Cheat sheet

400 feet AGL, and the only exception

AGL

above the ground beneath the aircraft, never MSL — sloping terrain needs continuous re-reference

immediate uppermost limit

the topmost point of the one structure being orbited, antennas and appurtenances included

Both conditions are conjunctive and continuous, so it is a cylinder and not a dome: beside a 1,000-ft tower the ceiling is 1,400 ft AGL only while the aircraft stays inside a 400-ft lateral radius, and stepping out to 500 ft collapses it to 400 ft without the aircraft changing altitude.

The exception raises the altitude limit and nothing else — it grants no airspace access. All of §107.51 is waivable under §107.205(i), so the classic answer that the 400-ft limit cannot be waived is false.

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87 knots and 3 statute miles

flight visibility

the average slant distance from the control station at which prominent unlighted objects are seen by day and prominent lighted objects by night

87 knots is one limit stated in two units, and it is groundspeed: a tailwind can push a slow-airspeed aircraft over it even though the airframe never exceeds its own airspeed limit.

Visibility is statute, never nautical, and it is measured at the control station rather than at the reporting station — so a pilot 15 miles from a fogged-in field is not bound by that field's number, but must then establish 3 SM by other reliable means.

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Cloud clearance, and the altitude it leaves

Part 107 has one cloud rule in every class of airspace and there is no “above the cloud” figure at all; the 1,000 above / 500 below / 2,000 horizontal matrix belongs to §91.155 and is the standing distractor. Nor is there any Class B clear-of-clouds relief.

§107.51(d) says clouds, not ceiling, so a scattered layer counts. OVC008 leaves 300 ft AGL; a 1,500-ft SCT layer leaves the 400-ft cap binding but still demands 2,000 ft laterally; VV002 leaves no legal altitude at all.

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55 pounds and 0.55 pounds

Less than 55 excludes 55.0 exactly, and the test is takeoff weight with battery, camera, gimbal, guards, tape, strobes and payload all counted: a 54-lb airframe with a 2-lb camera is not a small unmanned aircraft.

0.55 lb exempts nothing under part 107. The §48.15(b) registration floor is conjunctive — 0.55 lb or less and operated exclusively under 49 U.S.C. 44809 — so a 240-gram aircraft flown for compensation must still be registered.

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The four operations-over-people categories

11 and 25 foot-pounds are injury-severity equivalence standards established by the manufacturer through an accepted means of compliance, not energies the remote pilot measures; the pilot verifies the declaration-of-compliance listing and the label. Category 1 needs neither.

Category 3 alone carries a flat ban on open-air assemblies. Over occupied moving vehicles §107.145 collapses Categories 1, 2 and 3 into the same restriction, and only Category 4 may sustain flight over them outside a closed or restricted-access site.

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Anti-collision lighting and civil twilight

The light is required at night and during civil twilight, and may be reduced in intensity but never extinguished. Its 3 statute miles is outward visibility of the light — a different figure from §107.51(c)'s 3 SM of flight visibility measured at the control station.

Outside Alaska civil twilight is a fixed 30 minutes, not the astronomical 6° below the horizon; Alaska uses the Air Almanac. §107.205(b) waives only the lighting in §107.29(a)(2) and (b), never the §107.29(a)(1) training, and night flight itself has needed no waiver since April 21, 2021.

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Every clock and fee in one place

Ten calendar days runs from the operation, not from discovery of the damage or from the repair estimate. The §107.21 emergency-deviation report is a separate instrument: it is due only upon request of the Administrator and carries no deadline at all.

Part 107 registration is per aircraft; the one-certificate-covers-everything registration is §48.105 and is recreational only, and a registration cannot be transferred between operation types. Remote ID has bound operators since September 16, 2023 — March 16, 2024 ended only an enforcement-discretion policy.

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The two $500 tests

Two independent escape hatches, applied as whichever figure is lower: a $200 mailbox that costs $600 to repair is not reportable, and $200 of damage to a $600 gate is not reportable. Exactly $500 does not exceed $500, so it is not reportable either.

