Oman CAA PPL Theory Exam cheat sheet

ICAO Annex 2 (Rules of the Air) requires a VFR flight to remain clear of cloud and in sight of the surface, with flight visibility and distance from cloud set by the State; CAR-Oman mirrors these minima.

In Class C airspace VFR flights require an ATC clearance and continuous two-way radio contact; in Class D they require clearance and radio contact; in Class E only radio contact for IFR; in Class F/G no clearance is required.

Semi-circular rule (below FL 195, non-RVSM): magnetic track 000-179 uses odd thousands (FL 35, 55, 75...); 180-359 uses even thousands (FL 45, 65, 85...). Above FL 195 use FL 300-390 odd/even by track.

VFR flight is not permitted above FL 200 in most States without an instrument rating and a clearance; Oman requires an ATC clearance for all controlled airspace entry.

Aircraft must be operated with a valid Certificate of Airworthiness, Certificate of Registration, and crew licences carried on board; Oman CAR-Oman Part 4 covers personnel licensing.

Right-of-way: converging aircraft of the same category - the one on the right has right-of-way; head-on - both turn right; overtaking - the overtaken aircraft has right-of-way and the overtaking aircraft keeps clear.

Aircraft on final approach or landing have right-of-way over aircraft on the ground or in flight; an aircraft taxiing gives way to aircraft taking off or landing.

The 1:1 rule for take-off minima: a pilot must not commence take-off unless the reported RVR/visibility is at least the applicable take-off minima for the runway and aircraft category.

Position reports to ATC must include aircraft identification, position, time, altitude/flight level, and next position with ETA when requested; Oman AIP ENR 1.1 details reporting points.

Four-stroke cycle: induction, compression, combustion (power), exhaust - one power stroke per two crankshaft revolutions per cylinder.

Mixture ratio: stoichiometric is about 15:1 air-to-fuel by mass; best power is slightly rich (~12.5:1), best economy slightly lean (~16:1).

Carburettor icing is most likely at ambient temperatures between -7 °C and +21 °C with relative humidity above 50%; apply carb heat before reducing power.

Detonation is uncontrolled explosive combustion causing high cylinder pressures and temperatures; pre-ignition is ignition before the spark - both are prevented by correct mixture, power settings, and fuel grade.

Magneto check: with engine at run-up RPM, switch each magneto off in turn; maximum permissible drop is typically 150 RPM (often 175 RPM on some types) and maximum differential between magnetos is 50 RPM.

The electrical system typically comprises a battery, alternator/generator, voltage regulator, bus bar, and circuit breakers; the alternator supplies current in flight and the battery is for starting and emergency supply.

Hydraulic systems use a reservoir, pump, pressure relief valve, selector valves, and actuators; a pressure relief valve protects against overpressure and a thermal relief valve protects against fluid expansion.

The vacuum system drives gyroscopic instruments (attitude indicator, heading indicator, turn coordinator); a vacuum gauge reading outside the green arc indicates pump or filter failure.

Landing gear: nosewheel steering is often via rudder pedals with a limited castoring range; shimmy dampers prevent nosewheel oscillation; brake discs are inspected for wear and overheating.

Density altitude = pressure altitude + 120 × (OAT − ISA temperature at that pressure altitude); performance charts are based on pressure altitude and temperature.

Take-off and landing distances increase with altitude, temperature, mass, tailwind, and upslope; headwind and downslope reduce them.

Rate of climb = (excess power / weight); climb gradient = (excess thrust / weight) - best angle of climb (Vx) maximises height per distance, best rate (Vy) maximises height per time.

Mass and balance: CG must lie within the forward and aft limits; forward CG increases stability and stall speed but reduces performance; aft CG reduces stability and can cause departure from controlled flight.

Fuel planning: trip fuel + contingency (typically 5% of trip fuel or 5 minutes hold) + alternate fuel + final reserve (30 minutes at holding speed for VFR) + taxi fuel.

Endurance = usable fuel / fuel consumption; range = endurance × ground speed; specific range is maximised at the speed for best L/D ratio.

Load factor n = 1/cos(bank angle) in a level turn; stall speed increases by √n - at 60° bank the stall speed increases by about 41%.

For a given mass, the stall speed is proportional to the square root of the load factor and inversely proportional to the square root of the air density ratio.

Hypoxia symptoms: euphoria, impaired judgement, headache, cyanosis, tingling, and loss of consciousness; time of useful consciousness at FL 350 is about 30-60 seconds without oxygen.

Hyperventilation causes dizziness, tingling, and muscle cramps; treatment is to slow the breathing rate or breathe into a bag - do not give oxygen first if hypoxia is suspected.

Spatial disorientation: somatogravic illusion (false climb sensation during acceleration), somatogyral illusion, and the leans - trust the instruments, not sensations.

