retained largely because the line, built for 1920s streetcars, would have to be substantially rebuilt to accommodate the heavier modern cars used on the Green Line. In order to clear the line of snow, the MBTA maintains a jet engine-powered snowblower, officially the Portec RMC Hurricane Jet Snow Blower, model RP-3, dubbed "Snowzilla". Snowzilla weighs , measures 8 by 12 by 27 feet, and is powered by a Westinghouse J34 turbojet engine. It uses approximately of jet fuel per line clearing run. Other T lines simply run regular trains to clear the tracks of snow, but the PCC cars' traction motors would short out if they were used for that purpose. The current set of PCC cars are "Wartime" PCCs, built by Pullman-Standard in 1945–46. They have been in continuous revenue service in Boston since their construction, although PCC cars were not assigned to the Mattapan Line until 1955. The current fleet was rebuilt as part of a systemwide PCC rebuild program in 1978–83, and again in 1999-2005. During the latter rebuild, the cars were repainted from their former Green Line paint scheme to a brighter orange and cream design, similar to their original coloring. The cars also carry a unique geographic MBTA logo, reminiscent of the old Metropolitan Transit Authority map logo found on the cars between 1948 and 1955. On several occasions, the MBTA has proposed to replace the PCC streetcars either with newer trolleys or with buses, and has met with substantial community opposition on each occasion. The FY2017-FY2021 Capital Investment Plan, approved by the MassDOT board in June 2016, allocated $9 million to the line including $3.7 million for maintaining the PCC cars. The plan also allocates $5 million for "PCC Car Replacement-Alternative Service" which will be used for future funding should an alternate form of transportation be decided upon. In 2017, MBTA began a $7.9 million project to overhaul the trolleys and update the propulsion systems, but further problems such as fluctuations in power damaged the four operating trains in early 2018. On February 5, 2018, it was reported that eight more trolleys were going to re-enter service in 2019, the fixes will prolong the lifespan of the trains by another 7 to 8 years. After several delays, the first rebuilt trolley entered service in March 2022. The MBTA also announced in 2018 that it was studying alternatives again to running trolleys. Alternatives that were