Goodyear's new RunOnFlat technology is based on the concept of reinforced sidewalls inside the tyre. When a standard tyre deflates, it simply collapses under the weight of the car, allowing the beads to come off the rim and the sidewalls to be squashed onto the road. The pressure totally destroys the tyre within a few miles. The reinforced sidewalls in Goodyear's RunOnFlat tyres keep the tyre on the rim and succeed in carrying the weight of the car for up to 50 miles after a puncture with complete air pressure loss.
Since your tyres will simply keep going after they've suffered pressure loss, RunOnFlat technology requires the presence of an on-board TPMS (Tyre Pressure Monitoring System) that lets you know that your tyre requires servicing. Without such a system, you would have no way of knowing that your tyre had suffered a puncture or a blow-out.