Ear block (barotrauma) occurs on descent; treatment includes Valsalva, swallowing, or yawning; if unresolved, do not continue descent or fly with a cold.

Alcohol: ICAO recommends no alcohol for 8 hours before flight and blood alcohol below 0.04%; some States apply stricter limits - Oman prohibits flying with any impairment.

Fatigue: circadian low points are around 03:00-06:00 and 15:00-17:00 local; duty and rest limits are set by CAR-Oman Part 8 (Operations).

Carbon monoxide poisoning causes headache, dizziness, and cherry-red skin; it is odourless and undetectable without a detector - suspect it with cabin heat on and symptoms in all occupants.

Stress and workload: performance is optimal at moderate arousal (Yerkes-Dodson law); high workload narrows attention and increases error rates - use checklists and prioritise aviate, navigate, communicate.

ISA: sea-level temperature 15 °C, pressure 1013.25 hPa, lapse rate 1.98 °C per 1,000 ft up to 36,090 ft (tropopause).

QNH is the pressure setting that makes the altimeter read elevation when on the ground; QFE makes it read zero at the reference point; QNE (1013.25 hPa) is used above the transition altitude.

The 1 in 60 rule: an error of 1 NM off track over 60 NM corresponds to a 1° track error; use it for mental drift corrections.

Cloud types: cumulonimbus (CB) produces thunderstorms, icing, hail, and severe turbulence; avoid by at least 20 NM; the tropopause limits vertical development.

Icing: clear ice forms in large supercooled droplets at 0 to -10 °C; rime ice forms in small droplets at -10 to -20 °C; both increase weight and drag and reduce lift.

Wind: surface friction causes the wind to back and decrease in speed near the surface; in the northern hemisphere wind veers with altitude (Ekman spiral).

Sea breeze blows from sea to land by day; land breeze blows from land to sea by night; both are driven by differential heating.

Temperature/dewpoint spread: a spread of 2 °C or less with cooling after sunset favours fog or mist formation; radiation fog forms on clear, calm nights.

Thunderstorm life cycle: cumulus stage (updrafts only), mature stage (updrafts and downdrafts, heaviest rain, lightning, hail), dissipating stage (downdrafts dominate).

True course (TC) + wind correction angle = true heading (TH); TH + variation (east subtract, west add) = magnetic heading (MH); MH + deviation = compass heading (CH).

Variation is the angle between true north and magnetic north and is shown on the chart; deviation is the error of the compass on that aircraft and is shown on the compass card.

Track made good (TMG) = TC + drift; drift = angle between heading and track; use the 1 in 60 rule to estimate drift.

Great circle: shortest distance between two points on a sphere; rhumb line: constant track; on a Mercator chart great circles appear as curved lines and rhumb lines as straight lines.

Time = distance / ground speed; ground speed = true airspeed ± wind component along track; use the wind triangle or the CRP-1 flight computer.

VOR: radial indicated is magnetic; TO/FROM flag indicates whether the selected course takes you to or from the station; CDI centres when on the selected radial.

NDB/ADF: the needle points to the station relative to the aircraft heading; relative bearing + heading = magnetic bearing to the station (QDM).

GPS: position accuracy depends on satellite geometry (HDOP); RAIM predicts whether enough satellites are available for integrity monitoring; the receiver outputs track and groundspeed.

Dead reckoning: maintain a navigation log with heading, time, fuel, and position at each turning point; compare ETA with actual time and revise.

Pre-flight: check weather, NOTAMs, aircraft documents, mass and balance, fuel, and performance; complete a walk-around and check fuel drains for water and sediment.

Emergency: aviate, navigate, communicate; declare an emergency with MAYDAY (distress) or PAN-PAN (urgency) and state position, altitude, heading, and intentions.

Engine failure after take-off: lower the nose to maintain best glide speed, select a landing area within gliding range, attempt restart per checklist, and only turn back if altitude and terrain allow.

Fire in flight: shut off fuel and electrical supply to the affected engine, use the fire extinguisher, and land as soon as possible; do not restart an engine that has been on fire.

Ditching: transmit MAYDAY with position, set transponder to 7700, land into wind with minimum speed, and evacuate after the aircraft stops.

Wake turbulence: generated by wingtip vortices; avoid by taking off before the preceding aircraft's rotation point, landing after its touchdown point, and staying upwind and above its flight path.

Runway incursion prevention: read back all clearances, hold short of marked holding positions, and use sterile cockpit procedures during taxi and take-off.

Security: unlawful interference code 7500, radio failure code 7600, emergency code 7700; radio failure in VFR continues under VFR and lands at the nearest suitable aerodrome.

