The EchoNIMBUS-MBES Calculator helps you determine optimal survey line spacing for multibeam echo sounder missions.
System Configuration
The EchoNIMBUS-MBES system features:
- Multibeam echo sounder: Single downward-facing sensor
- Beam angle: 80° total beam width (±40° from vertical)
- Mounting: Sensor positioned at water surface level
- Coverage pattern: Fan-shaped beam creates swath perpendicular to survey line
- Operation: Continuous coverage along survey path
Interactive tool — open this page in the online manual to use it.
Usage
This calculator will help you:
- Calculate swath width based on water depth
- Determine optimal profile spacing between survey lines
- Visualize beam footprint and overlap between adjacent lines
- Plan efficient survey patterns for complete coverage
Water Depth (h)
The depth from the water surface to the bottom. This determines the beam footprint width on the seafloor.
Overlap Percentage
The desired overlap between adjacent survey lines (0-90%). Higher overlap ensures better coverage and data quality but requires more survey time. Default value is 50%.
Understanding the Results
The calculator uses these formulas to determine coverage:
Footprint Width
Width of coverage on bottom: 2 × h × tan(40°) ≈ 1.68h
Recommended Profile Width
Spacing between survey lines: Footprint Width × (1 - Overlap%)
Overlap Distance
Width of overlapping coverage: Footprint Width × Overlap%
Coverage per Pass
New coverage added per survey line: Footprint Width - Overlap Distance
Understanding the Diagram
The diagram visualizes two adjacent survey lines centered in the view:
- Profile Width: Dimension line at the top showing spacing between survey lines
- First Sensor: Orange rectangle at the water surface (left)
- Second Sensor: Grey rectangle at the water surface (right)
- Water Surface: Blue dashed line
- Bottom: Brown line (seafloor/lakebed)
- First Beam Cone: Blue cone showing 80° beam coverage
- Second Beam Cone: Grey dashed cone showing coverage of next line
- First Footprint: Green line showing coverage width
- Second Footprint: Grey dashed line showing next line coverage
- Overlap Region: Yellow/orange line highlighting overlapping area between footprints
- Water Depth: Vertical dimension line on the right edge
The diagram is centered between both survey lines to show the spacing and overlap clearly. The second line is shown with dashed grey lines to distinguish it from the primary line.