Brunei DCA CPL(A) Flight Planning flashcards

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

True airspeed

TAS is the speed of the aircraft through the air mass. It increases with altitude for a given IAS because air density decreases. Approximate TAS ≈ IAS × (1 + 0.02 × altitude in thousands of feet) at low Mach.

Wind correction angle

The angle between heading and track needed to counter wind drift. WCA = arcsin((wind speed / TAS) × sin(wind angle to track)). Positive WCA means wind from the left.

Groundspeed

The speed of the aircraft over the ground. GS = TAS × cos(WCA) + wind component along track. Headwind reduces GS; tailwind increases it. Used to compute ETE and fuel.

Great-circle distance

The shortest distance between two points on the Earth's surface. Measured in nautical miles as 60 × angular distance in degrees. One minute of latitude equals one nautical mile.

Departure formula

Distance in nautical miles between two meridians at a given latitude. Departure = 60 × Δlongitude(deg) × cos(latitude). At the equator departure equals the longitude difference in minutes.

Mach number

Ratio of TAS to the local speed of sound. Mach = TAS / a, where a ≈ 38.9 × √(temperature in Kelvin) knots. Used for high-altitude cruise and speed scheduling.

Trip fuel

Fuel needed from take-off to landing at destination. Computed leg by leg as (distance / groundspeed) × fuel flow. Excludes contingency, alternate, final reserve, and taxi fuel.

Contingency fuel

Fuel to cover unforeseen factors. Typically 5% of planned trip fuel or fuel for 5 minutes holding at 1500 ft, whichever is greater, unless an en-route alternate is nominated.

Final reserve fuel

Fuel to hold for 30 minutes at 1500 ft above the alternate for turbine aircraft, or 45 minutes for piston aircraft. It must remain at landing and is not usable for planning.

Alternate fuel

Fuel from the destination go-around to landing at the alternate, including approach and missed approach. Required when weather at destination may be below minima.

Specific range

Nautical miles flown per unit of fuel. Specific range = TAS / fuel flow. Maximum specific range occurs near the best lift-to-drag speed, giving greatest endurance.

Density altitude

Pressure altitude corrected for temperature. Density altitude = PA + 120 × (OAT − ISA temperature at that PA). Higher density altitude reduces performance and increases take-off distance.

Centre of gravity

The point where the aircraft's mass is considered concentrated. CG = Σ(moment) / Σ(mass), where moment = mass × arm from the datum. Must remain within forward and aft limits.

Regulated take-off mass

The lowest of MTOW, MLW plus trip fuel, and MZFW plus take-off fuel. Ensures landing and structural limits are respected at every stage of the flight.

TODA

Take-off distance available, equal to TORA plus clearway. The length of the take-off run plus clearway declared by the aerodrome. Used to check take-off performance.

V1

Decision speed. The speed by which the pilot must decide to continue or reject the take-off. V1 must not exceed VR. Rejecting above V1 risks runway overrun.

QNH

Altimeter subscale setting that makes the altimeter read altitude above mean sea level when on the ground. Used below the transition altitude.

Pressure altitude

Altitude indicated when the altimeter is set to 1013.25 hPa. Pressure altitude = elevation + 30 × (1013.25 − QNH in hPa). Used for flight levels and performance calculations.

Transition altitude

The altitude at or below which the altimeter is set to QNH. Above the transition level the altimeter is set to standard 1013.25 hPa. The transition layer separates them.

ISA

International Standard Atmosphere: 15 °C and 1013.25 hPa at mean sea level, with a lapse rate of 1.98 °C per 1000 ft up to 36 090 ft. Used as a reference for performance.

Altimeter error high to low

Flying from high pressure to low pressure without resetting the subscale causes the aircraft to be lower than indicated. The error equals 30 ft per hPa of pressure difference.

Semi-circular rule

Cruise level selection by magnetic track. Tracks 000–179° use odd flight levels; tracks 180–359° use even flight levels. Prevents head-on conflicts between aircraft.

Cost index

Ratio of time cost to fuel cost. A higher cost index gives higher cruise speed and greater fuel burn. A lower cost index favours fuel economy.

Step climb

A climb to a higher cruise level as aircraft mass decreases. Optimum altitude rises with decreasing mass, so step climbing reduces fuel burn on long sectors.

ATS flight plan filing time

For IFR flights, file at least 60 minutes before EOBT, or as published by the state. Late filing may delay departure or require re-filing.

ICAO flight plan Item 15

Route item: include SID, airway designators, waypoints, and STAR. Use DCT for direct legs. Must match the cleared route and the operational flight plan.

CHG message

An ATS message that amends a previously filed flight plan. Used to change route, level, or ETA. CNL cancels a flight plan; DEP and ARR are sent by ATS.

AIRAC cycle

A 28-day cycle on which aeronautical information changes become effective at 0901 UTC. Check the AIRAC date on charts and AIP amendments before flight.

NOTAM classes

NOTAMN is a new NOTAM, NOTAMR replaces a previous one, and NOTAMC cancels one. Each contains a Q-code, location, validity period, and lower/upper limits.

MOCA and MEA

MOCA ensures obstacle clearance within a segment; MEA ensures both obstacle clearance and navaid reception. MEAs are higher than MOCAs where reception is limited.

RNAV and RNP

RNAV is area navigation using VOR/DME, GNSS, or DME/DME. RNP adds on-board performance monitoring and alerting. RNAV 5 gives ±5 NM lateral accuracy; RNAV 1/RNP 1 for terminal procedures.

Equal-time point

The point from which it takes the same time to fly to either of two alternates. Distance = (endurance × GS1 × GS2) / (GS1 + GS2). Used for diversion planning.