Technology and Operation Exam Questions
Classes, batteries, sensors and emergency behaviour — the technical side of the remote pilot certificate.
- Classes C0 to C4 and their weight limits
- Maximum take-off mass (MTOM) rather than empty weight
- GNSS, compass and calibration
- Return-to-home and failsafe behaviour
- Checklist-based pre-flight checks
The technical section of the exam tests whether you can correctly classify your drone and operate it safely. Central to this is the C0 to C4 classification system set out in Regulation (EU) 2019/945: together with your remote pilot certificate, it determines which subcategory you're allowed to fly in. Almost every weight limit you'll encounter refers to maximum take-off mass, including battery and payload.
Drone classes at a glance
C0 covers up to 250 g, C1 up to 900 g, C2 up to 4 kg, and C3 and C4 up to 25 kg. C0 and C1 may be flown close to people under A1, C2 under A2 with a 30 m distance, and C3 and C4 only under A3 with a 150 m distance from built-up areas. Older drones without a class marking fall under legacy provisions and are classified based on their take-off mass instead.
Handling batteries correctly
LiPo batteries must never be deep-discharged, overcharged, or stored while damaged. A swollen cell should be retired from use immediately. For storage, a charge level of around 50 to 60 percent is ideal. Always charge under supervision and on a non-flammable surface. Exam questions commonly ask what signs indicate a faulty battery.
GNSS, compass and sensors
Position hold relies on GNSS signals, which become unreliable in narrow streets between tall buildings, under tree cover, or near large metal structures. The compass is sensitive to magnetic interference, for example from rebar in concrete or high-voltage power lines. This is why calibration should always be carried out in an open area away from any metal.
Failsafe behaviour and pre-flight checks
If the connection is lost, the drone carries out its configured failsafe action, most commonly return-to-home. The return height must clear every obstacle in the surrounding area, or the drone risks colliding with something on the way back. A proper pre-flight check covers propeller condition, secure battery attachment, firmware, unobstructed sensors, calibration, the home point, and a check of weather and airspace.
Frequently Asked Questions
What does MTOM mean?
Maximum take-off mass — the weight of the drone ready to fly, including battery and payload. All weight-based limits refer to this figure.
What happens if the connection is lost?
The drone executes its configured failsafe action, typically return-to-home at the pre-set return height.
Which class do I need for A2?
A class C2 drone together with the A2 remote pilot certificate, which together allow a minimum distance of 30 m from uninvolved people.
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