(MSC had undertaken development of the device shortly after the Apollo 6 flight as "insurance" should the sensor prove necessary.) No requirement for a pogo sensor had been identified, said Low. In fact, it was by no means certain how the sensor could be used in flight. Because MSFC was highly confident that the pogo problem encountered on Apollo 6 had been solved, and because no abort criteria could be based on pogo alone, Low argued against the sensor. Even in the unlikely event that pogo occurred on the next Saturn V flight, he argued against an abort unless there was a catastrophic effect on the launch vehicle, in which case abort would be effected using normal abort criteria. For these reasons, no pogo sensor was to be installed on the CSM. A week later, Phillips approved Low's recommendation to halt the pogo sensor development.