From MarineGouge

The basics

A student's Navy Standard Score (NSS) is used to rank aviators at the end of primary (and advanced). The NSS is essentially a comparison of how a student was graded in primary compared to how the 200 previous finishers from their squadron were graded.

Theoretically grades can range from 0 to 100, however scores generally tally from 30 to 80 distributed on a negatively skewed curve. NSS is determined by adding the total graded event score and dividing it by the total graded event MIF for every item attempted on every flight with a + next to it in the MPTS (the syllabus) of the following four blocks of primary; Contact, Instruments, Formation and Navigation.

For instance: Level Speed Change MIF= 3 Score = 5

Course Rules MIF= 3 Score = 5

Headwork S/A MIF= 3 Score = 5

Total Graded Event MIF =9

Total Graded Event Score = 15

Raw Score would be 15/9= 1.6667

If a student got exactly MIF on every item during Primary, their raw score would be 1.0 which is the lowest possible score in Primary, however it is not uncommon for an Initial Progress Check (IPC) to be convened in this event. Never Settle for just MIF!

Once the four phases (Contact, Formation, Instrument, Navigation) are completed, the four phase scores are combined into a final ratio. These "scores" are the overall ratio a student obtains at the end of each phase; TIMS calls it "Stg. Ctg" or something similar. The ratios are multiplied, or weighted, by the number of graded items in that phase, i.e. the sum of the minimum MIF for every item that was graded in the phase (which can be in the thousands). Finally, the sum of the weighted phase ratios are divided by the sum of the minimum MIF for every item in each phase. The generic formula looks something like this:

Final Overall Ratio =[ (Contact Ratio*Contact MIF sum) + (Formation Ratio*Formation MIF sum) + (Instrument Ratio*Instrument MIF sum) + (Nav Ratio*Nav MIF sum) ] / (Contact MIF sum + Formation MIF sum + Instrument MIF sum + Nav MIF sum).

This calculation yields the student's final overall ratio for all of primary (e.g. 1.15). It is this final ratio that is used to determine the student's NSS, based on the performance of the past 200 selectors within that student's squadron only. A 1.15 in one squadron may equate to a 72 NSS, but in another squadron (usually one with 'easier' grading), the same overall ratio might only equate to a 52 NSS. A student's overall phase average can be found on TIMS on the last ATF of that phase under Stg.Ctg. (or similar) and will be a 1.xx number. The sum of the minimum MIF, also known as total graded items, can also be found on the last ATF of the phase. Select print preview for that ATF and the number will be displayed near the bottom; it is usually a larger whole number. However, only the squadron student control knows the approximate correlation between final overall ratio and NSS for the squadron, and may or may not be willing to share that information. It is also worth noting that a student's ground school grades have a small impact on overall NSS, but their exact weight is unknown.

A student's final overall ratio is, obviously, never final until primary is complete. However, for those who are worried/curious about where they stand, one can always calculate their "current" overall ratio by simply taking the numbers from the most recent flight in each phase and plugging into the above formula. Final results, of course, may vary considerably from what a student calculates at some random point in primary, based on how well/poorly the student does in the rest of the syllabus. Because there are more graded items in the contact and, in particular, instrument phases of primary, these effectively have the most impact on one's NSS. Formation has a decent, but not overly large effect, and Navigation has little effect.

To summarize, everyone is curious to know where they stand in primary, but little definitive information is available until the time of selection. One can calculate their current overall ratio to get an idea of how they're generally doing, but this is still very subject to change. The best and quickest way to know how you're doing? Talk to your buds and see what kind of averages they're pulling, if they're willing to share. This will let you know where you fall in the heap, and that may be about the best you can get until your selection week comes.

Minimum Requirements for each platform follow:

Tailhook: NSS of 52+

Rotary: Lucky you, no MIN! (used to be 32)

Maritime:NSS of 32+

MV-22: NSS of 40+; Also wannabe Osprey pilots can only UNSAT 3 flights throughout all of Primary.

