Trawlmaster for Single Trawls

 

Single Rig with Sensor

Trawlmaster
Cathc Sensor
Door Sensor

Overview
Are my doors trawl wires marked correctly?  Is my trawl spread optimally?  Is the trawl on bottom?  The Trawlmaster provides the answers by attaching smallest robust trawl sensors to the gear.  All information is transmitted to the vessel wirelessly.

Doorspread
The distance between the doors reduces fuel by allowing you to keep the optimal door spread.

  • Adjust vessel speed to keep optimal doorspread.
  • Indicates when your doors have crossed.
  • Detects when your door has fallen or is stuck.

 

Doorspread

Trawl Warp Measurement
The distance from the vessel to EACH trawl door.

  •  Accurately measures your trawl wires to within 1/2 meter.
  • Avoids measuring your trawl wires on shore.
  • Indicates the adjustment in cross current to “square” the doors.

Trawl Wire Lengths

Door Angle
The heel angle (inward/outward lean) and pitch angle (upward/downward pitch).

  • Set the trawl doors for optimal spread and optimal fuel consumption
  • Instantly indicates if you shoot too much trawl wire as the door heels over.
  • Indicates when the doors are on bottom.

Single Trawl Door Angle

Trawl Door Height
Trawl door height monitors the distance from the door to the seafloor.

  • Height is critical to the successful operation of semi pelagic doors that fly very close to the bottom.
  • Equal door heights translate to optimal fishing.

Door Height

Headline Height
Indicates the distance from the headline to the seafloor.

  • Add a footline slave to receive footgear clearance.
  • Indicates when your trawl is on bottom.
  • Allows you to raise and lower the headline depending on species and trawling conditions.

Headline Height

Catch
Indicates when the cod-end is full.

  • Only take back what you can handle onboard.
  • Prevents hauling back a trawl that is only half full.
  • Provides a better indication of exactly where the fish are in the tow.

Single Trawl Catch

Bottom Contact
Indicates if the trawl is on bottom.

  • Fishing is greatly reduced once your trawl comes off bottom.
  • Indicates if your speed into the current is taking the trawl off bottom.
  • If you do not shoot enough trawl wire, the trawl will not be on bottom.

Single Trawl Bottom Contact

Depth & Temperature
Depth sensors indicate the distance from the surface to the doors/trawl.  Temperature is measured at the trawl.

  • When mid watering, trawl depth allows you to place the trawl at depth of the fish.
  • When bottom trawling, depth will indicate when the gear is on bottom.
  • Locate bigger schools and avoid by-catch with temperature.

Single Traw; Depth and Height

Grid Angle
 Indicates angle of the sorting grid.

  • If your grid is not at the right angle, nothing goes to the cod-end.
  • Indicates if your grid is blocked.
  • Estimate fish volume in the codend as the grid angle tends to increase with volume.

Grid Angle

Wingend Spread
Provides the distance between the wingends.

  • Keeping the optimal wing spread can be just as important as doorspread.
  • Wingspread is a critical piece of information for researchers in calculating swept area

Wingspread

Trawl Alignment
Indicates the alignment behind the doors.

  • Calculates the distance from the starb door to the headline and from the port door to the headline.
  • Indicates the adjustment in side current and when turning.
  • Trawl angles are also calculated to ensure gear has correct hearding effect.

Trawl Alignment