Mozambique INATRO Heavy Vehicle (Pesado) Driving Theory common mistakes
Mozambique INATRO Heavy Vehicle (Pesado) Driving Theory · Understand the traps and how to avoid them.
Treating the 3.5 t gross vehicle weight boundary as applying to the tractor unit alone, and answering questions about whether a category C or C+E licence is required without first establishing the gross combination weight of the vehicle being driven.
Candidates learn the licence categories as a list of letters and memorise 'C = lorry' without internalising that the dividing line between light and heavy vehicle rules, and between C and C+E, depends on gross weights and on whether a trailer is attached. The distinction never becomes operational, so it collapses under exam pressure.
What to do instead
Before answering any licence, tachograph or speed-limit question, write down two figures: the gross vehicle weight of the drawing unit and the gross combination weight with trailer. Practise classifying ten realistic combinations (rigid 12 t, rigid 18 t plus 4 t trailer, tractor unit plus semi-trailer) into the correct licence category and the correct rule set.
Reading a road sign in isolation and answering from the pictogram alone, without checking whether a supplementary panel below it restricts the sign to particular vehicle categories, weights, times or distances.
Sign recognition is drilled as picture-to-meaning pairs, so the candidate's eye stops at the main plate. Supplementary panels are small, text-heavy and often the only place where the heavy-vehicle restriction actually lives, so they are skipped.
What to do instead
Adopt a fixed scanning routine for every sign question: main plate, then sub-plate, then position relative to the junction. Drill specifically on sub-plates that mention weight limits, vehicle classes, length, hazardous goods and time windows, and answer questions where the main plate is permissive but the sub-plate prohibits.
Calculating permissible load by subtracting the tare weight from the gross vehicle weight and stopping there, ignoring the maximum authorised axle mass and the distribution of the load between axles.
Candidates reduce load rules to one subtraction. The axle-load concept is abstract and requires understanding that a legal total can still be illegal on one axle, so it is mentally discarded as a complication rather than treated as a separate limit.
What to do instead
Work numerical problems where the total is legal but one axle is overloaded, and where shifting the load forward or backward fixes it. Always state three numbers in the answer: gross weight, individual axle loads, and the relevant limit for each. Learn that the plated axle ratings, not the gross rating, govern placement.
Answering braking-distance and safe-following-distance questions with the car figures, or with a single stopping distance, rather than scaling for the much greater mass and for the effect of load and road surface.
Most study material and everyday experience is car-based, and the candidate's intuition is calibrated to a small vehicle. The physics of a laden heavy vehicle is counter-intuitive, so the intuitive answer is systematically too short.
What to do instead
Learn the underlying relationship rather than a table: stopping distance grows with speed squared, and a laden heavy vehicle needs substantially more distance than a car at the same speed, more still on wet or downhill gradients. Practise computing following distance as a time gap that increases with speed, load and surface, and rehearse why a light unladen lorry can brake worse than a laden one because of reduced traction.
Treating the tachograph as a device that only records driving time, and answering working-time questions by counting only time behind the wheel while ignoring other work, availability and breaks.
The candidate's mental model is 'the tachograph measures driving', which is true but incomplete. The other activity modes feel like administrative detail, so they are not integrated into rest and working-time calculations.
What to do instead
Build a daily timeline exercise: mark every minute of a 24-hour period into driving, other work, availability and rest, then check the totals against the daily driving limit, the extended driving allowance, the required breaks and the daily and weekly rest rules. Repeat until the four modes are automatic and the arithmetic of a split break is fluent.
Answering alcohol questions with a single legal limit figure and no reference to the lower limit that applies to professional drivers, or to the elimination rate and the morning-after risk.
The candidate memorises one number for the general driver and never learns that professional and novice drivers are held to a stricter threshold. The morning-after scenario is treated as a moral warning rather than a calculable fact.
What to do instead
Learn both thresholds explicitly and attach them to driver categories, then work elimination problems: given a quantity consumed and a time, estimate the residual level at a stated hour and decide whether driving is lawful. Practise stating that only time removes alcohol and that coffee, food and sleep do not change the figure.
Describing the correct action at the scene of an accident in the wrong order, for example moving casualties or removing a motorcyclist's helmet before securing the scene and alerting the emergency services.
The candidate knows each individual action and lists them in whatever order comes to mind. Priority ordering is a separate skill from recall, and it is rarely practised, so a correct set of actions is presented in a dangerous sequence.
What to do instead
Memorise one fixed sequence and rehearse it aloud: protect and signal the scene, alert the emergency services with a precise location and casualty count, then give care within your competence without moving casualties unless there is immediate danger such as fire. Practise helmet and suspected spinal injury scenarios specifically, and state when you must not intervene.
Answering questions about downhill braking and speed control on long descents by describing continuous service-brake use, rather than engine braking with a low gear and correct use of the retarder or exhaust brake.
In a car, the service brake is the natural answer for slowing down, and the candidate transfers that habit. Brake fade from overheating on a heavy vehicle is a physical consequence the candidate has often never experienced, so the risk is not felt.
What to do instead
Learn the mechanism of brake fade: sustained braking converts energy to heat faster than it can dissipate, the drums and pads overheat and friction falls away. Then fix the behaviour: select a low gear before the descent, use the retarder or engine brake as the primary control, apply the service brake in short firm applications rather than riding it, and stop to let the brakes cool if fade begins.
Confusing the meaning of lane markings and traffic-officer or temporary signals with the permanent rules, for example treating a broken centre line as a general permission to overtake regardless of visibility, weight restrictions or an officer's directions.
Markings are learned as a visual vocabulary with one meaning each, detached from the conditions that qualify them. The candidate does not learn the hierarchy in which an officer's signals override signals, which override signs, which override markings.
What to do instead
Learn the hierarchy explicitly and test it with conflict scenarios: officer versus traffic light, temporary roadworks sign versus permanent marking, sign versus marking. Then learn each marking together with its conditions, especially that a broken line permits overtaking only when it is safe and lawful, and that solid lines and hatched areas have specific prohibitions.
Answering fatigue questions by naming rest as the remedy without specifying the preventive rule, such as the maximum continuous driving period before a break and the length of that break, or by relying on caffeine and open windows to continue.
Fatigue is treated as a wellbeing topic rather than a regulated limit, so the candidate offers sensible-sounding advice instead of the specific numeric rule the question is testing. Stimulant countermeasures feel effective in the moment and are repeated as answers.
What to do instead
Learn the break rule as a number: the maximum continuous driving period and the minimum break, plus the daily and weekly totals. Then learn why stimulants fail: they mask fatigue without restoring alertness, and the only effective remedy is sleep. Practise recognising the early warning signs, and rehearse the decision to stop at the first sign rather than at the point of incapacity.