Damage to the small unmanned aircraft itself never counts. The NTSB duty under 49 CFR part 830 is immediate and additive — filing with the FAA does not satisfy it, and its weight and damage triggers are NTSB numbers rather than part 107 numbers.

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The UAG knowledge test

A candidate answers 65 items but is scored on 60, and the 70% applies only to the scored ones. Current weights come from the PSI bulletin effective September 29, 2025 — Regulations 48%, Operations 25%, Airspace 20%, Weather 5%, Loading and Performance 2% — and the FAA has stated in writing that the ACS Appendix 1 table is obsolete.

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The age split, and eligibility

There is no medical certificate anywhere in part 107: §107.61(c) and §107.17 are pure self-assessment, with no form, exam or interval. The English requirement is not absolute — where the shortfall is medical the FAA may issue the certificate with operating limitations.

The split works because the report lasts 24 calendar months, so a 14-year-old can pass and still hold a usable report at 16.

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From score report to plastic card

PSI validates only the FAA Tracking Number and the first and last name as entered in IACRA, so a name mismatch is fixed in IACRA and not at the test centre. The Exam ID can take up to 48 hours to appear.

The 120-day temporary certificate, the 24-month report validity and the 24-month recency window are three different clocks and are routinely offered as one another's distractors.

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Recency and the recurrent courses

The certificate itself never expires; only the privilege of acting as remote pilot in command lapses, and it is restored by a free online course with no test, no application and no fee. A pilot whose recency has lapsed may still fly under the direct supervision of a current remote PIC.

The proctored UGR recurrent test was withdrawn on April 6, 2021, and recurrent training completed before that date does not satisfy the night prerequisite in §107.29(a)(1).

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The part 61 route, and thirteen areas versus eight

The part 61 route needs all three things: the certificate, flight-review currency, and §107.74 training. Its application is submitted in person to a FSDO, DPE, ACR or CFI, who verifies identity and endorses the flight review — and a CFI cannot issue a temporary certificate, so a pilot who wants to fly at once uses one of the other three.

Knowledge-test applicants use none of that machinery: they file through IACRA with no endorsement and no identity verification step.

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Bars, and keeping the paperwork straight

The §107.69 bar is not discretionary and reaches any certificate, rating, authorization or test issued under the whole chapter — including for the person who merely supplied the questions. The §§107.57 and 107.59 periods are “up to” a year and run from the final conviction, the act, or the refusal, never from the application.

A voluntarily surrendered certificate is not reissued unless the holder completes §§107.61 and 107.63 again, and §107.7 requires the certificate and identification in physical possession and readily accessible, producible on request from the Administrator, the NTSB, any Federal, State or local law enforcement officer, or the TSA.

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Class dimensions

Class C and D ceilings are defined above the airport elevation but charted in MSL, so the field elevation in the airport data block is the one number that converts a charted floor into AGL.

Class A is not depicted on a visual chart and is unreachable under a 400-ft limit, which is why it is absent from §107.41. Class G is never drawn either — it is deduced as everything left over.

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Where §107.41 bites

All Class E does not require authorization. A 700-ft or 1,200-ft AGL transition-area floor leaves Class G beneath it, so a flight below 400 ft AGL there needs nothing; those vignettes are identification questions, not authorization questions.

A surface-area arrival extension becomes part of the surface area and is in effect during the same hours, so it does require authorization. Part-time Class D or Class E surface areas change the answer by time of day — the chart says to see NOTAMs or the Chart Supplement for the effective hours.

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Class C’s two radii, and the Mode C veil

Ten and twenty nautical miles are different objects. The 10 NM shelf is charted airspace and triggers §107.41; the 20 NM Outer Area is an uncharted service volume and triggers nothing. A question that uses the words “outer area” wants 20 NM.

The Mode C veil is a transponder and ADS-B Out equipment rule for manned aircraft and imposes no part 107 duty — §§107.52 and 107.53 in fact prohibit a small UAS from operating with a transponder on or ADS-B Out transmitting.

