Class 1201/Gruppo 420 (Locobase 3669)

Data from Ugo Poddine as contributor to Bryan Attewell ([] Steam locomotive simulator (April 2000). Additional data from the US Military Railway Service's Equipment Data Book for Italian Locomotives supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. For class details and axle loading, [] (visited 30 June 2005). See also Ferrovie Dell' Alta Italia, Album Delle Locomotive (Torino, 1o Luglio 1876), T54. Wikipedia's "Locomotiva FS 420", at [], last accessed 19 August 2019.

These were built in Germany and Italy from 1872 to 1904. The first engines were produced by Wiener Neustadt. Later batches came from a variety of builders including Maffei of Bavaria, Ansaldo, Breda. Wikipedia commented that the design's good qualities derived from its simplicity in construction, adding "fattore non trascurabile ai fini dell'economicita e della manutenzione di una locomotiva a vapore (Google translates as "a not insignificant factor for the purposes of economy and maintenance of a steam locomotive". Amen.)

Poddine notes they ran over such mountain routes as the Porrettana and Giovi lines when the compound-expansion Grupo 470s were introduced in 1907. The class was credited by the MRS with 15,520 lb of steam per hour and rated at 620 hp at 18 mph. In later batches, the maximum axle loading rose to 14,300 kg (31,526 lb) and total weight to 57,300 kg (122,797 lb).

Locobase found inconsistencies between the given values for the tube diameters, tube lengths, and for the evaporative heating surface area given as 158.0 sq m. The EHS value shown in Locobase's specs is composed of the firebox heating surface area given in the diagram and the tube heating surface area calculated from the stated tube length, external tube diameter, and count.

Class Gruppo 895 (Locobase 6624)

Data from the US Military Railway Service's Equipment Data Book for Italian Locomotives supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

According to [], the first series numbered 8951 to 8980 and 89531 to 89542, (42 locomotives); these were delivered in 1908-1910. The second series -- n 89601 to 89665 -- were built in 1910-1914. It's not clear to Locobase whether the last 10 were not completed.

It was credited by the MRS with 11,660 lb of steam per hour and rated at 510 hp at 18 mph.

Locobase 3688 shows the superheated variant.

Class Gruppo 896 (Locobase 3688)

Data from Ugo Poddine as contributor to Bryan Attewell ([] Steam locomotive simulator (April 2000). Additional data from the US Military Railway Service's Equipment Data Book for Italian Locomotives supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Like many Italian designs, these low-drivered switchers -- modified Gr 895s -- had plenty of superheat. Although unusual for switchers, such a high degree of superheated probably allowed for smaller bunkers for coal and water. This design had other rare qualities for a European locomotive. There were many more flues than tubes and the cylinders were "over-square". It was credited by the MRS with 11,000 lb of steam per hour and rated at 610 hp at 18 mph, 100 hp more than the saturated-steam 895.

Class unknown (Locobase 8946)

Data from Albert H Bone, "Some Recent Designs of Locomotives for Service on Continental Railways", Cassier's Magazine, 1910, pp. 561-609.

Bone describes this locomotive as a powerful narrow-gauge engine. The accompanying photo shows a classically German all-adhesion design.