaction Mindset
Professional bridge teams treat VTS as:
- a cooperative partner
- an information source
- an additional safety net
They:
- report clearly and early
- listen actively
- verify information independently
- act decisively onboard
VTS enhances situational awareness — but only the bridge can create safety.
Closing Perspective
VTS is not there to steer ships.
It exists to help ships steer themselves more safely.
When bridges expect VTS to manage risk, responsibility blurs and decisions slow.
When bridges use VTS information properly, it becomes a powerful ally —
quiet, informative, and effective.
Tags
VTS · vessel traffic service · bridge communications · port entry · pilotage · maritime safety