Double-deck car transportation wagon, type DDm

In order to carry out car transportation along with the passengers, after a few prototypes built during the 50s and achieved by modifying closed wagons and the following construction of special closed wagons with double axis, equipped with downward tilting doors at each end which enable car loading, towards the end of the 60s, following different transport needs and in answer to growing requirements in capacity and higher velocity, the Italian State Railway FS ordered 13 off car transportation wagons series Sekqrs (serial no 31 83 438 4 000 ¸ 112); these wagons were purpose built in order to complement the long haul overnight services. They were double decked and could transport an average of 12 off cars and were equipped with bogies type 24C which allowed them to have travelling speeds of up to 140 Km/h. These wagons were characterized by the loading mobile ramps at each extremity, which allowed the cars to be loaded on both decks, and by the slate grey livery with first type 70s FS logo. Moreover these wagons were equipped both with steam (still in use at that time) and electric heating channelling that connects locomotives to passenger coaches.

After this initial series, FS ordered another one that has 50 off units (serial no 31 83 438 4 013 ¸ 062) with exactly the same features as the previous series but without the steam heating channelling.

Double-deck car DDm 3rd series

During the mid 70s a third series was ordered; this again with 50 off units (serial no 31 83 438 4 063 ¸ 112), but this time with a structural design change that meant the fixed loading ramps at each extremity, thanks to the new loading system built at each train stations where these vehicles were loaded, and with a few esthetical changes and a slight increase of weight; all the remaining characteristics remain unchanged from previous series.

The classification of the Sekqrs wagons, in International service, was firstly doubled (road identification number as vehicles series DDm classified as a coach, and as a wagon) and afterwards unified as vehicle; the Sekqrs vehicles were definitively classified as DDm, with road series number 51 83 98-40 000¸ 012for the first series and 51 83 98-30 013¸ 112for the second and third series. Further to this classification, the loading mobile ramps, typical of the first and second series, were fixed in the upper position.

Double-deck car DDm 4th series

In 1984 to the 113 off car transportation units were integrated with a further 56 units (serial no 51 83 98-30 113¸168) with a few minor improvements from previous series: firstly with a change in bogies to swan neck shaped FIAT design (similar to those used for Middle Distance Coaches but equipped with block brake system in the stead of disk brake), and without the steam heating channelling (serial number with code 30 in place of 40) as in the two previous series and with safer designed handrails.

The colouring scheme of these last series followed the livery that was in use at that time, namely beige grey with dark red streaks. In more recent times some of these wagons have been painted in medium grey (the same colour used for the window streak of the UIC Z coaches with livery in two different shades of grey) with FS 80s logo and numbering and coding in yellow. The largest part of the wagon DDm still with the outdated slate grey livery were either repainted with the new colour scheme or at least the logo changed to FS 80s styled in ivory. Up to date none of the wagons DDm have been painted according to the new XMPR livery in light grey, green and light blue, adopted by the new FS Corporate Identity. Nowadays all the wagons equipped with FIAT bogies are allowed to travel up to a speed of 160 Km/h, with relevant serial number modification.