3DR - Safety

REDLINE Supporting Documents: RPA OPERATIONS SAFETY, 2015, Q1 - Q2

REDLine Aerospace LLC Henderson, NV 89044

DRONE SAFETY from 3DR based on common GPS / control and LOS operations.

Drones can be hazardous if operated incorrectly. Make safety your first priority, and always 

follow these best practices. 

Handling

Spinning propellers can cause serious injury. Become familiar with your drone’s arming 

procedure, and always disarm before handling the propellers. On 3DR RTF and other Pixhawkpowered vehicles, the safety button provides an additional safety measure by blocking power to 

the motors while the button is disabled (blinking red), allowing you to handle the drone safely. 

 

When flying, always make sure to keep a safe distance between yourself and the drone. Don’t 

take off with the drone facing towards you or fly directly over your head. It is your job to ensure 

the safety of the people around you; make sure that spectators maintain a safe distance from your 

drone at all times. 

Visual Line of Sight

Maintaining visual contact with your aircraft is the best assurance of a safe flight. Don’t let the 

drone get too far away from you; keep it where you can easily see its orientation from the ground. 

This is called your visual line of sight and prevents a situation where you cannot recover the 

drone safely. 

Flying within visual line of sight is also a good way to ensure that your radio signals (from the RC 

and telemetry radio systems) aren’t blocked by buildings or other obstructions. If you can’t see 

through it, it’s likely that your radio signal can’t either. 

Under 400 Feet

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3DR - Safety

Keep your drone flying below 400 feet (120 meters) altitude to avoid conflict with full-scale, 

manned aircraft and maintain visual line of sight. To give you an idea of how high that is, the 

Statue of Liberty is 300 feet (93 meters) tall. 

100 Feet from People, Vehicles, and Property

Always maintain at least 100 feet (30 meters) between your drone and people, vehicles, and 

buildings. This rule is important for flying near crowds, buildings, and roads due to potential 

hazards from unplanned landings. 

5 Miles from Airports

To prevent conflict between your drone and manned aircraft, always fly at least five miles (eight 

kilometers) away from all airports and other locations where manned aircraft are in use. Research 

your area to find all areas of restricted airspace near you. 

Failsafes

A failsafe is a pre-programmed behavior designed to prevent a crash in the event of an unsafe 

situation. All ArduCopter vehicles include a GPS failsafe activated by default. 3DR RTF copters 

are also preset with radio control (RC) and low battery failsafe behaviors. 

 

Loss of GPS signal 

 

If the drone looses GPS signal in a flight mode that requires GPS (loiter, 

auto, return-to-launch, guided), it will land automatically, indicated by a 

blinking blue and yellow status LED and a high-high-high-low tone. Always 

fly outside in an open area to improve GPS signal strength. 

 

 

Loss of RC signal 

 

If the drone looses contact with the RC transmitter, it will land automatically, 

indicated by a blinking yellow status LED. If it looses RC signal during a 

mission, it will return to the launch point before landing.

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3DR - Safety

Low battery

 

If the battery reaches 25% charge, the drone will land automatically, 

indicated by a blinking yellow status LED and a quick repeating tone. If the 

battery runs low during a mission, the drone will return to the launch point 

before landing. 

 

Common sense

Your common sense is the best failsafe. Always be ready to regain manual control of the drone in 

the event of an unsafe situation. Before you fly, determine the boundaries of your safe flying area. 

If the drone moves outside the designated area or exhibits instability in flight, switch to stabilize 

mode and land the drone manually. Remember that, despite specific regulations, flying recklessly 

or creating an unsafe situation for the public is always illegal. As the operator, you take 

responsibility for the behavior of your drone at all times.

CITATION: Written by 3DR Safety based on Pixhawk Control currently on use with Mavrik X8 and X4

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