The Mumbai—Ahmedabad High Speed Rail (MAHSR) Project is the first High Speed Rail (HSR) network planned to be constructed in India. The MAHSR Project line connects Mumbai, located in Maharashtra State with Ahmedabad in Gujarat State, passing through one Union Territory. India’s efforts to build high-speed rail (HSR) networks are a major step in the right direction towards updating its transportation system. This abstract explores how using the precast fabricated Full Span Girder play an important role in the construction of HSR. This paper investigates how high-speed rail systems are built and operated by using the advanced technology of Full Span Girder construction in construction industry. Not only casting of such a length girder is challenging as well as managing, transporting and launching is a big task to complete. To understand this brief description of equipment’s and their working is also mentioned in paper. On such challenging work this paper presents importance launching process of full span girder in HSR construction in a simple way along compared it with traditional launching method i.e. Span by Span (SBS) technique and shows the subsequent decrease in time cycle of launching. Primavera-P6 software is used to calculate the cycle time of full span girder launching technique. Monte Carlo simulation performed to incorporate uncertainties too into the process of full span girder launching to see the maximum delay that could happen when things will not as it planned. Future scope is varied vast as it is emerging technology in field of viaduct construction.