Lift L = ½ρV²SCL; drag D = ½ρV²SCD; induced drag decreases with speed while parasite drag increases with the square of speed.

Total drag is minimum at the speed for best L/D ratio, which is also the speed for maximum glide range (engine off) and best endurance for a propeller aircraft.

Stall occurs when the critical angle of attack is exceeded (typically 15-18°); the stall speed increases with mass, load factor, and forward CG, and decreases with altitude (IAS).

Bernoulli and Newton: lift results from pressure difference and downward momentum change; the centre of pressure moves forward as angle of attack increases up to the stall.

Longitudinal stability requires the CG forward of the neutral point; the horizontal stabiliser provides a downward force that increases with forward CG, increasing trim drag.

Adverse yaw: the downgoing wing has more induced drag, yawing the aircraft away from the turn; coordinated with rudder and aileron.

Load factor: in a level turn n = 1/cos φ; the stall speed increases with √n; the manoeuvring speed VA is the speed above which full deflection of a single control could exceed the limit load.

Flaps increase lift and drag and lower the stall speed; they also shift the centre of pressure and can cause a pitch change when extended.

Standard call: station called, aircraft identification, position, altitude, and intentions - e.g. "Muscat Tower, A4C, Cessna 172, 5 miles south, 2,500 ft, inbound to land."

Read back: clearances, runway assignments, hold-short instructions, altimeter settings, and frequency changes must be read back.

Phonetic alphabet: Alpha, Bravo, Charlie, Delta, Echo, Foxtrot, Golf, Hotel, India, Juliett, Kilo, Lima, Mike, November, Oscar, Papa, Quebec, Romeo, Sierra, Tango, Uniform, Victor, Whiskey, X-ray, Yankee, Zulu.

Numbers: transmit digits individually, e.g. 2,500 as "two five zero zero"; flight levels as "FL two five zero"; headings as "heading zero niner zero".

MAYDAY (distress) is repeated three times and has absolute priority; PAN-PAN (urgency) is repeated three times and indicates a serious but non-immediate situation.

Frequency: 121.5 MHz is the emergency frequency; 123.45 MHz is for air-to-air; listen before transmitting and use the correct phraseology from ICAO Doc 9432.

Transponder: squawk 7700 for emergency, 7600 for radio failure, 7500 for unlawful interference; Mode C reports pressure altitude.

Radio failure in VFR: continue under VFR, remain clear of controlled airspace unless previously cleared, land at the nearest suitable aerodrome, and report arrival by telephone.

Opening call: "[Station], [Aircraft callsign], [type], [position], [altitude], [intentions]" - speak slowly and clearly, and use standard phraseology.

Clearance read-back must include the aircraft callsign, clearance limit, route, altitude, and any frequency or squawk - read back exactly as issued.

Departure call: "[Tower], [callsign], ready for departure, runway [number]" - wait for the take-off clearance before entering the runway.

Position report: "[Station], [callsign], [position], [time], [altitude], [next position] at [time]" - use the 24-hour clock.

Emergency: "MAYDAY MAYDAY MAYDAY, [Station], [callsign], [nature of emergency], [position], [altitude], [heading], [intentions]" - then follow ATC instructions.

Radio discipline: use standard phrases (ROGER, WILCO, AFFIRM, NEGATIVE, STANDBY, SAY AGAIN, CORRECTION); do not use CB slang; keep transmissions short.

Frequency change: "[Station], [callsign], changing to [frequency]" - acknowledge and switch only after the instruction is read back.

Arrival: request joining instructions, report position and altitude, and read back the landing clearance including runway and wind.

Altimeter: an aneroid barometer calibrated to ISA; set QNH for altitude above mean sea level, QFE for height above the reference, QNE (1013.25 hPa) above the transition altitude.

Airspeed indicator: measures dynamic pressure; IAS + position error = CAS; CAS + compressibility = EAS; EAS + density error = TAS.

Vertical speed indicator: rate of change of static pressure; it lags and must be checked for zero before flight; a stuck VSI indicates a blocked static source.

Attitude indicator: gyroscope with two degrees of freedom; it is erect and reliable after spin-up but can tumble and must be caged/uncaged; it is not affected by bank limits if air-driven.

Heading indicator: directional gyro with a horizontal spin axis; it drifts due to earth rotation and friction and must be realigned with the magnetic compass every 10-15 minutes.

Turn coordinator: shows rate of turn and bank; a standard rate turn is 3°/second (2 minutes for 360°); the slip/skid ball shows coordination.

Magnetic compass: turns and acceleration errors; it is most reliable in straight and level flight; use the compass correction card for deviation.

Engine instruments: tachometer (RPM), oil pressure and temperature, fuel quantity and flow, cylinder head temperature, and exhaust gas temperature - EGT peaks at best power mixture.