The two helicopters were both tasked to fly to the scene, west of Kingaroy, at around 2.30pm.
Both landed in a clear area, close to the crash site.
Queensland Ambulance Service (QAS) paramedics were already at work, along with Queensland Fire and Emergency Service officers, when the choppers arrived.
The driver of the car reportedly swerved to avoid a kangaroo.
The vehicle rolled and burst into flames, causing an area of roadside bush land to catch fire.
An RACQ LifeFlight Rescue QAS Flight paramedic, a LifeFlight Rescue Flight Nurse and a LifeFlight Critical Care Doctor, assisted QAS road crew paramedics, in assessing and treating multiple patients.
The Brisbane-based RACQ LifeFlight Rescue helicopter airlifted a child, in a critical condition, to the Queensland Children’s Hospital.
A man, aged in his twenties, was also in a critical condition, when he was airlifted to the Royal Brisbane and Women’s Hospital, by the Bundaberg-based RACQ LifeFlight Rescue helicopter.