While a senior in high school in Oklahoma in March 1943 I enlisted in the Navy in the Navy V-5 program. I was called to active duty on July 1, 1943. I was sent to Central Missouri State Teacher's College in Warrensburg, Missouri. My designation was changed from V-5 to V12A. I assume the "A" might have meant aviation. A semester was of 4 months duration. I was scheduled to attend 2 semesters and then be transferred to a navy pre-flight school. During my second semester, several of us were given a test and the option of going to pre-flight school or to a major university for NROTC. There were other students at Warrensburg that had the designation of V-12. They were to attend 4 semesters and then attend a navy midshipman school for 4 months and then be commissioned as Ensigns in the navy. My group of 12 were lined up alphabetically on a bench and called in one by one. The first 11 received orders to NROTC at UCLA. I was the last one called in and was told there were only 11 quotas for UCLA and that I would go to Notre Dame NROTC. I was at Notre Dame (still with a V-12 designation) for 5 semesters of 4 months each. We took 18-20 hours per semester and graduated afte 28 months (8 in V-12 plus 20 in NROTC). I was an Ensign and a college graduate at the age of 20. I remained in the navy (mostly submarine duty) until I retired in 1970 as a Captain. Hope this helps you understand the programs.
Captain Robert Thomas U. S. Navy (Retired)