This discussion is to give a little more space to possibly explain what a recruiter might mean by an A (Alpha) or B (Bravo) Nuke. Once my brain was jogged with mention of the Nuke Test, I went hunting the internet and found something I referred to with my own son, but since there was never any mention of him being A or B Nuke, I never inquired as to what NFa or NFb was. NAPT is the link to the website where I am gleaning this information from. I am not copying, since I am not sure of copyrights on the website, but hopefully, I can explain it well enough that you can interpret their information.
So, to qualify Alpha or as they state NFa - certain line scores on the ASVAB have to be scored high enough to qualify for the Nuclear Field (NF) Program outright. If I am reading the chart correctly, at least one line score must be greater than or equal to 252 and both lines scores have to be greater than or equal to 235. Otherwise...
To qualify Bravo or as they state NFb - both ASVAB line scores must be greater than or equal to 235 and they must also take the NAPT (Navy Advanced Placement Test) and score at a certain high level on those line scores as well to qualify for the NF Program.
There are some comments about a Type 3 academic determination and waiver determinations that I am not fully understanding, so I will leave out.
Something that I recall from the recruiters talking to me about my son, the line scores they are looking for the Nuclear Field are a certain combination of different subjects that make up their two line scores. The abbreviations with equivalents of those subjects are listed at the bottom of that page section.
So, if your recruit qualified Alpha Nuke that means they scored high enough on their ASVAB line scores to not need to take the additional NAPT. If they qualified Bravo, then their line scores on the ASVAB were high enough to indicate that they had the aptitude for doing the Nuclear Field, but they want them to take a supplementary test (NAPT) which actually tests them on specific mathematical and scientific information. Your recruit will not be allowed to tell you what is on the test, they are not even allowed to see which questions they got wrong as I recall. If you are reading this in search of study guides for the NAPT there are no official study guides, not like they have for the ACT, SAT, and maybe ASVAB. What you find in a Google search for a NAPT study guide is not official. The test is kept very secured and if compromised, there can be delays in being able to take it.
Then there are the exceptions to the rule: Even if your child has scored well on the ASVAB overall and especially on the individual line scores needed for Nuclear Field qualifying, they may still have to take the NAPT and achieve the qualifying score on it before you can be signed on for the Nuclear Field. The NAPT is a supplementary test for the Nuclear Field and it is my understanding that if the Navy feels they need it taken before they will sign up a recruit just based on their ASVAB scores then they will. That was the case with my son. Outright, he should have been considered an Alpha recruit from his very high ASVAB score and also high NF line scores.
However there seem to be several scenarios where the Navy reserves the right to do an extra determination that a recruit is qualified to enter the NF program and that could be: they are not confident in a person's transcript, such as from a parochial, private or home school. A person has been out of high school for awhile, or they did not take a math class their senior year, or concerned with the strength of their science or math background. Others were probably mentioned when I searched this almost 4 years ago, but I don't recall now.
So yes, the difference between an Alpha and Bravo Nuclear Recruit is bottom line paperwork, but it still requires extra testing. And the extra testing may not be entirely because they did not have a strong enough ASVAB score. It could in fact be very high but other things don't add up on their checklist. In the end, all recruits going into the Navy are on equal footing. What Nuclear rating a SR receives at BC is decided, to the best of my knowledge, on several factors: needs of the Navy, recruit preference and probably ASVAB scores - remember it is an aptitude test - and which one of those three is given higher priority at any given time could be as different as day is from night. At least that is what I have noticed from reading other posts and discussions from over the years.
There are some other things that also factor into being NF qualified before going to BC and that is passing security and medical clearance as well as general Navy enlistment requirements.
Once in school, it is likely that your sailor, especially if they are of a competitive nature and certain personality will push themselves and aim to be at the top of the class, but when all is said and done - If you pass you pass and in the fleet your test scores and class average doesn't matter - Unless you choose not to uphold a Nuke standard for yourself and your team - You are all Nuclear Qualified.
(Italics is my own comment and emphasis.)