PCC vs PCTC: How Detection Differs
Pure car carriers and pure car & truck carriers share the casualty headlines but not the cargo geometry. The detection problem shapes itself accordingly.
The trade talks about "PCTCs" as a single vessel class. The cargo decks tell a different story — a 3,000-CEU PCC built in 2002 looks nothing like a 7,500-CEU PCTC built in 2022, and a detection layer that fits one will not fit the other.
Where the geometry diverges
- Deck clear height — PCCs run lower clearance, with hoistable decks reducing access room.
- Lane density — newer PCTCs pack vehicles tighter per square metre.
- Internal column pitch — varies enough to change sensor mounting spacing entirely.
- Ventilation architecture — older vessels rely on natural ventilation that complicates gas sensing.
What changes for the sensor grid
Sensor cells, segment master, and software are the same across vessel types. The mounting plan and cabling run are not. Roughly 60% of the deployment engineering on a new operator is in adapting the cable runs and cell pitch to the specific deck geometry — not in customising the product itself.
Sources
- DNV — "Pure Car and Truck Carriers" class notes and rule references.
- ABS — "Rules for Building and Classing Marine Vessels," Part 5C Chapter 6 (cargo decks).
- Clarksons Research — "Car Carrier Fleet Statistics 2025."
- IACS — UR S-Series, structural unified requirements relevant to vehicle decks.
Questions, answered
Are all car carriers the same for detection purposes?+
No. A 3,000-CEU PCC built in 2002 looks nothing like a 7,500-CEU PCTC built in 2022. Deck clear height, lane density, internal column pitch, and ventilation architecture all differ enough that a detection layout fitting one vessel will not fit the other.
What differs between PCC and PCTC cargo decks?+
PCCs run lower deck clearance with hoistable decks that reduce access room; newer PCTCs pack vehicles tighter per square metre; internal column pitch varies enough to change sensor spacing; and older vessels rely on natural ventilation that complicates gas sensing.
Does the detection product itself change per vessel class?+
No — the sensor cells, segment master, and software are the same across vessel types. What changes is the deployment: roughly 60% of the engineering on a new operator goes into adapting cable runs and cell spacing to the specific deck geometry, not into customising the product.
Continue the thread
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Multi-Modal Fusion: Heat, Gas, and Smoke
Each sensor modality has different blind spots. Multi-modal fusion is not a buzzword — it is the only architecture that survives the marine failure modes.
How Detection Adapts Across Ship Types
Five deployment pilots — feeder, PCTC, dual-fuel RoRo, RoPax ferry, newbuild — show what changes by ship type, and what the detection layer keeps constant.