In order to improve the operation of steam locomotives on winding mountain lines, the T 16 with the number “Erfurt 1980” was developed for trial use on the mountain lines in the Thuringian Forest. Its distinctive feature was a second cab at the front to improve visibility of the track. It was not mass-produced and should therefore not be confused with the later freight locomotive T 16 with 0-10-0T wheel arrangement.
A symmetrical chassis with the wheel arrangement 4-6-4T and 1,750 mm large driving wheels was used as a basis to enable a speed of 90 km/h in both directions. The requirements stipulated that these locomotives should be able to pull 200-tonne trains at top speed on level ground and up one percent steep gradients at 75 km/h or 47 mph. As with the two S 9 trial locomotives that were built at the same time, a third man was deployed in the front cab to support the driver. There was a voice connection between the cabs in order to be able to give the appropriate instructions based on the observations on the line. In contrast to the S 9, the front was not tapered due to the lower speeds.
With its extremely generously dimensioned grate area and the equally large evaporative heating surface, the locomotive was able to achieve a high level of continuous output. However, the complex operation with the two cabs was not convincing and therefore there was only one example, which was only used sporadically. A real successor was the T 18 from 1912 with the same wheel arrangement, which was conventionally equipped with only one cab and was still able to provide sufficient performance with a simple engine.