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Getting the authorization

A UAS Facility Map is a job aid, not a clearance. Its grid value is AGL and is the most an FAA processor may approve without further coordination; a 0 grid is not a permanent no-fly zone, it just forces a further-coordination request. Grids are 30 seconds of latitude by 30 seconds of longitude, about 0.25 square mile or 160 acres, and update on the 56-day chart cycle.

LAANC buys airspace access only: NOTAMs, weather, TFRs, special use airspace and §99.7 restrictions all still apply, the pilot need not call the tower unless the authorization says so, and no authorization can exceed 400 ft AGL without a separate §107.51 waiver.

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Authorization versus waiver, and the ten waivable rules

An authorization is permission to enter airspace that §107.41 otherwise closes, and the rule stays intact; a waiver is a certificate permitting deviation from one of those ten rules. Everything absent from the list is unwaivable — §§107.9, 107.12, 107.15, 107.19, 107.23, 107.27, 107.36, 107.37(b), 107.43, 107.45, 107.47, 107.49, and all of subparts C, D and E. Hazmat relief would need a part 11 exemption, not a waiver.

All of §107.51 is waivable, altitude included. But §107.205(a) and (c) carry the same express carve-out: no waiver of operation from a moving vehicle or of visual line of sight will be issued to allow the carriage of another person's property for compensation or hire.

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Line style and colour

Colour on an airspace line encodes class; colour on an airport symbol encodes tower status only. The two confusable magentas are the dashed line, which is a Class E surface area and needs §107.41 authorization, and the soft-edged vignette, which is a 700-ft AGL floor and does not.

Only airspace below 18,000 ft MSL is drawn, and part-time status is shown by a boxed note rather than by a different line style.

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The altitude box

Every charted altitude is MSL while every part 107 limit is AGL, and the field elevation in the airport data block is the only bridge between them. 110 over 70 in blue is a Class B shelf from 7,000 to 11,000 ft MSL; 40 over SFC in magenta is Class C from the surface to 4,000 ft MSL.

A plus sign means operations at and below that altitude are outside the Class B; a minus sign means the ceiling is exclusive. Blue figures are Class B, magenta Class C, solid black a TRSA sector.

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Vignettes

Under a magenta vignette the layer from the surface to 700 ft AGL is Class G, so a flight below 400 ft AGL there needs no authorization; outside every vignette Class G runs to 14,500 ft MSL.

“Zipper” is not Chart Users' Guide language and a candidate hunting for it in the legend will not find it — the FAA says vignette, or a symbol and a number indicating the floor.

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Airport symbol and data block

Runway length rounds at 70, so 8,069 ft charts as 80 and 8,070 ft charts as 81, and a missing element is replaced by a dash rather than dropped. A plain circle with no runway pattern is a soft-surfaced or sub-1,500-ft field with no fuel.

A star on the symbol itself is a rotating beacon operating dusk to dawn; a star after the tower frequency means the tower is part time. A blue symbol can sit inside Class B, C or D, and a magenta one can sit inside a dashed-magenta Class E surface area that still needs authorization.

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Obstruction heights

The parenthesised AGL figure governs the 400-ft limit and the structure exception; the MSL figure is the one to compare against a charted airspace floor. Reaching for the MSL number to compute a 400-ft ceiling is the standing error.

Nothing at or below 200 ft AGL (299 ft inside yellow city tint) is charted at all, and a group symbol shows only the tallest member, so the absence of an obstruction symbol proves nothing about what is there.

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Maximum Elevation Figure, and scale

An MEF is a rounded-up MSL maximum carrying built-in error and obstacle allowances and it is not verified by field survey: it is not AGL, not a clearance altitude, and subtracting terrain elevation from it does not produce a legal part 107 ceiling.

Measure distance with the margin scale bar or by counting one-minute latitude ticks up the vertical graticule — a minute of longitude is shorter than a nautical mile everywhere except the equator, about 0.7 NM at 45° N.

