AFOQT study guide

An analogy matches a relationship between words. Knowing what the words mean is the starting point; explaining how they connect is the part that decides the answer.

1. Turn the first pair into a short sentence: X means the opposite of Y, X is a stronger form of Y, or X produces Y.
2. Use a precise relationship. “These words go together” does not distinguish the right answer from a plausible distractor.
3. For a completion question, apply that sentence to the third word before reading the options. For a pair-matching question, test each complete pair.
4. Check degree and word sense. Slightly annoyed and furious are related, but they are not synonyms of equal intensity.
5. Keep the option that preserves the relationship without adding a new story or an unusual meaning.

Common mistake: Selecting a word from the same topic instead of one that has the same relationship. A dim room and an opaque screen both affect visibility, but dim is not the opposite of opaque.

Practice tip: After each missed question, write the relationship in a few words. Review recurring errors by relationship, rather than memorizing the particular pair.

Many relationships work in only one direction. A plan guides a finished product; a finished product is not the plan that guided it. A correct option must preserve that order.

1. Read the source pair left to right and name what the first word does in relation to the second.
2. Use an arrow in your reasoning: plan → product, part → whole, cause → effect, or worker → tool.
3. Apply the same arrow to each answer. Eliminate a pair that reverses it, even if its two words otherwise fit perfectly.
4. Check the exact roles. A tool used by a worker differs from a material transformed by that worker.
5. Read the complete analogy once more before selecting it; the same connecting sentence should fit both halves.

Common mistake: Recognizing the right two concepts but accepting them in reverse order.

Practice tip: Say the linking sentence aloud during untimed practice. When the relation becomes clear, shorten it to a two-word label for timed questions.

A type belongs to a category; a part belongs inside a whole. Those relationships look similar in a loose sentence such as “X belongs to Y,” so make the sentence more specific.

1. Try “X is a kind of Y.” If it is true, the pair may be a member → category relationship.
2. Try “X is a component of Y.” If that is true instead, look for another component → whole pair.
3. Distinguish an individual from a collection, a defining property from a common association, and an example from its broader class.
4. Preserve the level of specificity: a particular kind of object should map to a comparable kind, not to its material or usual location.
5. Check every option against the same sentence. Do not switch from “a kind of” to “a part of” halfway through the analogy.

Common mistake: Using “belongs to” so broadly that both a subtype and a physical component seem correct.

Practice tip: Before checking an explanation, label each tempting option as type, part, material, creator, or location. This makes near misses easier to reject on the next attempt.

Keep the quantity and its unit attached to every number. A rate compares two different quantities, such as miles per hour; a ratio compares parts or amounts. Work problems become simpler when you express each worker’s output as a fraction of one job per unit of time.

1. Put all times and distances in compatible units before combining them.
2. Use distance = speed × time, or output = rate × time. Rearrange only after deciding which quantity is unknown.
3. For a worker who completes one job in t hours, the work rate is 1/t job per hour. Add rates for workers contributing to the same job, or subtract a drain or loss rate.
4. For a ratio a:b between two parts of the same whole, the whole has a + b equal parts. Find the value of one part before scaling either quantity.

Common mistake: Adding or averaging completion times instead of adding work rates. Two workers do not need the sum of their individual times when they work together.

Practice tip: Cancel units on paper and use simple fractions. For speed questions involving minutes, write the time as a fraction of an hour before multiplying.

The base is the quantity that represents 100%. It can change during a problem: a discount may apply to a marked price, a fee to a selling price, or an interest rate to the original principal. Write down the base at each stage.

1. Find a percent of a quantity by multiplying by its decimal or fraction form.
2. Represent an increase of p% by multiplying by 1 + p/100; represent a decrease by multiplying by 1 − p/100.
3. Apply successive factors in sequence. To work backward from a final amount, divide by the applicable factor.
4. For a percent change or profit rate, divide the change by the base named in the question. Cost and selling price are different bases.

Common mistake: Subtracting 15 from 25 and calling the result a 10% profit. The markup and discount apply to different dollar amounts.

Practice tip: Use convenient fractions: 25% = 1/4, 12.5% = 1/8, and 6.25% = 1/16. For simple interest, apply principal × rate × time; do not compound unless instructed.

Identify one unknown and express the other quantities in terms of it. The most useful equation usually comes from a fixed total, an equal cost, a difference, or an unchanged quantity. Check that the solution is possible in the original situation.

