The LM15 provides a square, amber coloured optical display on which a vertical black line indicates the centre line of the approach. Off the centre line, this black vertical bends to form an arrow, indicating the direction to steer in order to regain the centre line.

The arrow pattern provides continuous instant and accurate indication as soon as a vessel drifts off centre. If the drift continues, it becomes increasingly 'angry looking' as more arrows are seen, and these pattern changes can be used to monitor the rate of drift off and back on to the centre line. In addition, the angles off centre, when the first and second arrows touch the edge of the display, can be calculated to provide 'clearing' lines to indicate the proximity of hazards. In this instance, the first arrow position on each side of the centreline is configured to give pilots a very accurate and final warning that the side of the ship could be within 5m of the relevant hazard.

With the biggest lock in the UK, Royal Portbury Dock is perhaps the easiest British port for large ocean-going ships to enter and the LM15 makes it possible for these ships to be manoeuvred safely into the new berth. A new £16m forestry products terminal, an £80m bulk handling terminal and a rail link with multi-purpose facilities have recently been completed.

The Inogon LM series is manufactured by FMT in Trelleborg, Sweden, a company which also manufactures passenger boarding bridges for cruise ships and ferries. The moire principle of the Inogon LM is also used in specialist guidance devices supplied by FMT for airports.

MJ Information No: 18622