For advanced, NSS is now called your composite score. Recent updates to the Composite Score grading follow:

• TGI no longer plays a factor for determining NSS
• Marginals and Unsats now account for 10% of the NSS. Marginal's are worth half as much as an Unsat.
• The size of the group used to determine NSS has been reduced from 200 to 60.
• NSS will now be calculated at the same time for the winging class instead of on an individual basis.
• Events xx86 and xx87 still have no bearing on NSS
• The Composite Score is three times the students flight NSS plus their academic NSS. Primary grades are not utilized in determining final Composite Scores. USMC V-22 syllabus SMA's Composite Score is calculated by Intermediate Flight NSS plus Advanced academic NSS and two times their advanced flight NSS.
• Squadron can setup filters to look at different groups (i.e. by service, class, etc.)
• Special cases can be filtered out of calculations (i.e. exteneded med-down)

Criticism

Due to the nature of flight training, the NSS is highly subjective and has many sources of intrinsic error. Complaints about the NSS system are a staple of flight school parties, but are ultimately a waste of time. Nonetheless, here is a quick primer of some of the more popular complaints so you can bore everyone to tears at your winging party:

• What it takes to get a 5 is not defined anywhere in MPTS. Neither is a three. Only a four is defined; except in cases where three is the training standard for that flight (early FAMS). As a result, different instructors have different standards for giving the 5. Different students have different expectations as well and on occasion have been able to argue for a 5 that was not initially given. This can be fun for sea lawyers but as a system pretty much sucks.

• As a statistic it is not that great. It was clearly not conceived of by any kind of mathematical genius. It probably also wasn't conceived of by a professional teacher. Any serious teacher can tell you there are substantial problems with curved grades, not the least of which may be that aviators which might have been deemed unsafe one year may pass a following year simply because the curve has moved.

• Whatever the talents of the designer of the NSS system, the Navy adopted it and, based on anecdotal evidence, the system almost totally doesn't work. Excellent students often score low, sub par students often score high.

• One of the major failings is that the system is not balanced for the instructors as individuals. It is balanced for a particular squadron - if they, as a squadron, scored the last 200 students low, your low score won't hurt as much - but because of the high churn among IP's and the large differences between instructor's abilities and standards that matters very little. What would matter is how that particular instructor has graded in the past. One easy solution would be to adopt a system similar to the Marine Corps FitRep system where scores are weighted against a RS's previous scores.

• As mentioned above, MIF is not the standard. "MIFing out" a series of flights is a good way to find yourself at a board. Similar to how in (most) colleges the fact that a C average might as well be failing has resulted in grade inflation MIF has become the flight school C. The result is that average students often have their grades inflated above MIF. However, the system is still based around MIF. If the deviation is from an average performance but MIF no longer is equal to average the numbers coming out of the system have less meaning.

• Another popular criticism is that no studies on NSS compared to how aviators have done in the fleet have been done despite repeated calls for them. For example: it ought to be simple to compile the grades of all aviators involved in mishaps or awarded the Distinguished Flying Cross and extrapolate training needs/NSS validity, but it doesn't seem to be done.

• The system can be gamed. Students who go on a cross country will almost always score higher than students who don't. Students who go on a cross country with a santa claus will definitely do better than those who don't. Conscientious instructors want to make sure they grade similarly to their peers. As a result, students who press for higher grades either by pointing out that it was impossible to do better or that their peers got better grades for similar or worse performances will often get better grades. (Be very careful if you try this, not recommended.)

As a result of all this, outside of the Florida panhandle, all anyone cares about is that you have wings. Aside from being top (or bottom) of your class no one cares. Remember, a high NSS guarantees nothing and a low NSS guarantees nothing. Getting Winged guarantees you a chance to fly real birds in the fleet. Learning what they are trying to teach you might save another Marine's life.

More Info

NSS is a favorite topic on Airwarriors. [Go there for more information.]