1. Choose a variable for a quantity the question needs, with its unit.
2. Translate words carefully: “5 fewer than twice x” is 2x − 5, and “in 6 years” adds 6 to every person’s current age.
3. Build the total or equality, solve it, and substitute your answer back into the original relationships.
4. For counts of packages, people or containers, reject fractional or negative counts. If several whole-number combinations are possible, compare the requested costs or limits.

Common mistake: Finding the variable correctly but answering for the wrong group. Here the first solved value is Team B’s size, while the question asks about Team A.

Practice tip: Underline the final quantity being asked for. A short check of both the total and the stated relationship can catch an arithmetic or translation error.

A geometry word problem first requires the right kind of measurement. Fencing needs a boundary length, flooring needs an area, and liquid or concrete needs a volume. Draw a quick labeled sketch and keep units consistent.

1. Choose the dimension of the answer: length, square units for area, or cubic units for volume.
2. Split a composite shape into simple nonoverlapping pieces, or subtract a clearly defined cutout from a larger shape.
3. Convert dimensions before calculating, or use the correct squared or cubed conversion factor afterward. One square yard equals nine square feet.
4. Apply practical constraints last: round whole cans or boxes upward when all material must be covered, and include spare material only when specified.

Common mistake: Dividing square feet by 3 because a yard contains 3 feet. Both dimensions change, so an area conversion uses 3² = 9.

Practice tip: Check the unit of your result before choosing an option. Adding side lengths cannot produce an area, and a tank’s footprint alone does not determine its capacity.

Word Knowledge presents a word and asks for its nearest synonym among five choices. The current AFOQT section has 25 questions in 5 minutes: an average of 12 seconds per question. Build accurate recognition first, then practice retrieving meanings quickly.

1. Put the headword into a short definition of your own before looking for an answer. This reduces the chance of choosing a familiar-looking but unrelated word.
2. Match the grammatical use as well as the meaning. A verb should be compared with the actions expressed by the choices; an adjective should be compared with the qualities they describe.
3. Separate a synonym from an association. A word can describe a cause, consequence, or common companion of the headword without meaning the same thing.
4. Choose the closest meaning that the choices support. During timed practice, avoid spending so long on one unfamiliar word that you leave known words unreached.

Common mistake: Choosing a word because it belongs to the same situation. Admiration can motivate emulation, but admiring someone does not itself mean following their example.

Practice tip: After a drill, make a short review list: headword, plain-language definition, and one original sentence. Revisit the list after a delay and try to recall each meaning before revealing it.

More demanding vocabulary questions test exact meaning, not specialist trivia. Keep track of the dimension a word describes: duration, intensity, attitude, certainty, or purpose. Similar-looking words and related ideas can point in different directions.

1. Identify the central feature of the meaning. If a word describes duration, do not substitute a choice that only describes weakness or unpredictability.
2. Check familiar roots and prefixes as clues, not proof. The full word can have an established meaning that cannot be recovered reliably from its spelling alone.
3. Test the strongest choices in a simple sentence while preserving the intended sense. Prefer the choice that changes the meaning least.
4. Use explanations to learn distinctions, then practice with fresh headwords. Faster recall comes from knowing the meanings rather than memorizing answer positions.

Common mistake: Treating all broadly similar negative or positive words as interchangeable. A short-lived event is not necessarily weak, unexpected, or recurring.

Practice tip: Study small contrast sets and write a sentence that separates each pair. In timed practice, keep the five-minute section limit; in untimed drills, work through every rejected option before moving on.

An equation stays equivalent when you perform the same valid operation on both sides. Before calculating, look for a common denominator, a term that can be eliminated, or a restriction on the unknown.

1. Work in exact fractions when possible. Clear fixed denominators by multiplying every term by their least common multiple.
2. Distribute signs carefully, combine like terms, and isolate the unknown. If an inequality is divided by a negative number, reverse its direction.
3. For two equations in two unknowns, use substitution or multiply one equation so that addition eliminates an unknown.
4. Check the original equation. Values that make an original denominator zero remain excluded, even if a factor cancels later.

Common mistake: A minus sign before parentheses applies to every term. Here −3(x + 2) becomes −3x − 6, not −3x + 6.

Practice tip: After finding an answer, substitute it into the original problem. This often catches a sign error faster than repeating the algebra.

