An empty patch in coverage, larger than the specification allows, where the sonar never saw the seabed. Holidays come from steering off line, swaths narrowing in shoal water, dropouts and obstacles. Processors find them on the daily coverage plot or with automated tools on the grid, and they are cleared with infill lines. Painters use the same word for a patch of wall the brush missed.
Two holidays at the north end where the kelp shut the outer beams down, put them on tomorrow's list.
Holidays are cheapest to fill while the boat is still in the area, which is why processing each day's data the same night pays for itself.
Also heard as
- data gap
- coverage gap
Related terms
Coverage
The portion of the seabed actually measured or imaged by a survey, expressed as a percentage of the area.
Infill
A short extra line run to fill a gap in coverage, usually to clear holidays found during processing.
Dropout
Missing pings or beams where the sonar failed to record a valid depth, leaving gaps in the data.
Flier
A spurious sounding that sticks out shoaler or deeper than the real seabed, usually from noise or a false detection.
Same word, different worlds
Pinhole, void or bare spot in a coating that leaves the metal underneath exposed.
Powder CoatingA skip, void or pinhole in the coating where bare metal is exposed.
Sealants & WaterproofingA gap, pinhole or thin spot in a membrane or coating where it fails to cover the substrate.