then a light 4–6-mm ground chain. Doing so might still have fewer impacts and less drag than a single 8- or 10-mm chain. The key to such a configuration operating effectively relies on a sufficiently weighted (semi-pelagic) foot rope at an optimal distance off the substratum. Compared to the 10-mm chain, simply choosing 6- or 8-mm would reduce drag by up to 7% for the assessed beam trawl.The differences for an otter trawl would be less noticeable owing to the contribution of drag by the otter boards, but would still rep-resent ∼5% drag reduction for the 6-mm ground chain in an otter trawl system that had 20% more drag than the beam-trawl system.Obviously, the ultimate utility of any such configurations would need to be validated using conventional trawls and across the full range of conditions (including different substrate types, depths and weather).As fuel prices and concerns over habitat damage (and/or escape mortality under foot ropes) increase, it will become more important to assess the impacts and operational characteristics of ground gears used with penaeid trawls. This has previously (largely) been avoided due to the complexity and technical challenges associated with the required experiments. Nevertheless, quantifying the mechanics and importance of ground gears in terms of the engineering and catching efficiencies of penaeid trawl systems(possibly following similar methodologies as that presented here)will help to progress environmentally sound configurations.