Exponent rules describe repeated multiplication. Factoring reverses expansion and exposes the parts of an expression that can be simplified or set equal to zero.

1. For the same nonzero base, add exponents when multiplying and subtract them when dividing. A power raised to a power multiplies the exponents.
2. A negative exponent means a reciprocal; it does not make a positive base negative. Preserve the difference between (−a)² and −a².
3. Distribute a power over products, not sums. Expand a sum such as (x + 3)² before combining like terms.
4. Factor out a common factor first, then look for products or differences of squares. Apply the zero-product rule only when the product equals zero.

Common mistake: When dividing powers, subtract the entire denominator exponent. In this example 6 − (−1) is 7, not 5.

Practice tip: Use a small nonzero value to check a simplification. Keep factors separate until the exponent and sign rules are clear.

First identify which quantity is being asked for. Perimeter follows the boundary, area covers a flat region, and volume fills a solid; these use different formulas and different units.

1. Label the given lengths and infer missing ones from angle relationships, symmetry, the Pythagorean theorem, or similarity.
2. Split a composite figure into familiar shapes. Add the areas you keep and subtract the areas removed.
3. For perimeter, trace the actual outside boundary. A removed straight segment may be replaced by a curved edge.
4. Keep π or radicals exact when the choices do. For similar figures with length factor k, areas scale by k² and volumes by k³.

Common mistake: Do not keep the removed 8 cm edge in the perimeter, and do not use the diameter as the radius in the area formula.

Practice tip: Mark which edges remain before adding a perimeter. Check that an area has square units and a volume has cubic units.

An informational passage explains a relationship: how something changed, why a result occurred, what a comparison shows, or where an explanation has limits. Its main idea should account for the important details without turning a qualified finding into a universal claim.

1. Identify the subject, then state what the passage establishes about it. A subject such as “weather observations” is not yet a main idea.
2. Map the main relationships: cause and effect, old and new methods, a finding and its limitation, or a process and its result.
3. For a detail question, return to the relevant sentence and check nearby qualifications. For an inference, connect supplied facts without adding a new fact of your own.
4. Compare the scope of the options. An accurate example may be too narrow, while a broad statement may go further than the evidence.

Common mistake: Choosing “the region’s climate became cooler.” The passage does not establish a regional change, and the nearby records, which showed little change, argue against that confident conclusion.

Practice tip: After each paragraph, mentally summarize its job in a few words. Keep those notes about ideas, not a list of disconnected details.

Argument passages ask you to understand what a writer supports, how the reasoning works and where it stops. Your own agreement with the policy or opinion is separate from whether a particular answer accurately describes the text.

1. State the conclusion as a claim the writer wants the reader to accept. Distinguish that claim from the examples used to support it.
2. Notice concessions and qualifications. A writer can accept an objection without abandoning the main position.
3. Ask what connects the evidence to the conclusion. Does a successful trial justify the same claim for other people, conditions or purposes?
4. When comparing answer choices, preserve the writer’s level of certainty. “A reason to try” is weaker than “proof that it will work everywhere.”

Common mistake: Treating a qualification as complete opposition, or assuming that a favorable example proves every broader version of a proposal.

Practice tip: Underline the difference between the claim supported by the evidence and a stronger claim the passage does not establish.

A technical passage may describe an unfamiliar device or process, but the reading task should be solved from the information it supplies. Keep the passage’s definitions and operating conditions in view rather than substituting what you know about a similar system.

1. Translate each defined term into a plain-language role: what it measures, changes, permits or prevents.
2. Follow the order of operations. Distinguish a condition that starts a step from the result that completes it.
3. Mark restrictions such as “only after,” “while,” “unless” and “provided that.” A process can have more than one necessary condition.
4. For a changed-condition question, trace only the affected parts of the described process. Do not assume that an earlier valid result stays valid after the conditions change.

Common mistake: Assuming that moving to a warmer room necessarily invalidates every reading, or that completing the first step eliminates the second requirement. Neither follows from the stated process.

Practice tip: Use a short sequence such as “flush → verify stable interval → store” to keep the conditions separate, then test the proposed change against that sequence.

Situational Judgment presents a situation and five actions. Rate how likely you would be to take each action. Several actions can receive the same rating. In these original practices, the notes discuss possible effects; there are no scored or preferred likelihood patterns.

