The OAR is not a separate test — it is the first three subtests of the Aviation Selection Test Battery, scored on their own for candidates who are not applying to fly. Navy OCS applicants, and a range of other non-aviation officer programs, sit exactly these three: Math Skills, Reading Comprehension, and Mechanical Comprehension. Aviation applicants take the same three plus the rest of the ASTB-E.

The thing worth knowing before you study is that all three are COMPUTER ADAPTIVE. NAMI states the test is drawn from an item library of several hundred items per subtest, that the number and difficulty of questions varies between examinees, and that you cannot skip an item or go back and change an answer. That has two consequences most study plans miss. First, no fixed-length practice test can mirror it, so pacing yourself against a "90-question OAR" is pacing against a version that no longer exists. Second — and this is the Navy’s own advice — random guessing as the clock runs out is usually worse than leaving items unanswered, because the unfinished-item penalty is often smaller than the damage a string of wrong answers does to an adaptive score.

Adaptive practice is therefore the honest preparation for an adaptive test, which is what Keentune does by default: every question is chosen near your current level and moves with you, and every explanation names the principle and diagnoses the trap rather than just marking you wrong. Note also that no calculator is permitted — relevant formulas are provided — so the Math Skills work that pays is mental arithmetic and algebra you can run on scrap paper.