CAA NZ CPL Flight Navigation General common mistakes
CAA NZ CPL Flight Navigation General · Understand the traps and how to avoid them.
Treating forecast wind as the actual wind used for the whole flight and never recomputing heading and ground speed after the first in-flight fix, so the navigation log drifts further from reality with each leg.
Candidates practise the planning calculation on the ground and treat the log as a finished product rather than a live document; the exam tests whether they understand that forecast wind is an estimate and that drift accumulates over distance.
What to do instead
Treat the first positive fix as a wind calibration point: derive actual track made good and ground speed, back-calculate the actual wind, then recompute heading and ETA for the remaining legs. Practise this as a written drill so the recomputation becomes routine, and know that the correction grows with time, not distance alone.
Computing fuel from the trip fuel alone and forgetting the fixed reserve, contingency, alternate and final reserve components, or applying the reserve figures to the wrong reference (takeoff vs landing).
The fuel plan is taught as a sum of parts but candidates memorise the arithmetic order rather than the purpose of each component; exam questions deliberately vary which components are given and which must be derived.
What to do instead
Build every fuel answer as an explicit column: taxi, trip, contingency, alternate, final reserve, extra, total. State the rule each component follows (for example final reserve as a time at holding consumption) before doing arithmetic, and check the total against the minimum required fuel for the flight.
Reading a VOR radial or bearing as a track without converting for variation and, where relevant, deviation, then plotting or flying the wrong line.
The chart, the cockpit instrument and the magnetic compass each use a different north reference; candidates conflate them under time pressure and forget the isogonal lines on the chart.
What to do instead
Write the conversion chain on the working paper every time: true to magnetic to compass, and back again. For VOR, remember radials are magnetic and are the bearing from the station, not to it. Do a sanity check by asking which direction the aircraft would actually fly.
Using a GNSS position as the sole means of navigation without checking receiver autonomous integrity monitoring status, database currency, or the required performance (accuracy, integrity, continuity, availability) for the airspace.
GNSS is treated as infallible and always available; candidates do not connect the PBN specification in the airspace description to the equipment and monitoring actions required.
What to do instead
For every GNSS or RNAV question, identify the navigation specification required, the sensors approved for it, and the monitoring actions (RAIM prediction, database validity, alert limits). Learn that loss of integrity requires a stated reversion procedure, not just continuing.
Plotting a position fix from a single radio aid or a single line of position and treating it as a confirmed fix.
Candidates learn the mechanics of a bearing or range but not the geometry of a fix; a single line of position only constrains one axis of the position.
What to do instead
Insist on at least two position lines with a reasonable cut angle, or one line plus a known feature, and record the time of fix. Where only one line is available, treat the position as a line of position and state the uncertainty along it.
Confusing indicated, pressure, density and true altitude, and applying temperature correction in the wrong direction when terrain clearance matters.
The definitions are learned as separate formulas without a physical model; candidates cannot reason about what a cold, low-pressure day does to the altimeter reading.
What to do instead
Anchor the model: the altimeter shows height above the pressure datum set in the subscale, and cold air makes the aircraft lower than indicated. Work one cold-temperature correction example end to end and state the direction of error before calculating.
Mixing units or datums on the navigation log, such as minutes and decimal hours, nautical miles and statute miles, or magnetic and true headings, within a single calculation.
The log has many columns and candidates copy values between them without tracking units; exam distractors are built from exactly these slips.
What to do instead
Annotate every column header with its unit and datum before starting, convert at the point of entry, and do a rough order-of-magnitude check (for example, ground speed times hours must give the distance in the same unit).
Ignoring the effect of mass and balance on takeoff and landing performance and on the navigation fuel burn, treating the mass and balance calculation as a separate exercise from the flight plan.
Syllabus topics are studied in silos; candidates do not connect centre of gravity position and mass to the speeds, distances and fuel flows used elsewhere in the plan.
What to do instead
Link the two: state the planned mass and centre of gravity position, then show how they change the performance figures used in the plan. Practise questions that require a mass and balance result to feed a performance or fuel answer.
Misreading airspace classes, control zones and special use airspace on the chart, particularly the vertical limits and the conditions of entry.
Chart symbology is memorised piecemeal and the vertical extent of airspace is often written as a fraction or small print; candidates answer from the shape on the chart rather than the annotated limits.
What to do instead
For each airspace question, read the vertical limits and the class explicitly, then state the entry requirements (clearance, radio, transponder). Build a one-page table of the classes and their requirements from the current New Zealand publications and revise it until recall is automatic.
Applying a New Zealand domestic rule or publication convention to an international flight, or vice versa, without checking which regime governs the leg.
Candidates learn one set of rules well and assume it transfers; differences in flight plan filing, altimetry, contingency fuel and carriage requirements are exactly what the exam probes.
What to do instead
For every operations question, first identify the regime (domestic, international, or overwater) and the governing publication, then answer. Keep a comparison sheet of the differences in flight plan content, fuel policy and equipment carriage between the two.