Rollover Test





The following page provides information and a range of photos of the1991 Ambulance rollover test conducted by the Metropolitan Ambulance Service



In April 1988, a moderate speed ambulance accident in Melbourne's Elizabeth St saw the complete collapse of the rear compartment of the Ambulance entrapping one of the Officers. It was discovered on investigation that the design of the fibreglass rear module failed to provide any structural strength in a rollover or side impact, putting Officers and patients at significant risk of injury. The investigation also discovered fatigue cracks in the framework of a number of vehicles placing further concerns to staff.

As a direct result of investigation, Transport Industry Consultants (TIC), a private company, was employed by the Metropolitan Ambulance Service (MAS) to evaluate Ambulances built during the 1980’s. As a result of TIC’s investigation, speed restrictions were placed on all such vehicles due the potential danger to staff and patients. On the recommendations of TIC, a committee was also formed including representatives of the Victorian Health Department, Ambulance Directorate, MAS, Ambulance Union and TIC to address the safety issues raised. The result was to develop a roll cage system to protect the vehicle from collapsing in an accident, and the testing of such a system to determine how well it would hold up in a simulated accident.			Sketch of the TIC Roll Cage design


Vehicle 008 before the test		In 1991, a retired Ambulance (MICA Unit 008) was chosen and construction work with the new roll cage system as specified by TIC was undertaken by Brown Davis Automotive of Bayswater. The design incorporated an outer wrap around cage of 3 pairs of steel tubes bolted through the bodywork at wheel height. The driving cabin and front end of the compartment were braced with steel tubing. For the crash test, all standard equipment was placed within the vehicle and secured with the then current restraining standards. Dummies were also placed on each stretcher (with the then current seatbelt restraints ), and in the Attendant seat behind the driver to represent the crew and patients. A test Driver (George Kovacs) was employed to crash the vehicle.

The test was undertaken at Mangalore Aerodrome and designed to replicate an accident travelling at 100 kmph. A ramp was used to roll the vehicle and to represent the tram safety zones that a vehicle may contact on an emergency drive through Melbourne. On contact with the ramp, the vehicles chassis was noticed to bent significantly behind the drivers cabin. The vehicle was thrown into a spiral roll and turned 250 degrees before hitting the ground, striking the rear corner of the vehicle and ten bouncing onto it’s nose. The vehicle proceeded to then roll sideway reaching forces of 10g.


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The roll cage design was a excellent success, preventing the vehicle’s rear cabin from collapsing and maintain the integrity of the drivers cabin. It was concluded that had this system been available for the Ambulance accident on April 1988, the rear cabin and drivers compartment would not have collapsed. However internally, the integrity of the equipment and stretcher restraints results were a completely different issue. The Ferno Stretcher top broke away from it’s restraints and caused significant damage internally and clearly would have resulted in serious injuries or death of persons in the rear compartment. All other secured equipment managed to remain in place.			Internal destruction of the vehicle

		As a result of the test, roll cages and padding was retrofitted to all non Jakab vehicles still in service throughout Victoria at the time, and all ambulances built following the test have involved design features learned from this test. Current vehicles and equipment restraints are designed to sustain a 20 g forward and a 10 g sideways impact.
Roll cage configuration on operational vehicle