technical department and starting in March 1939 as head. Five Luxtorpedas were constructed under his leadership, which were able to reach a speed of 115 km/h. He was involved with the construction, production and test-runs of locomotives in particular those destined for export to Bulgaria, Morocco, Lithuania and Soviet Union. Due to his knowledge of foreign languages he was repeatedly sent abroad for business purposes pertaining technical aspects and co-operation. During the Nazi occupation of Poland, Fablok was incorporated into Henschel & Son under the name Oberschlesische Lokomotivwerke Krenau. Sielecki worked as a technologist. In this time, with the consent of the general director Guido Sanchez de la Cerda, he was involved in protecting his Jewish co-workers from Nazi persecution. Together with his colleagues from the technical bureau he started hiding the technical documentation for steam, industrial diesel and electrical locomotives and moved them completely out of the plant in January 1945, since the Nazis wanted them destroyed. After Poland was liberated, this documentation proved vital for the re-construction efforts of the national railway industry, especially the diesel and electrical locomotives. This allowed Fablok to restart the production of these types. In the post-war years, he was technical director until 1964. Under his leadership, the production was re-established for multiple types of locomotives, 12 of that type were destined for export. From 1945-61 he accompanied delegations of the ministry heavy industry and foreign trade of on various occasions to trips abroad. From 1965, he was technical advisor to the board until his retirement on March 31, 1971. In the 1960s and 70's, he also lectured at the Cracow University of Technology and technical school in Chrzanów. He died of a sudden heart failure while vacationing with his family. He was laid to rest in the family tomb in Rakowicki Cemetery in Kraków. Works He published various essays on technological subjects, his first one appeared 1932 in the Fablok publication for the 500th locomotive produced, as well as six folios for the 50-year anniversary of Fablok 1924–1974. He translated various technical literature and books from German into Polish. He was also very active in the Kraków chapter of the Polish Federation of Engineering Associations (NOT). He was co-founder 1937 in Fablok of the Polish Society of Mechanical Engineers and Technicians (SIMP) and was head of the Fablok chapter for many years. Together with engineer Zdzisław Wład he developed a patent for