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TFR footprints

The §91.137 exceptions are graduated: (a)(1) has exactly one, (a)(2) five, (a)(3) four — and ATC may authorize entry on its own authority only under (a)(2) and (a)(3). None of the categories maps onto a routine part 107 job, so the realistic path in is a Special Governmental Interest authorization.

Presidential TFRs name unmanned aircraft systems expressly, admit no loitering even in the outer ring, and classify the airspace as national defense airspace. §91.143 has no participation exception at all — ATC authorization is the only relief.

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The standing stadium restriction

Because its authority is §99.7 rather than §91.145 it is permanent, needs no 30-day notice and generates no per-game NOTAM, so it will not appear on the TFR list on the day — use SEAMS or B4UFLY. Relief exists only for event, venue and rights-holder broadcast flights with an approved airspace waiver.

The three details most often missed: the seating floor is 30,000, NCAA football must be Division One, and qualifying and pre-race events are not covered. College basketball, the NHL, the NBA and MLS are not on the list.

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§99.7 and the national security restrictions

These are facility-shaped rather than circular and are commonly absent from a paper sectional; the covered locations live on the UAS Data Display System and in B4UFLY. Their 400-ft ceiling coincides exactly with §107.51(b), so they are effectively total prohibitions for a part 107 operator.

§99.7 is special security instructions, not ADIZ position reporting. The DC FRZ is absolute for unmanned aircraft absent an airspace waiver, and it is a smaller irregular zone inside the 15-mile inner ring, not the ring itself.

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Special use airspace, and who can actually stop you

A restricted area needs permission whether or not it is active, and a LAANC authorization does nothing for one. Controlled firing areas are never charted because activity is suspended the moment an aircraft may be approaching.

The margin tabulation carries the altitudes, times of use and controlling agency — and no activation NOTAM is issued for permanently listed times of use. A National Security Area's broken magenta line is a request to avoid, not a prohibition.

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NOTAMs and the publication cycles

Sectionals run on 56 days; the 28-day figure belongs to the NTAP and the IFR approach-chart midcycle change notice. Airway, procedural, open-duration special security instruction and SFRA notices are briefed solely on pilot request.

A NOTAM date-time group is UTC, so 2609141530-2609142145 means 14 September 2026 from 1530Z to 2145Z, and -PERM means permanent. Read the units: NMR is nautical miles, and SFC-17999FT MSL is not AGL.

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METAR body groups, and what silence means

When an element does not occur or cannot be observed the group is omitted rather than zero-filled, so parse by pattern — find the SM, the R…FT, the A####. AUTO means fully automated with no human oversight; an augmented report carries no AUTO, and COR replaces AUTO on a correction.

An automated station reports cloud only up to 12,000 ft, so CLR is a statement about sensor range. AWOS issues a METAR every 20 minutes and never a SPECI, cloud is a 30-minute average and everything else a 10-minute one, and the local voice broadcast gives magnetic wind while the network METAR gives true.

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The wind group

METAR, TAF and FB winds are all referenced to true north. Only a PIREP's /WV and the ASOS or AWOS local voice broadcast are magnetic — and a runway number is magnetic, so a forecast wind must be corrected for variation before it is matched to a runway.

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Visibility, RVR, and the two letters

M means two different things: “less than” in visibility and RVR, and “minus” in the temperature group — M1/4SM is a quarter mile while 04/M02 is +4 °C with a −2 °C dewpoint. The altimeter drops the decimal point, so A2992 is 29.92 inHg.

RVR increments are 100 ft to 1,000, 200 ft from 1,000 to 3,000 and 500 ft from 3,000 to 6,000, which is why 2,600 is a legal value and 2,650 is not.

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Sky cover in eighths, and the ceiling

FEW and SCT are never ceilings, but they are still clouds, so §107.51(d)'s 500 ft below and 2,000 ft horizontally apply to them. In FEW012 SCT030 BKN050 the ceiling is 5,000 ft AGL while the layer that actually binds a part 107 flight is the one at 1,200 ft.