1. Establish who needs what information, what each person is responsible for and what the scenario says about time.
2. Read all five actions independently. An action may help one part of the work while creating difficulty elsewhere.
3. Consider how you ordinarily communicate, respond to feedback and adapt when someone has different information.
4. Choose your own likelihood for every action. The scale is Very Unlikely, Unlikely, Unsure, Likely and Very Likely; it is not a ranking that uses each label once.

Common mistake: Treating the five actions as a best-to-worst ordering, or changing an honest rating simply because the same label has already been used.

Practice tip: After rating, compare your interpretation of the stated facts with the reflection notes. Do not turn the notes into a personality answer key.

Leadership situations can involve delegating work, receiving criticism or adapting a plan. The scenario supplies the role and constraints; military knowledge is not needed. Our Leadership grouping is an editorial practice theme, not an official score category.

1. Separate decisions you can make from decisions the scenario reserves for someone else.
2. Notice any new information or feedback that affects the original plan.
3. Consider what each action communicates, who does the work and what happens to the remaining deadline.
4. Rate how likely you would be to take each action. Reflect on consequences without assigning yourself an officer suitability label.

Common mistake: Assuming that taking all the work yourself, referring every decision upward or agreeing with every suggestion always means effective leadership.

Practice tip: Look for the actual authority and resources stated in the scenario. Avoid inventing extra staff, a new deadline or an unstated rule to justify a response.

These scenarios explore how information is reported, responsibilities are handed over and commitments are explained. The action notes describe consequences within the stated situation. They do not grade your character or identify official preferred answers.

1. Distinguish what is verified, what is estimated and what remains unknown.
2. Notice who has already received information and who will rely on the next update.
3. Consider the effect of timing, disclosure and ownership in each proposed action.
4. Use the likelihood scale to describe your own response, including when more than one action deserves the same rating.

Common mistake: Equating a corrected file with a corrected understanding, or assuming that another person has accepted an action simply because an email was forwarded.

Practice tip: Use the details given. When an action’s outcome is uncertain, acknowledge that uncertainty rather than assuming an intention or consequence the scenario does not establish.

Separate mass, force and acceleration before calculating. The same gravity that gives an object weight also curves a satellite’s path; the basic astronomy questions require you to distinguish orbital motion, seasons and lunar phases.

1. Draw or list the forces acting on the one object. Opposing forces subtract; perpendicular forces require vector addition.
2. Use net force = mass × acceleration. For momentum use mass × velocity, and for torque use perpendicular force × distance from the pivot.
3. In orbit, gravity supplies inward acceleration while the satellite retains sideways velocity. For unchanged masses, doubling center-to-center distance reduces gravity to one-fourth.
4. Earth’s axial tilt explains the seasons. The visible fraction of the Moon’s sunlit half explains normal lunar phases; do not substitute Earth’s shadow for that explanation.

Common mistake: Treating constant speed as proof of zero acceleration even when direction changes, or confusing distance from Earth’s center with height above the surface.

Practice tip: Write the relationship first and check units. For astronomy, state the physical cause before looking for a matching answer.

Track what is conserved and what is being transferred. Electrical circuits, moving objects and heating problems all involve energy, but power, temperature and energy are different quantities.

1. Work is force along the motion × distance. Kinetic energy depends on speed squared; gravitational potential energy changes by mgΔh.
2. Power is energy transferred per second. Useful output equals input multiplied by efficiency.
3. For heating without a phase change use Q = mcΔT. During a phase change, energy can alter particle arrangement without changing the equilibrium temperature. Conduction needs contact, convection uses moving fluid and radiation can cross a vacuum.
4. For a resistor use V = IR and P = VI. Series resistances add and share a current; parallel branches share a voltage. Changing magnetic flux can induce a voltage.

Common mistake: Using the total supply voltage across every resistor in a series circuit, or treating watts as an amount of energy instead of a transfer rate.

Practice tip: Keep joules, watts, volts and amperes separate. A unit check often eliminates a plausible-looking numerical distractor.

Use a small set of wave and pressure relationships, then check the conditions. Sound needs matter, light can travel through a vacuum, and liquid pressure is determined by depth rather than container shape.

