The invention is a device to hold a trawl net open and make it press against the sea bottom. The device consists of a horizontal foot bar (8) to which is attached a vertical wing (10) to create a lateral pulling force on the trawl net. At right angles to the vertical wing (10), a horizontal wing (11) is attached to create a downward vertical force. Both wings are shaped like aircraft wings to utilize hydrodynamic principles for the creation of the above-mentioned forces when the device is being towed in the water. Alternative embodiments may include a device with an aircraft wing profile attached to the vertical wing (10) and a body shaped like a quarter of an egg, the rounded part of which is facing downwards, said body also attached to the vertical wing (10). In the leading edge of the foot bar (8) is a fastening loop (9) for the towing warp (3) coming from the trawler, while in the trailing edge of the foot bar (8) is a bottom warp fastening loop (12), and a top warp fastening loop (13) on the vertical wing. The horizontal wing (11) may be hinged to the vertical wing (10) to allow for vertical movement. A profiled body may also be hinged to the vertical wing (10). The horizontal wing (11) or the egg-shaped body can both be manoeuvred by means of a pneumatic system.