SKC is used at manual stations and CLR at automated ones when nothing is detected at or below 12,000 ft. VV001 is an indefinite ceiling with 100 ft of vertical visibility, and it is worse than a 100-ft cloud base because slant-range visibility is gone.

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The flight categories

The definitions are “and/or”, so the category reported is the worse of the ceiling-derived and visibility-derived answers, and the MVFR bounds are inclusive at both ends.

They are situational-awareness labels only: there are no part 91 MVFR minimums, and §107.51(c)'s 3 SM floor sits exactly at the bottom of MVFR, so an MVFR field reporting 3 SM is right at the part 107 limit.

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TAF

A TAF carries no temperature group and never uses 10SM; a METAR never uses P6SM. An FM group is complete and supersedes everything before it, while a TEMPO group lists only the elements that change, so unlisted elements carry over from the prevailing line.

PROB30 is the only PROB group the NWS uses domestically — PROB40 is military and international. A new or amended TAF cancels the previous one immediately; do not wait for the start of its valid period.

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FB winds and temperatures aloft

Any first pair from 51 to 86 is a coded direction for a wind of 100 kt or more, while 99 in the first pair is the light-and-variable flag and not a direction at all.

No wind is forecast within 1,500 ft of station elevation and no temperature within 2,500 ft, which is why the 3,000-ft level almost always carries a wind and no temperature.

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PIREP

PIREP altitudes are MSL while METAR and TAF cloud heights are AGL, and /WV is the one wind in the system referenced to magnetic north. /OV is where the phenomenon was, not where the aircraft was when the report was filed.

Severe or extreme turbulence, severe icing, tornadoes, funnel clouds, hail, volcanic ash and low-level wind shear within 2,000 ft of the surface make the report urgent; light rime icing and light turbulence do not. Icing and turbulence reports always include the aircraft type.

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AIRMET, SIGMET and Convective SIGMET

Validity runs the opposite way to severity: Convective SIGMET 2 hours, issued hourly at 55 minutes past; SIGMET up to 4 hours; AIRMET 6 hours, and 8 in Alaska. All of them are issued to all pilots and need not be requested.

Any Convective SIGMET already implies severe or greater turbulence, severe icing and low-level wind shear, so no separate SIGMET is issued for those near CONUS thunderstorms. Its polygon is a snapshot at H+55, not a forecast of where the cells will be at the end of the hour.

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The standard atmosphere

3.5 is the Fahrenheit figure and 2 is the Celsius figure; mixing them puts the ISA temperature out by about three quarters. The 6.5 °C rate is per 1,000 metres, not per 1,000 feet.

Each lapse rate stops where the handbook stops it — pressure at 10,000 ft, temperature at 36,000 ft — and writing 1013.2 inHg or 29.92 mb is a pure unit transposition the exam offers as an answer.

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Three lapse rates, and stability

The adiabatic rates describe a moving parcel; the standard rate describes the column, so using 3 °C per 1,000 ft as the environmental rate is a category error. Stability is inverse to lapse rate — daytime surface heating steepens the lapse rate and decreases stability, while nighttime cooling and subsidence increase it.

Stable air gives stratiform cloud, steady precipitation, drizzle, smooth air and poor surface visibility; unstable air gives cumuliform cloud, showers, turbulence and good surface visibility. The visibility half of that pairing is the half candidates reverse.

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Inversions and turbulence

The shear sits across the top of an inversion, not inside it, so a dawn launch climbs out of smooth air into a sharp wind change — in mountainous terrain the inversion top can sit at 900 to 1,000 ft AGL, just above the part 107 band.

The FAA publishes no downwind distance for obstruction turbulence: the widely taught rule that disturbed air extends 10 to 20 times the height of the obstruction appears in no FAA publication. What it publishes is the four dependencies plus the counterintuitive point that stable air makes smaller eddies that dissipate slowly and therefore persist farther downwind.