1. For any traveling wave, v = fλ and period T = 1/f. In a fixed medium, increasing frequency usually shortens wavelength at unchanged speed.
2. Sound is a mechanical wave. An approaching source raises the observed frequency; loudness is a separate property. Electromagnetic waves include radio, visible light and ultraviolet.
3. Measure optical angles from the normal. Reflection preserves the angle; entering a slower optical medium bends an oblique ray toward the normal. At a stationary boundary, frequency stays fixed while wavelength changes.
4. Fluid pressure increases by ρgh with depth. Buoyancy equals displaced fluid weight, and steady incompressible flow obeys area × speed = constant. Use ideal-flow pressure arguments only when their assumptions are stated.

Common mistake: Confusing a ray’s angle to a surface with its angle to the normal, or using pipe diameter directly when the relationship requires cross-sectional area.

Practice tip: Identify what stays constant before taking a ratio. Sketch the normal or write the area–speed product if the wording is easy to misread.

Start with particle counts, then distinguish chemical rearrangements from changes to nuclei. Introductory chemistry also asks you to read formulas, conserve atoms and reason about solutions and reaction energy.

1. Atomic number counts protons. Mass number counts protons plus neutrons. Electron gain or loss changes charge; changing neutron count gives an isotope of the same element.
2. Ionic bonding involves attraction between charged ions; covalent bonding involves shared electrons. Main-group periodic-table columns have similar valence-electron patterns.
3. Balance equations by changing coefficients, never the subscripts that define a substance. A coefficient multiplies every atom in a formula; parentheses multiply everything inside.
4. In a closed chemical reaction, atoms and total mass are conserved. Dilution changes concentration without changing solute amount; acids and bases can neutralize to form salt and water. Exothermic reactions release heat and catalysts lower an activation barrier.
5. Nuclear fission splits a heavy nucleus; fusion combines light nuclei. For radioactive decay, halve the amount once for each half-life rather than subtracting a constant amount.

Common mistake: Treating electron loss as a change of element, changing chemical subscripts to balance an equation, or treating half-life decay as a constant subtraction.

Practice tip: For each choice, identify whether the question concerns electrons, nuclei, whole molecules or a bulk solution. Keep the level of description consistent.

Table Reading is a lookup task. X identifies a column and Y identifies a row. The table entry at their intersection is the answer; you do not add or multiply the coordinates.

1. Read the requested X and Y, including their signs.
2. Locate X across the column headings: negative values are left of 0 and positive values are right of 0.
3. Locate Y down the row labels: positive values are above 0 and negative values are below 0.
4. Follow the row to the chosen column, read the entry, and check the two labels once more.

Common mistake: Swapping X and Y, or dropping a minus sign, selects a different cell even when the tracking itself is accurate.

Practice tip: Use the untimed coordinate drill until sign and axis errors are rare. Then add time pressure in the full Table Reading section.

A consistent lookup routine is faster than changing methods on each question. Confirm the labels, track the row, and then choose the matching entry. Speed comes from avoiding repeated searches.

1. Read the two requested coordinates before searching the table.
2. Find the target column and row using 0 as a reference when useful.
3. Keep your place along the row as you move to the target column. Watch for drifting one row or one column.
4. Match the cell value to an answer, then reset to the new coordinates for the next question.

Common mistake: Moving quickly but accepting the value one cell beside the requested intersection. The nearby numbers are often plausible answer choices.

Practice tip: The timed practice contains 40 questions in 7 minutes: about 10.5 seconds per question on average. Learn the routine accurately first, then practice maintaining it at that pace.

The small aircraft symbol and white zero marker stay still. The horizon and black pointer move. Read their positions before looking at the answer choices.

1. Horizon below the aircraft symbol means nose up; horizon above it means nose down.
2. For a right bank, the black pointer moves left of the fixed zero marker; for a left bank, it moves right.
3. Treat bank as the pilot’s left or right. An aircraft flying toward you reverses those sides on the page.

Common mistake: Calling a left-moving pointer a left bank. The moving horizon and its pointer turn opposite the aircraft.

Practice tip: Read pitch first, bank second. Then use the nose, canopy and tail to check which way the aircraft faces.

The compass arrow gives the direction of the aircraft’s nose. Your viewpoint stays south of the aircraft, looking north at its altitude.

1. North is away from you and south is toward you.
2. East is right on the page and west is left.
3. Diagonal headings combine these directions. Southeast points right and toward you; northwest points left and away.

Common mistake: Moving your viewpoint with the aircraft, or reading the blunt tail as its nose.

