Quality control is a difficult thing to accomplish. It has to be designed into the entire system. More than that, it has to be on everyone’s mind.

In the last half-decade, the Russians lost a payload because the upper stage was used in a way for which it had not been designed. For its originally intended use, it did not matter how the propellant lines were routed, so it was designed with optional routing. For the new use, one of the routing methods and the delay time between engine burns allowed the propellant in that line to freeze between the first and second engine burns, but no one understood that possibility when they decided to use the upper stage in the new way. This part of quality control was not on people’s minds at the time of that decision.

I hope that the Russians are finally getting a handle on quality control, but it takes constant effort on the part of everyone involved in the whole system, even to those who do not seem involved, such as the janitors and the secretaries.