Wind aloft is stronger and turned: at 2,000 ft AGL it runs 20° to 40° right of the surface wind and faster. The FAA publishes no wind-gradient profile and no sUAS wind limit at all — wind limits are the manufacturer's, and §107.51(a)'s 87 knots is a groundspeed cap.

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Cloud base from temperature and dew point

T

reported surface temperature, °F

DP

reported surface dew point, °F

The answer is AGL: do not add field elevation and report it as MSL. Use 4.4 with Fahrenheit inputs — the Celsius convergence is 2.5 °C per 1,000 ft — keep the × 1,000 step, and do not round to the nearest hundred.

Fog seldom forms once the temperature-dewpoint spread exceeds 2 °C (4 °F), and a rising unsaturated parcel closes the spread while a descending one opens it.

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Fog

A calm, clear, cool inland morning after rain soaked the ground is radiation fog, not advection fog — advection fog requires wind. Steam fog is cold air over warm water; advection fog is warm air over a cold surface.

Radiation fog less than 20 feet thick is ground fog and burns off rapidly after sunrise, but upslope and advection fog may not burn off with the morning sun and can persist for days.

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Thunderstorms and microbursts

The mature stage is the most violent, not the cumulus stage, and the third ingredient is an unstable lapse rate rather than warm or cold air. A gust front can arrive up to 15 miles ahead of the precipitation under clear-looking sky, which is precisely the hazard at 400 ft AGL.

The microburst's 1,000 ft is a depth and not a diameter, and it exceeds the whole part 107 altitude envelope, so there is no altitude to escape into. The only visible clue may be virga or a ring of blowing dust — a dry microburst gives no rain cue at all.

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Fronts and icing

Name the front by the advancing air, not by the air it replaces, and expect an occluded front to bring warm-front weather immediately followed by cold-front weather rather than something mild.

Icing needs the temperature to approach 0 °C, not to be below freezing, and the worst band is 0 to −10 °C. Rime is rough, milky and opaque from small droplets; clear ice is glossy, from large droplets, and more hazardous. Frost on the blades reduces lift and increases drag and must be removed before flight.

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Density altitude, as the FAA actually gives it

The FAA publishes no per-degree correction: the 120 ft/°C rule appears in no FAA document, and the FAA's own worked examples imply about 112 ft/°C on the hot side and 127 ft/°C on the cold side. It also never writes (29.92 − setting) × 1,000 — its own field-elevation-versus-pressure table works out to roughly 935 ft per inch of mercury, so an altimeter setting of 29.00 is worth +863 ft, not +920 ft, and 30.00 is worth −73 ft.

High density altitude means low air density, not high. Moist air is less dense than dry air, so humidity raises density altitude. Thin air cuts power, thrust and lift together, and the FAA's advice for a high, hot, humid site is to reduce weight before flight is attempted.

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Datum, arm, moment and CG

datum

an imaginary vertical plane established by the manufacturer, from which every arm is measured

arm

the horizontal distance from the datum to the item's own centre of gravity, in inches

CG range

the band between the forward and aft limits, which the loaded CG must fall inside

Weight and CG are two independent tests: an aircraft can sit inside its maximum gross takeoff weight and outside its CG range at the same time, and both must pass. A datum placed ahead of the aircraft makes every arm positive and minimises sign errors.

CG limits come from the Pilot's Operating Handbook or UAS Flight Manual, not from the Aircraft Weight and Balance Handbook — the FAA publishes no sUAS CG example and no sUAS CG envelope. Mixing grams with inches is the commonest silent error.

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Weight shift

Weight moved aft increases the total moment and weight moved forward decreases it, in proportion to the weight moved. What matters is the product of weight and distance, so sliding a light item a long way can beat moving a heavy item a short way.

On a light multirotor the denominator is small, so a small accessory produces a proportionally large CG excursion: 100 g is 3.3% of a 3 kg aircraft's gross weight.

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Ballast

The lever arm is measured from the ballast station to the limit that is out, not to the CG and not to the datum, and the answer must be rounded up because the exact figure lands the CG precisely on the limit.

