The tugs are constructed to a typical Japanese ASD design and measure 36m in length overall, with a beam of 9.8m and draft of 3.4m. The main engines are Niigata 6128HX diesels running at 750rpm to deliver a total of 4,200 bhp.

Coupled to Niigata ZP-31 propulsion units, this arrangement gives the tugs a bollard pull of over 60 tons and a top speed of 14.5 knots.

Both tugs are equipped for shiphandling over the bow in the push-pull mode with winches by Masada and are well fendered for this close quarters work. Kinnaird also has an after winch for towing astern and a useful deck crane. Fire fighting equipment is installed in both vessels with two remotely operated monitors, one on the mast and one above the wheelhouse rook, delivering a total of 8,000 litres of water per minute.

This Scottish subsidiary of the J P Knight Group, based at Chatham in Kent, is no stranger to Japanese tug technology. It was into this fleet that the company introduced the first Japanese ASD shiphandling tug in the UK and Europe in 1981.

Named Kinross, the vessel remains in the Invergordon fleet, and a comparison with the two modern acquisitions gives an interesting illustration of genuine evolution.

Most of the features popular in this type of tug have been retained, yet the power and performance has been enhanced to meet the needs of larger ships. The slow running Niigata main engines are particularly popular among owners familiar with the breed.

J P Knight (Caledonian) Ltd are well established in the Cromarty Firth providing shiphandling duties at Invergordon and Nigg, and a wide range of towage and other services to the rigs and other floating plant from the offshore oil and gas industry. Kincardine and Kinnaird have joined the purpose built ASD tug Kincraig and the older Kinross to carry out this work as well as coastal towing and contract work all around the coastline of the UK and north west Europe. The Kincraig, an ASD of 50 tons bollard pull, was built in 1998 and has proved to be highly popular.