The South African Railways Class 16DA 4-6-2 of 1928 was a steam locomotive. In 1928, the South African Railways placed six Class 16DA steam locomotives with a 4-6-2 Pacific type wheel arrangement in passenger train service. Eight more entered service in 1929. Manufacturers Further orders for locomotives similar to the Class 16D Pacific type locomotive were placed for the South African Railways (SAR) in 1928. The design of the earlier engines was modified by the Chief Mechanical Engineer (CME), Colonel F.R. Collins DSO, along the same lines as his design of the Class 15CA Mountain type. This consisted of a locomotive bar frame which was shorter to end at the front of the firebox, with a bridle casting to create a widened frame extension below the firebox and the cab to the rear dragbox to gain more ashpan room under the firebox. These redesigned locomotives were designated Class 16DA and were built by two manufacturers in 1928 and 1929. The first six, numbered in the range from 868 to 873, were built in Germany by Hohenzollern Locomotive Works and entered service in 1928. Another eight locomotives, numbered in the range from 843 to 850, were built in the United States of America by Baldwin Locomotive Works and entered service in 1929. Characteristics The Hohenzollern and Baldwin-built Class 16DA locomotives basically differed from the predecessor Class 16D only by virtue of its shortened frame and bridle casting, the Class 16D having had a frame extending all the way from the front buffer beam to the rear dragbox. They used the same Type KT tenders with a coal capacity of and a water capacity of . As delivered, they had diameter coupled wheels and their cylinders were of bore and stroke. Their boiler operating pressure was set at . Modification During the 1940s six of these locomotives, three from each manufacturer group, were retyred with diameter tyres on their coupled wheels. To not have their tractive effort reduced by the larger coupled wheels, their cylinders were reamed from a bore of and their operating boiler pressure was raised to . All the modified locomotives remained classified as Class 16DA. When the larger tyres were fitted, the old tyres were left in position and turned down on the wheel centres to serve as liners and the new tyres were then shrunk on over the liners. The practice of increasing the diameter of coupled