The GE Transportation C44aci is a model of Australian heavy duty diesel electric locomotive designed by UGL Rail and built at their Broadmeadow factory.

The C44aci(initially designated as C43aci) was designed by UGL Rail in response to a tender issued by Pacific National, who required a locomotive to match the performance of their existing 90 class units when hauling heavy coal traffic, while still having the ability to work high speed intermodal services, with the change between applications to be simple.

This design did not meet the requirements for Pacific National due to the heavy axle load, acceptable on the heavily laid coal routes, but not on lines outside of the Hunter Valley.

Simulation work showed that three C44aci locomotives could equal the performance of 90 class units in heavy mode, while in intermodal mode could outperform the older NR class units by 20% on services, with the same sectional running times and in some areas a slight reduction in fuel consumed due to the increased adhesion resulting from AC traction.

[1] However the 4400BHP C44aci was outperformed by the competitors 4500BHP GT46C-ACe locomotive produced by Downer EDi Rail in back-to-back trials performed by RailCorp on the steeply graded Cowan Bank.

[5] All 15 units entered service on coal trains in the Hunter Region and were trialed on Brisbane—Melbourne freights and return.

[6][7] In 2012 Pacific National took delivery of six 93 class C44aci locomotives optimised for intermodal freight transport between Melbourne and Brisbane.

9403 was in the final stages of painting and pre-delivery in May 2024 sitting alongside the new CF4428 and ACD6056, with a noticeable difference in cab shape above the windscreen and below the horns.

In July 2008, QR National subsidiary Australian Railroad Group ordered eight locomotives, with options for 16 more units.

[16] These units feature updated electronic control and engine management systems, and had their entry to service delayed by weight issues, with steel body side doors being replaced with lighter aluminium substitutes.

[20] These units were to be fitted with electronically controlled pneumatic braking equipment, for operation with similarly Hunter Valley Coal wagons.

[17][21] QR National subsequently ordered an additional 12 locomotives to operate intermodal trains.

In 2012 and in 2020, Genesee & Wyoming Australia took delivery of 11 locomotives for use on Hunter Valley Coal trains services, numbered GWU001-GWU011.

They along with two units completed for but not delivered to Genesee & Wyoming Australia were sold to Mineral Resources as the MRL class.

The first entered service in June 2014 hauling iron ore train from Mount Walton to Kwinana.

[29][30] Qube announced the purchase of an unspecified number of locomotives in March 2020, for delivery over 18 months.