Oman CAA IR(H) cheat sheet

ICAO Annex 2: an IFR flight must file a flight plan and, unless authorised by the ATC unit, comply with the notified IFR procedures for the route.

Standard separation minima in controlled airspace at and above FL290 (RVSM airspace) is 1000 ft vertical between RVSM-approved aircraft; below FL290 it is 1000 ft in most radar environments.

A clearance is an authorisation to proceed under specified conditions; it does not relieve the pilot-in-command of responsibility for terrain clearance or for compliance with the rules of the air.

Read-back is mandatory for route clearances, hold clearances, runway-in-use, altimeter settings, assigned SSR codes and any clearance requiring verbal confirmation.

Position reporting over compulsory reporting points is required for IFR flights in non-radar procedural airspace; reports contain identification, position, time, altitude and next position with ETA.

IFR flights in Class A airspace require an ATC clearance at all times; VFR is not permitted in Class A airspace.

Helicopter IFR operations require the aircraft and crew to hold the specific approvals and ratings stated in the operator's certificate and the State of Registry's regulations.

In an emergency, a pilot may deviate from ATC clearances and procedures to the extent necessary; ATC must be informed as soon as practicable and a written report may be required.

Standard instrument departure obstacle clearance is based on a minimum climb gradient of 3.3% (approximately 200 ft/NM); higher gradients are published when obstacles require them.

Procedure design gradient (PDG) obstacle clearance assumes the aircraft crosses the departure end of the runway at 35 ft above the surface.

Initial approach segment maximum length is generally 50 NM; intermediate segment should be aligned within 30 degrees of the final approach course and no longer than 10 NM.

Final approach segment begins at the final approach fix or final approach point; obstacle clearance in precision approaches is provided by the precision segment surfaces, not by the 300 ft/MNM rule.

Minimum stabilisation concept: the aircraft must be on the correct track, in landing configuration, at final approach speed and with a stable descent rate by 1000 ft AAL in IMC.

A missed approach must be initiated at or before the missed approach point; the published missed approach procedure protects obstacle clearance from the MAPt onward.

Circling approach minima depend on aircraft category; helicopter circling minima are published for Category A and may be lower than for fixed-wing categories.

Decision altitude/height is referenced to the published barometric minimum; a missed approach must be executed if the required visual reference is not established at DA/DH.

VOR radial selection: the CDI needle centres when the selected OBS matches the radial on which the aircraft lies; TO/FROM indicates whether the selected course leads to or from the station.

ILS localiser provides lateral guidance; glideslope provides vertical guidance. The glideslope is usable only within the published localiser course sector and within the glideslope coverage limits.

DME provides slant range distance; at high altitude the slant range error over the station can be significant, so DME distance is not equal to ground distance.

NDB/ADF bearings are subject to night effect, coastal refraction, thunderstorm static and mountain effect; ADF is not approved as a sole means of navigation for IFR in many States.

GNSS/RNAV (GNSS) approaches use the aircraft's navigation system; RAIM prediction must be checked where required, and baro-VNAV requires a temperature correction at low temperatures.

A transponder Mode C altitude must be referenced to the standard pressure setting (1013.2 hPa) when operating in airspace where the altimeter is set to standard.

An ILS glideslope of 3 degrees gives a descent rate of approximately 300 ft/NM; at 90 kt ground speed this is about 450 ft/min.

Radio altimeter (RA) displays height above terrain directly below the aircraft; it is used for decision height in Category II/III operations and for low-level alerting.

IFR fuel planning typically requires taxi fuel, trip fuel, contingency fuel, alternate fuel, final reserve fuel and, where applicable, additional fuel.

The alternate aerodrome must be selected with weather at or above the published alternate minima at the estimated time of arrival; if no alternate is required, the destination must meet the specified planning minima.

The point of no return (PNR) is the point from which the aircraft can return to the departure aerodrome with the fuel remaining; the equal time point (ETP) is the point from which the time to two aerodromes is equal.

Drift and groundspeed are derived from the wind triangle: heading = track ± drift; groundspeed = TAS adjusted for wind component.

For IFR flight, the flight plan must include the route, altitudes, alternate aerodromes, endurance, persons on board and the aircraft's navigation and communication equipment.

A flight plan must be filed at least 30 minutes before departure for IFR flights unless the ATS unit accepts a shorter notice period.

Fuel monitoring: compare actual fuel consumption with planned consumption at each waypoint; a negative trend requires a decision to divert or return before the final reserve is compromised.

Contingency fuel is normally 5% of trip fuel or 5 minutes holding at 1500 ft above the destination, whichever is greater, unless the operator's approved method states otherwise.

The standard atmosphere at sea level is 1013.25 hPa and 15 degrees C, with a lapse rate of 1.98 degrees C per 1000 ft in the troposphere.

QNH is the altimeter setting that causes the altimeter to read elevation when on the ground; QFE causes it to read zero at the reference point; QNE is the standard setting 1013.2 hPa.

At low temperatures, the true altitude of an aircraft is lower than the indicated altitude when the altimeter is set to QNH; cold-temperature corrections are required for procedure minima.

Icing risk increases in stratiform cloud at temperatures between 0 and -20 degrees C; supercooled large droplets can cause rapid airframe icing.

Thunderstorms contain severe turbulence, hail, lightning and downbursts; IFR flights should avoid cells by at least 20 NM where possible and never penetrate a cumulonimbus.

Mountain wave activity produces severe turbulence, downdrafts and altimeter errors; lee-side downdrafts can exceed the aircraft's climb capability.

