1981: First tests with electronically-controlled fuel injection on a Sulzer low-speed engine, using individual, hydraulically-operated fuel injection pumps.
1990 Mar: World’s first multi-cylinder electronically controlled uniflow two-stroke engine is started on the Winterthur test bed. Tested until 1995.
1993: Project started to develop the Sulze RT-fl ex common- rail system.
1996: Component testing began for the Sulzer RT-flex common-rail system.
1998 Jun: Starting of the first Sulzer RT-flex fullscale engine on the Winterthur test bed. Sulzer 4RTA58T-B research engine.
2000 Feb: Order for the first series-built Sulzer RT-flex engine.
2001 Jan: Official shop test of the first series-built Sulzer RT-fl ex engine, the 6RT-fl ex58T-B at Hyundai H.I. in Korea.
2001 Sep: First RT-flex engine entered service. Sea trials of the bulk carrier Gypsum Centennial with a Sulzer 6RT-fl ex58T-B engine, of 11,275 kW.
2002 Oct: Official shop test of the first Sulzer RT-fl ex60C engine, at Wartsila's Trieste factory in Italy.
2003 Jan: Official shop test of Sulzer 7RT-fl ex60C at Hyundai H.I. in Korea.
2003 Jan: Sulzer RT-flex96C and RT-flex84T-D engine types announced.
2003 Mar: Sulzer RT-flex50 engine type announced.
2003 Mar: Official shop test of first Japanese-built RT-flex engine, a Sulzer 6RT-fl ex58T-B at Diesel United Ltd.
2003 Aug: Aframax tanker Sea Lady entered service in Japan with Sulzer 6RT-fl ex58T-B
2003 Nov: Multi-purpose carrier Wladyslaw Orkan entered service in China with Sulzer 7RT-fl ex60C.
2003 Nov: Reefer Carmel Ecofresh entered service in Portugal with Sulzer 7RT-fl ex60C.
2004 Jan: Sulzer RT-fl ex68T-B engine type announced.
2004 Feb: Multi-purpose carrier Chipolbrok Sun entered service in China with Sulzer 7RT-fl ex60C.
2004 Feb: Reefer Carmel Bio-Top entered service in Portugal with Sulzer 7RT-fl ex60C.
2004 Mar: Confirmed orders for RT-flex engines reach 100.
2004 Apr: Official shop test of first RT-flex96C engine, an 8RT-flex 96C at HSD Engine Co Ltd in Korea.
2004 May: Multi-purpose carrier Chipolbrok Moon entered service in China with Sulzer 7RT-fl ex60C.
2004 May: Containership Safmarine Cameroun entered service in Germany with Sulzer 9RT-fl ex60C.
2004 Jun: Official shop test of world’s largest common-rail engine, a Sulzer 12RT-fl ex96C engine of 68,640 kW at Diesel United Ltd in Japan.