OAR study guide
OAR Study Guide: the Subtest Blueprint, Weight Chart and a Four-Week Study Plan
Three subtests, one score, and a fixed pecking order for your prep time. This guide reads the Officer Aptitude Rating the way you should read a question — heaviest first, distractors last — then points you to a deep-dive for each subtest and a free drill to test it.
Orientation
How to Use This Guide
This is a blueprint, not a quiz. There is no timer on this page and nothing to answer here — the drilling lives on the free OAR practice test, and this guide’s job is to tell you where to point it. Work top to bottom: read the weight chart, take the subtest sitting at the top of it first, open that subtest’s deep-dive, then go rule out real questions until the pattern is automatic. The order is the whole point — spend your heaviest effort where the bank is heaviest.
3
OAR subtests
Math · Mechanical · Reading
36 · 33 · 31
This guide’s weighting
Share of our bank
2
Deep-dives live
Reading Comprehension is next
Exam structure
The Three-Subtest Blueprint
Read the answers before the question and you learn the exam rewards recognition over recall; read the blueprint before the syllabus and you learn the same thing about your study time. The three OAR subtests are the Math Skills Test, the Mechanical Comprehension Test and the Reading Comprehension Test. This guide weights its own question bank 36 / 33 / 31 across them — our prioritisation, not an official NAMI item count — and that ranking is your priority list: the heaviest subtest earns the most of your hours.
The weight chart is a study schedule wearing a bar chart's clothes: heaviest subtest, most of your time.
This guide’s own weighting of its question bank — not an official NAMI item count.
Table of contents
Where to Spend Your Time
Take the subtests in weight order. Each tile opens a deep-dive that does the elimination legwork for that subtest — the item types, the high-yield topics, and the distractor patterns you can rule out on sight. The Reading Comprehension deep-dive is still being built; the blueprint above already tells you it is the lightest slice, so it waits its turn.
Subtest · 36
Math Skills Test
Arithmetic, algebra, geometry and word problems — rule out answers of the wrong magnitude before you compute.
Subtest · 33
Mechanical Comprehension Test
Levers, pulleys, gears, fluids and pressure — eliminate any option that points the force the wrong way.
Subtest · 31
Reading Comprehension Test
Supported-conclusion items — the answer the passage backs, not the one that is merely true in the world.
Coming soon
Study plan
A Four-Week Study Plan
Four weeks, weighted the way the blueprint is: the most reps where the bank is heaviest, a lighter pass where it is lightest, and a final week that mixes everything so you practise choosing which subtest a question even belongs to. The calendar is a template — the sequence matters more than the number of weeks, so stretch or compress it to fit your own timeline.
Week 1 — Math Skills Test
Start here; it is the heaviest slice of the bank. Drill arithmetic, algebra and geometry, and practise ruling out answers by estimation and units before you commit to the full calculation.
Week 2 — Mechanical Comprehension Test
Move to the second-heaviest subtest. Review levers, pulleys, gears and pressure until you can eliminate any choice that violates the principle shown in the diagram.
Week 3 — Reading Comprehension Test
The lightest slice, and the one where reading the four answers first pays most: hunt the passage for the claim each choice makes, then strike the ones that overreach what the text actually supports.
Week 4 — Mixed elimination drills
Run mixed sets on the practice test so you switch subtests cold, and revisit every question you missed until its trap is obvious on sight.
Resources
Free vs Paid — What Actually Helps
Content is the cheap part of this exam — reps and honest feedback are what move a score, and you can get both for free. Spend money only where it buys structure or volume you would not otherwise build, and never on a promise: no book, course or site can guarantee a number, and anyone who says otherwise is selling the guarantee, not the score. If you are an aviation candidate sitting the full battery rather than the OAR subset alone, start from the ASTB practice test instead of this OAR-only track.
| Resource | What it is good for | Watch for |
|---|---|---|
| Free browser practice (this site) | Timed elimination reps across all three subtests, with a worked rationale on every item. | It is independent practice built to the public outline — not the administered ASTB-E or retired items. |
| The subtest deep-dives | Item taxonomy, high-yield topics and the exact distractor patterns to rule out. | Read the guide, then drill — reading alone does not build the reflex. |
| Official outline & guidance | NAMI and your recruiter for scoring, retakes and test-day rules such as calculator and scratch-paper policy. | Rules change — confirm the current policy at the source before you rely on it. |
| Paid books / courses | Extra structure and item volume, if that is what you are missing. | No product can promise a score; weigh the cost against the free reps you already have. |
FAQ
OAR Study Guide FAQ
How should I study for the OAR?
Study in weight order. This guide puts the Math Skills Test first because it is the heaviest slice of our bank, then the Mechanical Comprehension Test, then the Reading Comprehension Test. Read each subtest’s deep-dive, then drill it on the free practice test with disciplined elimination — rule the impossible answers out first and decide between the two that are left.
What is the best OAR study guide?
The one built to the published subtest outline and honest about what it can promise — which is reps and feedback, never a number. Confirm scoring, retakes and test-day rules against NAMI and your recruiter, use a guide that routes you into practice rather than just reading, and treat any “guaranteed pass” claim as a reason to walk away.
How long should I study for the OAR?
Long enough to make the traps automatic — the four-week sequence above is a template, not a rule. Weight your calendar the way the bank is weighted, protect a final block for mixed drilling, and stretch or compress the weeks to fit your test timeline. No single minimum fits everyone.
Which OAR subtest matters most?
For your study time, the heaviest one: this guide weights its bank 36 / 33 / 31, so the Math Skills Test earns the most attention, then the Mechanical Comprehension Test, then the Reading Comprehension Test. For your score, how the subtests roll into the OAR and any branch or program minimum is set by NAMI and your community — not by this weighting.
OAR Exam Prep
Take the OAR question bank with you
Get the app for the full bank across all three OAR subtests, sampled to the real Math / Mechanical / Reading weighting — or keep drilling free on this site.