The car appears to have become airborne after hitting a raised roadside berm at the western end of Harts Rd.
The car has been launched across Southbridge Sedgemere Rd before it smashed through a farm fence and into a macrocarpa hedge, narrowly missing a concrete power pole. Police say investigations into the crash are ongoing.
Police today named the three 15-year-old victims who died in the crash near Leeston, southwest of Christchurch, just after 2am yesterday morning, as Cole Troy Hull, Samuel James Drost and Lily Frances Moore.
A 14-year-old boy was behind the wheel and he remains in hospital with serious injuries. Another 14-year-old, the only occupant wearing a seatbelt, suffered minor injuries and was discharged from hospital yesterday.
The three dead teenagers attended different high schools: Hull at Ellesmere College, Drost at Lincoln High School, and Moore at Rangi Ruru Girls' School in Christchurch.
Ellesmere College principal Gavin Kidd told Fairfax the school community was "deeply saddened" by the tragedy and the school was offering support to students and parents.
"All of our students are important and losing one is a tragedy. Our thoughts and sympathy go out to Cole Hull's family and the other victims.
"The school will be doing all we can to support the families involved and all of our students and staff affected."
Three teachers would be at the school today to support the local community if needed and the tragedy would have a huge effect on students.
Rangi Ruru principal Dr Sandra Hastie said in a statement provided to the Herald news of Lily Moore's death had been met with "immense sadness" at the school.
"Our heartfelt condolences go to Lily's family and friends.
"Rangi Ruru is a strong, closely-knit and supportive community and as such, we of course have reached out to the grieving family so they know we are here for them at this difficult time."