DGAC Bolivia Commercial Pilot (PCA) common mistakes
DGAC Bolivia Commercial Pilot (PCA) · Understand the traps and how to avoid them.
Answering air-law items using general ICAO knowledge or the rules of another Latin American state (for example applying a 12-hour duty limit or a foreign VFR weather minimum) instead of the specific Bolivian DGAC RAB value asked for in the stem.
The syllabus covers generic air law, so candidates study Annex 1, 2 and 8 summaries and never drill the Bolivian Regulaciones Aeronáuticas Bolivianas (RAB) numbers that DGAC actually examines; the national rule differs from the ICAO baseline in several places and the item is written to test the national text.
What to do instead
Build a one-page comparison sheet of every numeric value the RAB sets (validity of licences and ratings, medical certificate durations by age, recency for passenger carriage, VFR minima, fuel reserves, duty and rest limits) with the ICAO figure beside it. Before answering any numeric air-law item, ask which document the stem names; if it names the RAB, use the Bolivian value.
Treating mass-and-balance and takeoff/landing performance as separate arithmetic tasks: computing a weight and a CG position without checking both against the envelope, or reading a takeoff distance from a table and forgetting to apply the pressure-altitude, temperature, wind, slope and contamination corrections in the correct order.
Candidates practise each calculation in isolation, so under exam pressure they produce a number that is arithmetically right but operationally wrong; the distractor options are built from the uncorrected or partially corrected value.
What to do instead
Drill a fixed written sequence: (1) sum masses and moments, (2) plot weight and CG and confirm both inside the envelope including zero-fuel and landing cases, (3) enter the performance chart at pressure altitude, (4) apply temperature, (5) apply wind and slope, (6) apply surface or contamination factor. Write the sequence on the scratch sheet before starting and tick each step.
Confusing the four human-performance model stages, or attributing a described accident sequence to the wrong stage, because the candidate matches on the visible outcome (for example 'the pilot did not go around') rather than on the cue that triggered the failure.
The SHELL and error-model vocabulary is memorised as labels without worked examples, so items that describe a real sequence of events cannot be mapped to a stage; candidates also mix perceptual, decisional and skill-based errors.
What to do instead
For each model stage write one Bolivian or generic accident scenario of two or three lines and the stage it represents. In the exam, underline the first cue in the stem (a warning, an ambiguity, an unmet expectation) and use that cue, not the final outcome, to select the stage.
Reading a METAR or TAF and reporting the flight category from the visibility alone, or misinterpreting the order of groups (wind, visibility, present weather, cloud, temperature, QNH) and the meaning of CAVOK, TEMPO and BECMG.
Candidates learn the code groups as a list but never practise decoding against a category threshold, and they confuse prevailing conditions with temporary or becoming conditions that do not apply at the intended time of flight.
What to do instead
Practise decoding ten METARs and five TAFs per session, and for each one state visibility, ceiling and category explicitly. Learn the rule that CAVOK replaces visibility, weather and cloud groups only when visibility is 10 km or more, no cloud below 5000 ft or the highest minimum sector altitude, and no significant weather. For TAFs, note which group applies at the departure or arrival time before answering.
Computing a heading by applying magnetic variation and deviation in the wrong direction, or confusing true track, true heading, magnetic heading and compass heading when the item gives wind and asks for the heading to steer.
The 'variation east, magnetic least' mnemonic is recalled but applied backwards under time pressure, and candidates do not separate the wind-correction triangle from the subsequent variation and deviation corrections.
What to do instead
Always draw the triangle of velocities and label true track and true heading first, then apply variation to get magnetic, then deviation to get compass. Write the conversion chain on the scratch sheet in one direction only and check it by converting the answer back to true track before selecting an option.
Mixing up VFR and IFR radio and clearance phraseology, or answering a communications item with the correct meaning but the wrong standard readback, for example omitting the mandatory readback of a runway-in-use, an altitude or a heading instruction.
Candidates prepare communications by reading phraseology lists rather than by producing readbacks, so recognition is good but recall of what must be read back is weak; Bolivian ATC phraseology items also test the Spanish-influenced conventions used locally.
What to do instead
Practise producing full readbacks aloud for a set of twenty clearance elements and mark which are mandatory readback items (route clearances, altitude, heading, speed, runway, frequency, transponder codes). Study the local AIP phraseology and the difference between VFR and IFR position reporting before the exam.
Answering radio-navigation and instrument-flight items from the pictorial presentation alone, for example deciding an aircraft is left of course from an HSI or CDI picture without first establishing the selected course and the to/from sense.
Candidates learn the instrument as a picture rather than as a geometry problem, so a reversed sensing or an incorrect to/from interpretation produces a confidently wrong answer; the exam deliberately varies the to/from flag.
What to do instead
For every CDI or HSI item, state in writing: selected course, to/from, needle deflection, then the correction. Use the rule that with a to indication the needle is deflected toward the course, with a from indication away from it. Work through at least thirty pictorial items covering all four quadrants.
Describing an emergency procedure in general terms instead of the specific memory items and their order, for example giving the engine-failure actions without the pitch-for-glide and immediate checklist priorities, or omitting the crew-coordination callouts in a CRM item.
Emergency and CRM content is revised by reading checklists rather than by recall, and candidates answer what should eventually be done rather than what is done first; CRM items are answered as personality judgements rather than as observable behaviours.
What to do instead
Write out the memory items of each critical emergency from blank paper until word-perfect, then rehearse them aloud with the standard callouts. For CRM items, look for the option that describes a specific behaviour (a briefing, a challenge, a cross-check, an assertion) rather than a general attitude such as 'be more aware'.
Confusing aircraft-system descriptions: attributing a function to the wrong subsystem (for example describing what the constant-speed unit does as if it were the waste gate, or mixing the roles of the vacuum pump, the alternator and the voltage regulator) or giving a limitation figure that belongs to a different component.
Systems are studied as diagrams with labels and never as cause-and-effect chains, so the exam's 'what happens if' items cannot be answered from a memorised label.
What to do instead
For each system draw a block diagram with inputs, outputs and the failure consequence of each component, and state one limitation figure per component. Test yourself by covering the labels and reconstructing the diagram, then answering 'what fails if this fails' for every block.
Answering principles-of-flight items by intuition rather than by the four forces and the relevant axis, for example saying that induced drag decreases as speed increases without distinguishing induced from parasite drag, or misidentifying which axis a control surface rotates the aircraft about.
The subject is taught qualitatively and candidates rely on everyday flying feel, which is unreliable at the extremes of the flight envelope that the exam targets; the distractors are plausible intuitive statements.
What to do instead
For each question identify the axis, the force balance and the regime (slow or fast, high or low angle of attack) before reading the options. Memorise the drag curve with both components plotted and the point of minimum total drag, and rehearse the primary and secondary effects of each control in turn.