Konstal 114Na

The 114Na is a three-section, unidirectional, single-sided tram with 13% low floor accessibility. Compared to its predecessor, an additional section was added, and the low-floor section was placed in the middle compartment. This allows wheelchair users (with the assistance of another person) and strollers to enter.^[5][1] Despite similarities, the body structure was made using a different technology than the Konstal 105Na model. The body is made of closed profiles and represents a structural development of the Konstal 112N tram. The connection between the sections is made using double articulation, previously unused in Poland, allowing for quick uncoupling and coupling of the mechanical and electrical parts.^[1]

The floor is made of plywood-rubber panels and covered with anti-slip flooring. The flooring is smooth and folded onto the walls to facilitate interior cleaning.^[1] The tram is equipped with five doors, each 1,300 mm wide, folding outwards, secured with a triple system to prevent passengers from being caught (sensitive edges, phototube, overload switch). The doors can be opened centrally by the driver and by passengers using buttons.^[1]

The tram features exclusively single seats, mostly facing forward. The seats were specially designed for this vehicle and were among the most modern seats used worldwide at the time of production. They are vandal-resistant yet covered with elegant fabric.^[1] One of the tram's advantages is its large capacity, able to accommodate a total of 285 passengers.^[2] This is more than two times the capacity of the 105Na and slightly less than three times the capacity of the 105Na.^[4]

The tram is equipped with forced air heating. There are no ventilation or air conditioning devices inside the carriage; only natural ventilation is possible through tilting windows and roof hatches.^[1]

The 114Na is equipped with fluorescent lights illuminating the interior of the body as well as additional lights illuminating the doors.^[1]

A thyristor-based traction control system is employed, capable of energy recuperation during braking. The entire system is mounted on four traction bogies.^[1]

The tram is equipped with a control panel allowing for maneuvering at a speed of 10 km/h.^[1]

Country	City	Year of delivery	Number	Rolling stock number
Poland	Gdańsk	1997	2	1501-1502	[9][10]
Total number:			2

21/22 March 1997 marked the delivery of the first tram to Gdańsk,^[9] followed by the second in April.^[10] They were assigned serial numbers 1501 and 1502, respectively, and were directed to the Wrzeszcz depot to serve on line no. 12. Initially, due to numerous breakdowns, the trams spent more time in the depot than on the tracks.^[7] Thanks to the arrival of these vehicles, plans to build the line to Chełm were resumed. However, an expert analysis conducted at the Gdańsk University of Technology revealed that the 114Na trams, like all others in service at the time, were not suitable for operating on such a line profile.^[11] In 1999, Gdańsk purchased additional trams tailored to the needs of disabled people – the Konstal NGd99, which could safely operate on this line.^[11]

During the initial period of operation, these trams were characterized by a high incidence of electrical system failures,^[2] which prompted a modernization by the Municipal Transport Company in Łódź [pl] in 2000.^[12] It was decided to replace the IGBT transistors with GTO thyristors, which had proven successful in the 105N2k and 116N models.^[2] In the following years, the incidence of failures decreased, although it was not eliminated.^[13] During this overhaul, the trams were repainted in colors different from the standard Gdańsk livery.^[12]

On 10 January 2002, tram no. 1501 was involved in a minor collision. The tram stopped at Błędnik Street [pl], then rolled into an NGd99 tram. As a result of the collision, the bumper of the 114Na was slightly damaged.^[14]

In 2008, tram no. 1502 was taken out of service for repairs. The downtime lasted 4 years and was accompanied by a minor modernization. Seats were replaced, and the livery was changed to something more akin to the colors used on Gdańsk buses. A similar scope of repairs was carried out on the second tram at the Wrzeszcz depot.^[15]

Due to an extensive overhaul at their own facilities, tram 1501 was sent for major repairs to Modertrans in February 2012. During this repair, the tram received front panels similar to those used in the Moderus Beta MF 01, sandboxes were built, seats were replaced, and LED displays were installed. Despite these upgrades, the vehicle cannot operate on the Chełm line due to insufficient power.^[16] After the modernization, the tram was designated as 114Na – MF 12.^[17] In March 2016, Gdańsk Municipal Transport Company announced a tender for the modernization of the second tram,^[18] similar in scope to the one carried out in 2012 by Modertrans.^[19] In early July, Modertrans won the tender as the sole bidder.^[20] The refurbished tram returned to Gdańsk in late July and early August. During the overhaul, the focus was on the interior and electronics, aiming to preserve as much of the original appearance as possible, as the carrier plans for the tram to become a historic vehicle in the future.^[21]

In December 2015, tram no. 1501 was named after the Polish writer Stanisława Przybyszewska.^[22]