Practice tip: Locate the pointed nose and glass canopy. A dark circular exhaust marks the rear of this practice aircraft.

An aircraft must match heading, pitch and bank together. A choice that matches two readings can still be wrong.

1. Read the compass arrow and hold that heading in mind.
2. Check whether the horizon is above, through or below the fixed aircraft symbol.
3. Read the black bank pointer relative to the fixed zero marker, then inspect all four aircraft.

Common mistake: Choosing a correct bank while overlooking a reversed heading or nose-up attitude.

Practice tip: Eliminate a drawing as soon as one instrument contradicts it, then verify every reading on the remaining choice.

A rectangular block can touch several other blocks across one broad face. Count touching blocks, not faces, and include partial face contacts.

1. Find the outer edges of the marked block and follow its full length.
2. Check the layer above, then the layer below. Perpendicular long blocks may each cover only part of the target face.
3. Check the four side faces. Count each other block once; ignore contacts only at edges or corners.
4. Add the above, below and side counts. The supporting floor is not a block.

Common mistake: Assuming that six faces means at most six neighbors. Several smaller face areas may touch the same long face.

Practice tip: Use the same above–below–sides order on every target, then build speed without skipping a face.

The number on a front face marks a whole three-dimensional block. Its back, top and bottom can touch blocks you do not see directly.

1. Find the outer edges of the marked block and follow its full length.
2. Check the layer above, then the layer below. Perpendicular long blocks may each cover only part of the target face.
3. Check the four side faces. Count each other block once; ignore contacts only at edges or corners.
4. Add the above, below and side counts. The supporting floor is not a block.

Common mistake: Counting only neighbors beside the printed number misses contacts farther along the same block.

Practice tip: Use the seams on both visible walls to follow a hidden contact into the stack. Do not invent an unshown hole.

Start with the reference direction and the flight condition. Lift is perpendicular to relative airflow, while weight points toward Earth. An unchanged wing can stall at different airspeeds because loading changes how much lift it must produce.

1. Identify whether the problem describes air-relative motion, ground motion or an angle measured from the horizon.
2. Balance the forces only in directions with no acceleration; in a level banked turn, the vertical part of lift supports weight.
3. Calculate load factor as lift divided by weight. For a fixed weight and configuration, stall speed changes with the square root of load factor.
4. Keep critical angle of attack separate from airspeed: exceeding that angle stalls the wing, even in a fast maneuver.

Common mistake: Treating nose attitude as angle of attack, or treating a published 1 g stall speed as an absolute boundary for every maneuver.

Practice tip: Name the reference and fixed quantities before calculating. For a speed-squared relationship, write the ratio and square it explicitly.

System questions become clearer when you identify the input and follow what it does. Pitot-static instruments use pressure, engines convert fuel energy into work, and propeller governors adjust aerodynamic load. Similar-looking faults can behave differently because a drain or alternate source remains open.

1. Name the system input: total pressure, static pressure, electrical power, hydraulic pressure or mechanical shaft power.
2. Trace the input to the component that displays or uses it; do not substitute a related but different instrument.
3. For a failure question, check every stated opening and energy source before predicting what remains functional.
4. For a regulated system, determine which change opposes the disturbance; for example, a coarser propeller pitch increases load when rpm rises.

Common mistake: Assuming all blocked-pitot cases behave alike, or assuming every electrical device depends on the main aircraft battery.

Practice tip: Draw a short input-to-output chain. Mark what is blocked, what remains open and which independent source still supplies energy.

Weather observations describe conditions at a stated time; forecasts describe expected future conditions. Navigation calculations need ground motion. Heading is where the nose points, while track is the path over the ground after wind has been included.

1. Check whether a weather product is an observation or forecast, then match its time to the planned flight period.
2. For weather mechanisms, follow temperature, moisture and vertical motion rather than assuming one clue guarantees a storm.
3. For a direct headwind, subtract wind speed from true airspeed to obtain groundspeed; divide distance by groundspeed to find time.
4. For a crosswind, aim into the wind so the sideways air-relative motion cancels ground drift. Keep true and magnetic directions on one consistent reference.

Common mistake: Using true airspeed as groundspeed in a wind, confusing the direction wind comes from with the direction it pushes, or treating today’s good observation as a guarantee for later.

Practice tip: Write units and direction labels beside every number. Convert decimal hours by multiplying the fraction by 60, and check product valid times before interpreting weather.