Case Study: Robert Allan Ltd achieves high-power tug performance with Cummins QSK95 engines

Cummins Powered RAstar 3500 with 8400 HP

Robert Allan Ltd, a naval architect firm known for tug and vessel designs, wanted to demonstrate the versatility of Cummins’ new QSK95 marine diesel engine in a high-power escort tug application. The challenge was to create a proven RAstar 3500 design that could effectively use the engines in demanding shiphandling and offshore terminal operations.

Cummins worked with Robert Allan Ltd to adapt the RAstar 3500 tug around a pair of QSK95 engines, each delivering 4,200 BHP, for a combined 8,400 HP. In testing, the design achieved 102 tonnes of bollard pull ahead, 96 tonnes astern, and an estimated 14.2-knot free-running speed, showing that Cummins’ Tier II-compliant engines could deliver strong performance in a large escort tug package.

Robert Allan Ltd