Trans-Andes Railway No. 9 and 11

As an alternative to the eight class Z Kitson-Meyer rack locomotives, Maschinenfabrik Esslingen supplied these two locomotives. They had a front bogie with three carrying axles and three rack pinions for the Abt system. The rear bogie had four coupled axles for the adhesion drive. Initially, a condensation device was installed, which was soon removed.

They were numbered 9 and 11 from the factory, 9 was soon renumbered to 10. Number 10 derailed in the mountains between Juncal and Portillo in 1910. Although it slid down the mountainside with eight cars, it could be recovered and put back into service. Number 11 was wrecked in an avalanche in the twenties, but in this case it had to be written off.