Droning On

Due to rather sinister military use the term ‘drone’ has negative connotations, but recent deployments for disaster relief in Vanuatu and Nepal show benefits from the technology are huge. Aerial photographer, Spidercam technician and drone operator/builder/trainer Axel Knauer zooms in to the use of multirotor drones.

For a long time Droidworx, now Aeronavics of Raglan, has been considered the ‘Rolls-Royce of drones’. Their Skyjib 8 Heavy Lifter still is the tool of choice for many commercial operators and last October it received US Federal Aviation Administration exemption to operate in Hollywood for cinematography productions.

Founded in 2006, the Chinese company DJI has grown to be the largest drone manufacturer worldwide. Most people know their Phantom quadcopters. Although their innovative potential is huge, their customer support is reported to be poor, which lets their products down for commercial use.

The rapid development of drones has taken authorities worldwide by surprise. Because they are air traffic participants, rules have to be amended or created to maintain safety. NZ Civil Aviation Authority is taking a sensible approach. As participants of the aviation system, drone operators have to familiarise themselves with legislation, airspace, operating limits, and Air Traffic Control (ATC) procedures. Note that common acronyms for drones are unmanned aerial vehicle (UAV), unmanned aerial system (UAS), and more recently and officially remotely piloted aircraft system (RPAS).

In recognising the importance of this market, Aviation New Zealand has created an industry association UAVNZ in conjunction with Callaghan Innovation, a Crown Agency of NZ, tasked with fostering innovation. Last month Callaghan launched the C-Prize UAV Challenge – Next generation UAV Technology for the Screen Industry. The categories are noise reduction for sound, position holding in strong wind, and target tracking.

There are now drones available off-the-shelf with self-launching capability, and growing numbers of ‘commercial operators’ use them under the delusion that they are 100% easy and safe to use. However, the risks of crash, injury, fire, airspace incursions and ethics around privacy issues persist, and need to be managed responsibly. Ultimately safe operation comes down to operator experience and business ethics.

Multirotor drones come in many different shapes and sizes. For light loads, like a GoPro camera, the quadcopter design has firmly established itself. Larger designs have six or eight rotors. The advantages are higher lift, better stability, and some redundancy in case of propulsion failure. These larger designs are capable of carrying anything from a DSLR up to a Red Dragon. Multirotor drones are powered with LiPo batteries. Technology advances can now give up to 20min realistic flight time. Heavy systems will typically have an endurance of around 8 to 12 minutes.

Brushless camera gimbals are now the norm. For accurate framing these gimbals can be remotely controlled in dual-operator mode. Generally, recording is done in-camera. 4k is now widely available. Video downlinks are available in SD and HD at a range up to one to two kilometers. Some systems are capable of live-streaming HD content. Drones should have at least GPS position hold, height hold, and a return to home function as a fail-safe measure. Features like Follow Me (or a subject), Point of Interest, Circle of Interest, and Mission Planning for autonomous flight are a bonus and will become increasingly available.

Operators I have talked to share the view that a ‘code of practice’ or ‘operating standards’ should be established. Updated versions of The Blue Book and the Safety Code of Practice are currently in the pipeline and will incorporate standards to provide guidelines for safe and responsible operation of drones. Although public liability cover is not mandatory in NZ, it is highly recommended and generally required by productions. Insurance products specialised for aviation are available. However, products tailored around the typical applications of drones and NZ legislation are still lacking. Recent hull loss insurance quotes received were far more restrictive than NZ legislation requires and hence not commercially viable.

As the majority of the drone systems have unprotected spinning blades, contact avoidance is the highest priority. In a production environment, ultimately safe distances can’t always be maintained. This requires detailed briefing of everyone present and careful risk assessments. LiPo batteries are inherently volatile. Charging and storage should happen away from combustible environments. Sand is the best extinguisher in case of a battery fire. Water will make it worse. Drones are sometimes used in stadiums. Since it is impossible to obtain everybody’s consent to having a ‘flying lawnmower’ operating in the vicinity, I consider this a high-risk operation.

Control transmission is in the 2.4GHz band, the same frequency as cell phone traffic. With this and all the other RF in a packed stadium, the margins for failure are slim.

Designating safe launch and landing areas is important. Assistance may be required in keeping bystanders, kids, animals at a distance.

Note: Airways NZ has launched a free-of-charge site where all flights should be logged and clearances requested: www.airshare.co.nz