Wind shear on approach is indicated by sudden airspeed and vertical speed changes; a go-around must be initiated if the approach becomes unstable.

Visibility and ceiling minima for IFR approaches are published as DA/DH and RVR or visibility; the crew must not descend below DA/DH unless the required visual reference is in sight.

Spatial disorientation occurs when vestibular and visual cues conflict; in IMC, the pilot must rely on instruments and ignore misleading sensations.

The leans is a somatogravic illusion caused by a sudden linear acceleration or deceleration, producing a false sensation of pitch; it is a common cause of unusual attitudes in IMC.

Hypoxia symptoms appear above 10,000 ft in unacclimatised individuals; supplemental oxygen is required above 10,000 ft for flights exceeding 30 minutes and above 13,000 ft at all times in many States.

Fatigue degrades vigilance, reaction time and decision-making; IFR crews must comply with flight and duty time limitations and use controlled rest where approved.

Crew resource management relies on clear communication, task sharing, monitoring and challenge; the pilot flying and pilot monitoring roles must be defined before departure.

Stress and high workload narrow attention and increase error rates; sterile cockpit rules apply during taxi, take-off, approach and landing.

The human eye adapts slowly to darkness; night vision requires about 30 minutes of dark adaptation and is degraded by bright light and hypoxia.

Carbon monoxide poisoning from cabin heating causes headache, confusion and loss of consciousness; it must be suspected when multiple crew members develop symptoms in flight.

Attitude indicator, heading indicator, altimeter, airspeed indicator, vertical speed indicator, turn coordinator and slip indicator form the core IFR instrument group; the attitude indicator is the primary pitch and bank reference.

Pitot-static system blockage: a blocked pitot tube causes the airspeed indicator to behave like an altimeter; a blocked static source causes airspeed, altitude and vertical speed errors.

The magnetic compass is subject to acceleration and turning errors; it is used to cross-check the heading indicator, not as a primary IFR reference.

Helicopter IFR requires a gyroscopic or electronic attitude reference, a stabilised heading source and, for multi-engine IFR, adequate performance with one engine inoperative.

The standby attitude indicator and standby altimeter/airspeed must be checked before flight and are used if the primary displays fail.

An autopilot or stability augmentation system reduces pilot workload in IMC but must be monitored; an unannunciated disconnect can lead to an unusual attitude.

The helicopter's vibration and rotor-induced vibration can affect instrument readability; instrument panel mounting and anti-vibration provisions are part of the certification basis.

Radio altimeter and low-height warning systems provide height above terrain; they are not a substitute for barometric altitude in IFR procedures.

Standard phraseology includes 'cleared for the approach', 'report established', 'going around' and 'request' phrases; non-standard phraseology increases misunderstanding risk.

A clearance limit is the point to which an aircraft is cleared; if further clearance is not received before reaching the limit, the aircraft must hold at the limit and request further clearance.

Position reports in procedural airspace include aircraft identification, position, time, altitude, next position and ETA, and the following significant point.

Lost communication procedure: continue according to the last acknowledged clearance, squawk 7600, and comply with the published lost-communication procedure for the route.

Emergency squawks: 7700 for general emergency, 7600 for radio failure, 7500 for unlawful interference.

Before descent, the crew must obtain the destination weather, the expected approach and the landing minima; the approach briefing covers the missed approach and the go-around decision.

The pilot monitoring calls out deviations from the desired flight path and speed; the pilot flying makes the go-around decision when the approach is not stabilised.

Read-back of runway-in-use, altimeter setting, SSR code and hold clearance is mandatory; any misunderstanding must be resolved before proceeding.

Translational lift increases with airspeed as the rotor moves out of its own downwash; in IMC, airspeed changes must be managed to avoid settling with power.

Settling with power (vortex ring state) occurs with low airspeed, high rate of descent and high power; recovery requires forward cyclic to gain airspeed and reduce power.

Effective translational lift is normally achieved between 10 and 20 kt; below this, the helicopter is in a high-power, high-vibration regime.

In IMC, the pilot must use attitude and power instruments to control the helicopter; control inputs based on seat-of-the-pants sensations lead to unusual attitudes.

Retreating blade stall occurs at high airspeed and high load factor; it produces vibration and pitch-up and is avoided by observing VNE and load factor limits.

Autorotation in IMC requires prompt lowering of collective and aft cyclic to maintain rotor RPM; the glide is flown at the published autorotation speed.

The helicopter's power required curve shows minimum power at a specific airspeed; IFR cruise planning should account for the increased power required at low airspeed.

Dynamic rollover and ground resonance are ground-handling hazards; in IMC, the transition to hover must be made with reference to instruments and outside visual cues when available.

True airspeed is calculated from indicated airspeed corrected for position error, instrument error, compressibility and density altitude.

Track is the path over the ground; heading is the direction the aircraft points; drift is the angle between heading and track.

Wind triangle: wind component along track (headwind/tailwind) modifies groundspeed; crosswind component produces drift.

RNAV (GNSS) navigation uses waypoints defined by coordinates; the aircraft's flight management system computes track, distance and ETA to each waypoint.

RAIM (receiver autonomous integrity monitoring) detects satellite signal faults; a RAIM prediction is required before RNAV approaches where no SBAS is available.

The flight management system's navigation database must be current; the crew must verify the loaded route and waypoints against the cleared route.

Great circle navigation gives the shortest route between two points; rhumb line navigation maintains a constant track but is longer.

IFR position fixing uses VOR/DME, NDB, GNSS or radar; a fix should be confirmed by at least two independent sources where possible.