Ballast is the worst available fix: it spends payload and endurance to buy CG travel, where relocating the offending item costs nothing — and the 55-lb ceiling caps how much ballast can be added at all.

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The load factor chart

n

load factor — the ratio of the load the structure carries to the weight of the aircraft; 3 means three times its weight

For a given bank angle in a level turn the load factor is the same regardless of weight or airspeed, because the rate of turn changes to compensate. A 33-lb airplane in a 30° bank loads its structure to 33 × 1.154 = 38 lb, and beyond 60° another 10° of bank adds roughly another 1 G.

The 80° row is left off deliberately: the testing supplement prints 5.747 while both handbooks print 5.76, so no single key is defensible there. The FAA also publishes no limit load factor for a small unmanned aircraft — 3.8, 4.4 and 6.0 are part 23 manned certification categories.

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Stall speed and load factor

It is the square root, never linear: 4 G doubles the stall speed, it does not quadruple it, and 9 G triples it.

The stall itself is an angle-of-attack event. A given aircraft always stalls at the same angle of attack regardless of airspeed, weight, load factor or density altitude, so speed alone is not a reliable way to avoid one — and a multirotor has no wing and no aerodynamic stall at all.

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Out of limits, forward and aft

Aft is the more dangerous direction because the aircraft loses stability rather than control authority, and designers place the CG slightly forward of the centre of lift for exactly that reason.

Stability about the lateral axis is called longitudinal stability, and the lateral axis is the pitch axis. Static stability is the initial tendency and dynamic stability the response over time, and the two can point opposite ways — positive static with negative dynamic is divergent oscillation.

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Overload and performance

That is the ten-item sUAS list; the handbook's eleventh item, excessive weight on the nose or tail wheel, is dropped for unmanned aircraft. A published maximum gross takeoff weight is not always flyable — high elevation, high temperature and high humidity may require a reduction in weight before flight is attempted.

§107.49 makes it a preflight duty: ensure there is enough available power for the intended operational time, and ensure any object attached or carried is secure and does not adversely affect flight characteristics or controllability. No percentage reserve is named anywhere, and the FAA nowhere quantifies overload penalties for sUAS.

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Zulu time

Four steps: pick the zone offset, subtract an hour if daylight time is in effect, add for local to UTC or subtract for UTC to local, then roll the date if you cross 0000. Atlanta at 2100 local on 3 December is 0200Z on 4 December — the Zulu date is a day later.

Denver at 1600 local in July is 2200Z, because Mountain daylight time is +6 rather than +7. Most of Arizona and all of Hawaii stay on standard time year round, so the daylight note never applies there.

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Runway numbering and selection

θ

the angle between the reported wind direction and the runway heading

Runway 09 spans roughly 085° to 094° magnetic, so a runway number is a rounded azimuth and not a heading. Wind 260 at 12 on a 09/27 field gives runway 27 a 10° offset and an 11.8-kt headwind, so traffic uses 27 and — with no RP notation — the downwind lies south of the field.

Runway numbers and ATC or AWOS reported winds are magnetic, while TAF and FB winds are true, so a forecast wind must be corrected for variation before it is matched to a runway.

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Traffic pattern

Right traffic is never charted at an airport with a full-time control tower, and an RP note sends the reader to the Chart Supplement for the special conditions behind it.

Because part 107 caps the aircraft at 400 ft while propeller patterns are flown at 1,000 ft, the conflict is on final and initial departure within a mile or two of the runway ends — and §107.43 is broken by interference alone: a drone hovering 200 ft over a runway that merely delays a takeoff violates it without violating §107.37(a).

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Beacons, wind indicators and the segmented circle

A tetrahedron shows landing direction and the AIM cautions twice against reading it as a wind indicator; tower instructions supersede it. Green alone or yellow alone appears only alongside a white-and-green or white-and-yellow display.

