Definition
Downflooding is the progressive entry of water into a vessel through openings that are not intended to remain watertight once the vessel heels, trims, or loses freeboard.
Why it matters
Downflooding often turns a recoverable heel or deck-edge immersion event into a loss. Once water reaches machinery spaces or other internal compartments, stability deteriorates rapidly.
Common entry points
- Engine room vents and exhausts
- Open hatches and deck access covers
- Doors left open below the weather deck
- Damage openings near the waterline
Typical pattern in accident reports
- A vessel heels, trims, or is damaged.
- Water enters through an exposed opening.
- Free-surface and flooding effects reduce residual stability.
- The vessel capsizes or sinks before corrective action succeeds.
Related
Related incidents
Accidents linked to this concept are grouped by vessel type.