GCAA PPL Theory Exam common mistakes
GCAA PPL Theory Exam · Understand the traps and how to avoid them.
Reciting document validity periods, medical certificate durations, and licence privileges from generic ICAO summaries instead of checking the current GCAA rule for each item.
Candidates often revise from abbreviated commercial study notes that blend FAA, EASA and ICAO defaults, so similar-looking periods become interchangeable in memory.
What to do instead
Build a one-page GCAA-specific table with columns for document, validity, privilege and source regulation; update it from the current GCAA publications and test yourself by writing the table from blank before each practice exam.
Leaving the mixture full rich during a high-density-altitude climb because 'full rich is safest', then misreading the resulting rough running as an engine fault.
Car-driving habits and a fear of leaning too far lead candidates to treat rich mixture as universally protective, ignoring the POH leaning schedule and EGT/CHT guidance.
What to do instead
Practise the POH leaning procedure for the specific aircraft: set climb power, lean to the specified EGT or roughness point, then enrich as directed; explain in writing why density altitude changes the required mixture.
Reading takeoff or landing distance from the chart using aerodrome elevation instead of pressure altitude, and applying wind and slope corrections in the wrong order.
Performance charts are multi-panel graphs with small print, and candidates often jump to the first axis they recognise without first converting QNH and temperature to pressure altitude.
What to do instead
Use a fixed worksheet: QNH to pressure altitude, temperature to ISA deviation, then chart entry, then wind, slope, surface and obstacle corrections in the POH order; write the units and intermediate values on every line.
Treating a hyperventilating passenger as hypoxic and giving 100% oxygen while the passenger continues to overbreathe, instead of first slowing the breathing rate.
Hyperventilation and hypoxia share dizziness, tingling, apprehension and visual disturbance, and oxygen is the correct reflex for hypoxia, so the overlap produces a plausible but wrong action.
What to do instead
Memorise a short differentiation script: reassure, coach slow abdominal breathing, reassess; give oxygen only if hypoxia is suspected or symptoms do not settle; practise the script aloud in a simulated cabin scenario.
Interpreting TEMPO in a TAF as the prevailing condition for the whole validity period rather than a temporary fluctuation, and planning fuel and alternates accordingly.
Candidates read a TAF like a plain-language forecast summary and skim over change groups, so the first weather mentioned is remembered as the general expectation.
What to do instead
Decode every TAF group by group on paper: prevailing, BECMG, TEMPO, PROB, FM; state the time window and probability for each group before making a go/no-go or fuel decision.
Plotting the wind vector in the direction the wind is blowing toward rather than from, then applying the wind correction angle on the wrong side of the track.
The 'wind from' convention conflicts with everyday language, and the vector triangle is often memorised as a shape rather than understood as velocities.
What to do instead
Draw the true-north reference first, mark the wind arrow with the 'from' end at the station and the arrowhead pointing downwind, then label heading, track and drift; check the sign of the correction against the wind side before measuring.
Omitting the passenger and crew briefing before a short, familiar flight because the route and aircraft are well known.
Familiarity reduces perceived risk, and checklists are often treated as documents to be completed for the examiner rather than safety barriers for every flight.
What to do instead
Use a standard oral brief covering exits, harnesses, fire, ditching and sterile-cockpit expectations; deliver it aloud before every departure and have the instructor sign a random-flight briefing check.
Stating that an aircraft stalls at a fixed indicated airspeed regardless of weight, bank angle or load factor.
Initial training simplifies the stall to a single number for the clean configuration, and the 1g stall speed is easy to remember without the load-factor relationship.
What to do instead
Derive the relationship: 1g stall speed rises with the square root of load factor and with weight; work numerical examples for 30, 45 and 60 degrees of bank and explain why the stall angle of attack stays constant.
Acknowledging a clearance with 'roger' when it contains a runway, altitude, heading, frequency or route that must be read back.
Casual radio habits and time pressure on a busy frequency encourage short acknowledgements, and candidates underestimate which items are mandatory read-back items.
What to do instead
Memorise a mandatory read-back list and use a fixed sequence: clearance limit, route, altitude, heading, frequency, squawk; read back the full clearance, then ask for confirmation if any item was not copied.
Mixing knots with kilometres per hour, or feet with metres, in crosswind, fuel and navigation calculations without writing units on each line.
GCAA charts and weather products use mixed units, and candidates copy numbers between formulas while trusting the calculator rather than tracking dimensions.
What to do instead
Adopt a unit-first habit: write the unit beside every number, convert to a single working system before calculating, and carry a rough order-of-magnitude check to catch a factor-of-two or factor-of-three error.