Oman CAA CPL(H) flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

VFR visibility Class C

At and above 3050 m AMSL, flight visibility must be at least 8 km; below 3050 m it is 5 km, with cloud clearance requirements also applying.

CPL(H) validity period

The licence is valid for 12 months; revalidation requires a proficiency check completed within the 3 months preceding expiry or during the validity period.

Right-of-way converging aircraft

When two aircraft converge at the same level, the aircraft on the right has right-of-way; the other must give way and avoid passing overhead or under.

Free power turbine

In a turboshaft engine, the free power turbine is not mechanically connected to the gas generator and drives the main rotor through the main gearbox.

Mast bumping cause

Mast bumping occurs when rotor thrust approaches zero, allowing the hub to contact the mast; avoid low-G pushovers and negative-G manoeuvres.

Hydraulic boost failure

Loss of hydraulic boost increases control forces; most helicopters have redundant servos and a pressure warning requiring reduced speed and landing.

Density altitude formula

Density altitude equals pressure altitude plus 120 ft for each degree Celsius above ISA temperature; higher values reduce hover and climb performance.

Hover ceiling IGE vs OGE

Hover ceiling in ground effect is higher than out of ground effect because ground effect reduces induced velocity and power required near the surface.

Takeoff decision point

For Category A operations, if an engine fails after the TDP the takeoff is continued; before the TDP the takeoff is rejected and landing made.

Maximum range speed

Maximum range occurs near the speed for minimum power required per unit distance; maximum endurance occurs at minimum power speed.

Time of useful consciousness

The period before hypoxia impairs function decreases rapidly above 10,000 ft; symptoms include euphoria, impaired judgement, and cyanosis.

The leans illusion

A vestibular illusion caused by a slow roll below perception threshold; the pilot incorrectly perceives a bank and may lean the wrong way.

Carbon monoxide poisoning

CO causes headache, dizziness, and cherry-red skin; suspect it with exhaust odours or heater use and land immediately for fresh air.

Alcohol bottle-to-throttle rule

A minimum of 8 hours between alcohol and flight is required, with blood alcohol below 0.02%; effects persist after subjective sobriety.

QNH versus QFE

QNH is pressure reduced to sea level for altimeter setting; QFE is pressure at the aerodrome reference point, giving height above the aerodrome.

Carburettor ice range

Carburettor ice can form between about -5 °C and +25 °C with high humidity; apply carburettor heat proactively when conditions favour icing.

Lenticular clouds meaning

Lenticular clouds indicate mountain wave activity on the lee side, associated with severe turbulence and strong downdrafts.

ISA sea level values

ISA sea level temperature is 15 °C, pressure 1013.25 hPa, and lapse rate 1.98 °C per 1000 ft up to the tropopause.

Great circle versus rhumb line

A great circle is the shortest path between two points on a sphere; a rhumb line maintains a constant bearing on a Mercator chart.

One-in-sixty rule

A 1 nm error at 60 nm equals 1° of track error; use this to calculate heading corrections during dead reckoning navigation.

Variation versus deviation

Variation is the angular difference between true and magnetic north and changes with position; deviation is aircraft-specific and listed on the compass card.

Hovering autorotation

Reduce collective to maintain rotor RPM during a hovering autorotation, then cushion touchdown with collective at the last moment.

MAYDAY call content

Transmit MAYDAY three times, then callsign, position, nature of distress, and intentions; repeat until acknowledged.

PAN-PAN meaning

PAN-PAN, transmitted three times, signals urgency for a situation that is not immediate distress but requires priority handling.

Squawk 7600

Squawk 7600 indicates radio failure; follow lost-communication procedures and land as soon as practicable.

VOR radial interpretation

A VOR radial is the magnetic bearing from the station; radial 090 means the aircraft is on the 090° magnetic bearing from the VOR.

ADF relative bearing

The ADF needle points to the station; relative bearing plus heading equals the magnetic bearing to the station.

DME slant range error

DME measures slant range; error increases with altitude and is negligible at low altitude, so indicated distance exceeds ground distance.

Translational lift

As forward speed increases, the rotor leaves its own downwash, reducing induced velocity and improving efficiency; effective lift increases.

Retreating blade stall signs

Retreating blade stall at high speed and weight causes pitch up, vibration, and roll toward the retreating side; reduce speed and collective.

Vortex ring state recovery

In vortex ring state, increase forward speed and reduce collective to regain clean airflow through the rotor; avoid high power descent.

Dissymmetry of lift

The advancing blade produces more lift than the retreating blade; blade flapping and cyclic feathering equalise lift across the rotor disc.

Emergency landing radio call

Transmit MAYDAY with position, altitude, and intentions, select a landing area, and secure the aircraft before touchdown.