A2 CofC Pre-Flight Checks & Battery Safety — Questions and Answers
Question 1: Which of the following is the correct sequence for a drone pre-flight check?
- Check aircraft, battery, propellers, remote controller, then airspace and environment (Correct answer)
- Power on first, then check airspace
- Check airspace only — mechanical checks are optional for open category
- Calibrate compass first, then check battery
Correct answer: Check aircraft, battery, propellers, remote controller, then airspace and environment
A structured pre-flight check should cover the physical aircraft (frame, motors, propellers), battery state, remote controller, and then environmental/airspace factors. This sequence mirrors standard aviation practice and minimises risk of mechanical failure during flight.
Question 2: What is the recommended minimum battery charge level before beginning a drone flight?
- At or above the manufacturer's recommended minimum, typically 100% for planned flights (Correct answer)
- 50% or above for any flight
- 30% is sufficient for short flights
- Battery percentage is irrelevant if the drone shows no warnings
Correct answer: At or above the manufacturer's recommended minimum, typically 100% for planned flights
Best practice is to begin each flight with a fully charged battery (or as close to the manufacturer's recommendation as possible). Battery capacity decreases with age and in cold weather, so starting fully charged provides the maximum safety margin and flight time.
Question 3: What is a LiPo (Lithium Polymer) battery's most important storage requirement when not in use for more than a few days?
- Store at approximately 50–60% charge (storage voltage) in a cool, dry place (Correct answer)
- Store fully charged to preserve cell chemistry
- Store completely discharged to prevent swelling
- Store in the freezer to maintain cell voltage
Correct answer: Store at approximately 50–60% charge (storage voltage) in a cool, dry place
LiPo batteries should be stored at a 'storage voltage' of approximately 3.8 V per cell (around 50–60% charge). Storing fully charged or fully depleted degrades cell chemistry and reduces battery life. Many modern chargers have an automatic storage charge mode.
Question 4: What visual sign indicates a LiPo battery is damaged and should not be used?
- Swelling or puffing of the battery casing (Correct answer)
- A slightly warm casing after use
- Voltage reading 0.1 V below nominal
- A small scratch on the outer wrap
Correct answer: Swelling or puffing of the battery casing
A swollen (puffy) LiPo battery has undergone internal gas formation due to cell damage or degradation. This is a serious fire hazard — swollen batteries must be removed from service immediately, safely discharged, and disposed of at an appropriate facility.
Question 5: Before every flight, a pilot should check the propellers for which of the following?
- Cracks, chips, warping, and secure attachment (Correct answer)
- Only whether they spin freely by hand
- Colour markings to ensure correct orientation only
- Serial numbers match the airframe logbook
Correct answer: Cracks, chips, warping, and secure attachment
Propeller inspection should check for any physical damage (cracks, chips, delamination), warping, and that they are securely and correctly fitted. A damaged or loose propeller can cause loss of control or in-flight failure, making this one of the most critical pre-flight checks.
Question 6: What should a drone pilot do if the aircraft's compass requires calibration before flight?
- Perform the compass calibration away from metal structures, vehicles, and electronic interference as per the manufacturer's procedure (Correct answer)
- Ignore the warning if flying in an open field
- Replace the compass unit immediately
- Fly in manual mode without compass assistance
Correct answer: Perform the compass calibration away from metal structures, vehicles, and electronic interference as per the manufacturer's procedure
Compass calibration must be performed when prompted, following the manufacturer's procedure precisely. Calibrating near metal objects, vehicles, or sources of electromagnetic interference will produce an inaccurate calibration and can lead to erratic flight behaviour or fly-aways.
A2 CofC Pre-Flight Checks & Battery Safety
Which of the following is the correct sequence for a drone pre-flight check?