Three Warp Twin Rig - Shortening the Centre Warp

Alternative names

  • twin rig, centre warp, twin rig trawling, three warp, shorten

Information sheets providing figures to advise skippers towing three warp twin rig trawl gear how much to shorten the centre warp by to keep the gear square. By this we mean, to ensure that the two trawl doors and centre clump weight are in line and the gear should be being towed square. This fact sheet should be used in conjunction with other fact sheets on setting up twin rig trawling and measuring door spread and calculating sweep angle and wing end spread.

The charts below are suitable for vessels using a warp length between 75  fathom and 425 fathom, with a total door spread between 20ft and 620ft.

There are several different charts below. The first figures ''warp 75 - 300'' indicate the range of warp lengths, the second part ''door spread 200 - 500ft'' indicate the range of overall door spread  covered by that chart.

Chose whichever chart covers the ranges that you usually work your gear in.

These charts suit vessels using 3 wire warps of all the same diameter. If using heavier warp in the centre or dyneema warps the calculations may vary considerable due to differences in the catenary of the wraps.

Other charts are available to suit a range of  other gear set ups, if these do not suit your vessel bespoke charts can be produced by contacting Seafish. Charts are also available with door spread in fathoms  and with all dimensions in metres.

An illustration of a vessel towing a three warp twin rig using a three wire set up with two trawl doors and a central clump
An aerial view of a vessel towing a three warp twin rig