OAR study guide
OAR · Work through your exam, one topic at a time.
The Officer Aptitude Rating (OAR) is a score reported by the Aviation Selection Test Battery (ASTB), the battery the U.S. Navy and Marine Corps use when screening applicants for officer commissioning programs, most visibly aviation and naval flight officer slots but also several other designators. The OAR is not a separate exam you sit for on its own: it is a composite computed from your performance on three ASTB subtests - Mathematics (Math Skills), Reading Comprehension, and Mechanical Comprehension. Because the three feed a single number, a weak area drags the composite down even if the other two are strong, so balanced preparation matters more than specializing. Topics on this exam: Mathematics (Math Skills content area), Reading Comprehension, and Mechanical Comprehension. The OAR study guide has 3 sections and about 861 words.
01Mathematics (Math Skills)
Build fluency in arithmetic with fractions, decimals, and percents; ratio and proportion; linear equations; unit conversions; averages; and basic geometry (perimeter, area, volume, right-triangle relationships). Most questions are word problems, so translation skill matters as much as computation. Percent change base: a 20% increase followed by a 20% decrease does not return to the original value. Always apply each percent to the new amount.
290 words, about 1 min02Reading Comprehension
Questions test main idea, supporting detail, inference, author's purpose and tone, vocabulary in context, and logical structure such as cause/effect or compare/contrast. Read for the passage's argument and organization, not just isolated facts. True but irrelevant: a choice may be factually supported yet fail to answer the specific question. Extreme language: words like always, never, only, and must often signal a wrong inference.
288 words, about 1 min03Mechanical Comprehension
Know how simple machines trade force for distance: levers, pulleys, inclined planes, wedges, screws, and wheel-and-axle systems. Understand mechanical advantage, torque, work and energy, pressure, buoyancy, friction, and gear direction and speed. Many questions ask which setup requires less effort or moves faster. Force versus distance: a machine can reduce force but then requires more distance; work input is not reduced.
283 words, about 1 min