In a recent article on Ancestral Findings details how the 1973 fire can affect military record availability.
Many U.S. Army or Air Force records (1912-1964) were destroyed at the National Personnel Records Center in St. Louis, Missouri, in a devastating fire on July 12, 1973.
The article explains how "over 6.5 million records were able to be recovered from the building after the fire, though they were in terrible condition. They were carefully dried, sprayed with mold repellant, and pieces of records that were charred began to be put back together in a painstaking, careful, and slow process."
At the 2015 NGS conference in St. Charles a representative from the Center provided a comprehensive explanation of what has been done to ensure veterans, historians and genealogists have access to the records. He explained that the only way to know for sure whether a record is available is to request it from the NPRC. More than 40 years later many records have yet to be scanned. Instead records are found, copied and preserved by request only.