Operating Drones Over or Near People

The Civil Aviation Safety Authority (CASA) has several pathways to operate drones Over Or Near People.

For drones above 250g a Remote Operator Certificate is required to obtain an instrument of approval. A Remote Pilot Licence is required for the operating crew.

Each pathway has its advantages and disadvantages and should be carefully considered before the approval process. Choosing a pathway for operating drones Over Or Near People will be dictated by the operation style, environment and drone type.

Available pathways are described in the Temporary Management Instruction for RPA Operations over and near people.

This pathway for operating drones Over or Near People revolves around a controlled ground environment where active participants are briefed on the risk and provide written consent for the drone to operate in proximity to them.

Advantages

• Includes drones up to 25kg

Disadvantages

• Requires written consent
• Requires a controlled ground area

This pathway for operating drones Over or Near People revolves around residual energy on impact that is unlikely to cause harm.

The Civil Aviation Safety Authority has defined two energy figures in Pathway 2.

• Less than 15J, where consent is not required from the people overflown. (Emergency Services can operate up to 34J without consent)
• Less than 34J, where informed consent is required.

There are a number of distinct ways the residual impact energy of the drone can remain below the defined figures.

• Using a parachute system
• Using shelter between the drone and persons
• Using a low-energy drone

Operating drones Over Or Near People using a parachute system is one of the more flexible options. Parachute selection is key for successfully obtaining approval. The parachute system should have

1. ASTM (American Society of Testing and Materials) certification
2. The parachute system must provide a reduction in energy under the desired value
3. The parachute system should stop the propellers on deployment (optional)

The ASTM documentation certifies statements made by the manufacturer, such as minimum deployment height, maximum descent rates and residual impact energy.

Advantages

• Considerably lowers the residual impact energy
• Allows operations over or near people without consent*
• No controlled ground environment is required.

Disadvantages

• Minimum operating height (to allow for parachute deployment)
• Max vehicle speed 50km/hr

*consent required above 15J or a moving vehicle >50 km/hr

Sheltering is one of the quickest ways to operate drones Over Or Near People. Most small drones do not penetrate most modern shelters.

Advantages

• Penetration of shelter is self-declared
• Drone energy calculations are relatively simple

Disadvantages

• Limited to those people in shelter
• Controlled ground environment
• Max vehicle speed 50km/hr

There is limited availability to change a drone’s maximum performance, and the energy limitations imposed by pathway 2 can be difficult to achieve without sheltering or parachutes. That being said, it is not impossible, and reducing the drone’s maximum height and speed can lower its residual energy at impact.

Disadvantages

• Light weight drone required
• Prop guards required within a 1:1 buffer (ie 10 metre horizontally at 10m height)
• Obstacle avoidance is required for operations closer than 5m

The Specific Operational Risk Assessment (SORA) is a risk methodology developed by the Joint Authorities for Rulemaking on Unmanned Systems (JARUS), of which CASA is a contributor.

The framework has standard mitigators for ground risk and is more flexible in the combinations of mitigators that may be used, outside of those defined by pathways 1 and 2.

Developing a safety case using SORA is more time-consuming for operating drones Over Or Near People and should be considered where one of the other pathways is not fit for purpose.

The standard mitigation methods used in SORA are:

• Buffers from people
• People under shelter
• Tethers
• Parachutes
• Emergency Response Plans

A low robustness mitigation in one area can be complemented by a higher robustness mitigation in another area. Mitigating ground risk is the easiest way to operate drones Over Or Near People using SORA.

SORA also has the ability to accept ground risk where appropriate mitigations are not available. Where this is the case, performance requirements are implemented on the aircraft and significant manufacturer support is required.

Advantages

• Consent not required
• More flexible approach to risk

Disadvantages

• Time-consuming