The BDŽ class 75 is a series of Bulgarian

narrow-gauge A narrow-gauge railway (narrow-gauge railroad in the US) is a railway with a track gauge (distance between the rails) narrower than . Most narrow-gauge railways are between and . Since narrow-gauge railways are usually built with tighter curv ...

diesel-hydraulic locomotive A diesel locomotive is a type of railway locomotive in which the power source is a diesel engine. Several types of diesel locomotives have been developed, differing mainly in the means by which mechanical power is conveyed to the driving whee ...

s. The first 760 mm track-side diesel locomotives of the BDŽ were built by the German company

Henschel & Sohn Henschel & Son () was a German company, located in Kassel, best known during the 20th century as a maker of transportation equipment, including locomotives, trucks, buses and trolleybuses, and armoured fighting vehicles and weapons. Georg Ch ...

Kassel Kassel (; in Germany, spelled Cassel until 1926) is a city on the Fulda River in North Hesse, northern Hesse, in Central Germany (geography), central Germany. It is the administrative seat of the Regierungsbezirk Kassel (region), Kassel and the d ...

, and were put into operation in

Bulgaria Bulgaria, officially the Republic of Bulgaria, is a country in Southeast Europe. It is situated on the eastern portion of the Balkans directly south of the Danube river and west of the Black Sea. Bulgaria is bordered by Greece and Turkey t ...

in the beginning of 1966. As soon as they arrived, they became the main narrow-gauge locomotive series at the

Septemvri Septemvri (, , ) is a town in Pazardzhik Province, southern Bulgaria. It is the administrative center of homonymous Septemvri Municipality. As of 2024 the town had a population of 8,071. Geography The town is situated at an altitude of about ...

depot, took the passenger (from the series 81 and 82) and the freight (from the 600.76 series locomotives) service on the railway lines Septemvri - Dobrinishte and -

Pazardzhik Pazardzhik ( ) is a city situated along the banks of the Maritsa river, southern Bulgaria. It is the centre of Pazardzhik Province and Pazardzhik Municipality. It is located in the Upper Thracian Plain and in the Pazardzhik-Plovdiv Field, a ...

. Moreover, due to the higher power of the locomotives, the trip from Septemvri to

Dobrinishte Dobrinishte ( ) is a small town and ski resort in the Blagoevgrad Province, Bansko Municipality, southwestern Bulgaria. it had 2973 inhabitants. It is located 6 km east of Bansko, a famous winter resort. It has an altitude of 850 m and is ...

was shortened by more than 1 hour. The locomotives were constructed under the technical conditions of BDŽ and consisted mainly of: a diesel engine with a power of 1100 hp, a hydraulic gear and the wheelset formula is B'B'. When built in the 1960s, they were the most powerful 760 mm gauge diesel locomotives in the world. They were also the first time Bulgarian locomotives used the cavities in the main locomotive frame for fuel storage. The first locomotive to be scrapped was 75 007.5, which derailed on January 16, 1991 due to a broken track on the open line to "Dryanov Dol". The damage could have been repaired, but due to a locomotive surplus it was made into a spare parts "donor" for the other locomotives and was eventually scrapped in 1994.

Factory data and status

References

{{Reflist 760 mm gauge locomotives Narrow-gauge locomotives of Bulgaria B-B locomotives Henschel locomotives Railway locomotives introduced in 1965