A beacon operating by day only “often indicates” visibility below 3 miles or a ceiling below 1,000 ft, and only inside a Class B, C, D or surface Class E area — pilots may not rely on it, and there is no regulatory requirement for daylight operation.

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Phonetic alphabet and numbers

4,500 is “four thousand five hundred” but 12,000 is “one two thousand”, never “twelve thousand”. Applying the round-number rule above 9,900 is the reliable error.

Note the FAA's own spellings — Alfa, Juliett, Xray — and that 122.9 is “one two two point niner”, because the FAA says POINT where ICAO says DECIMAL.

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CTAF, UNICOM and MULTICOM

122.9 is not the general CTAF; it is MULTICOM, correct only when nothing at all is on the field. If a UNICOM is published, that published frequency is the CTAF.

Unmanned aircraft are not required to maintain radio communications, and the ACS frames CTAF as a frequency to monitor. The AIM warns that a remote pilot's use of an aviation frequency may violate FCC rules and tells small UAS operators not to contact ATC directly for airspace access.

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The five hazardous attitudes and their antidotes

Two antidotes are two sentences and the exam tests them whole: “Follow the rules” alone and “I can make a difference” alone are the trimmed distractors. Recognise the thought, label it hazardous, then state the antidote.

Impulsivity acts without thinking; macho acts to impress. Invulnerability accepts that accidents happen but never to oneself, and resignation goes along with an unreasonable request rather than deciding.

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DECIDE, 3P, PAVE, CARE and TEAM

Step four of DECIDE is Identify solutions, not identify the problem — the problem was detected at step one. A hazard is a present condition and risk is the future impact of a hazard left uncontrolled: a nick in a propeller blade is the hazard, blade fracture is the risk.

A client waiting on site who has paid for the day is an External pressure under PAVE. The handbook's 4 × 4 matrix uses Improbable, Remote, Occasional and Probable with levels High, Serious, Medium and Low; Frequent and Avoid belong to AC 107-2A's 5 × 5 grid, not to the handbook.

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IMSAFE and fitness for flight

The four alcohol prohibitions are independent: being under 0.04 does not cure the 8-hour rule, and 0.05 nine hours after the last drink still grounds the flight. §§107.17 and 107.27 bind the visual observer and any direct participant, not only the remote pilot in command, and no medical certificate exists to fall back on.

For any new medication wait at least 48 hours after the first dose, and for one with adverse side effects wait five maximal dosing intervals. The first noticeable effect of dehydration is fatigue, not thirst, and acute fatigue is cured only by rest.

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Visual line of sight, observers and FPV

First person view devices may be used but do not satisfy visual line of sight, and binoculars only momentarily to enhance situational awareness. A visual observer is optional and supplements the requirement, but never extends the remote pilot's own line of sight — all three must retain the capability to see the aircraft, and there is no permitted interval of lost sight.

Losing the ability to tell the aircraft's attitude or direction of flight breaks §107.31 even while its position is still known. §107.35 bars the remote PIC, the person on the controls and the visual observer from being involved with more than one unmanned aircraft at a time, and automation does not change that.

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Batteries, maintenance and the emergency

Water is the cooling agent, not an extinguishing agent, and an intact pack exposed to water is a thermal-runaway risk in the other direction, so a soaked pack is treated as damaged. The FAA publishes no lipo storage voltage or state of charge, no storage temperature and no cycle limit — those figures are the manufacturer's.

Firmware is maintenance by definition, so an outstanding manufacturer-required update leaves the aircraft not in a condition for safe operation under §107.15. Records are recommended rather than required outside Category 4, and no mechanic certificate is involved: the AC names the manufacturer, its specified personnel, the operator, or maintenance personnel familiar with the system.

The FAA publishes no definition of lost link or flyaway and no lost-link or return-to-home procedure. What it publishes is §107.19(c)'s duty to plan for a loss of control for any reason, §107.49(b)'s requirement that contingency procedures be briefed, and one sequence: try to re-establish the link, and if that fails execute the pre-briefed contingency.

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