Complex sentence: In 1988,2 years prior to accident, the cable car went under major reconstruction with the head engineer Vakhtang Lejava, originally cable car used 3 supporting towers replacing the 20 meter high lower mast with a new 25 meters high mast.
Split into simpler sentences: In 1988,2 years prior to accident, the cable car went under major reconstruction with the head engineer Vakhtang Lejava, originally cable car used 3 supporting towers. Redesigning meant replacing the 20 meter high lower mast with a new 25 meters high mast.