Drones cut risk on industrial inspections

Paul Boughton

Using drones to avoid sending inspection workers up dangerous heights is one thing, but it would be unadvisable to send drone-mounted inspection cameras over explosive areas like oil and gas installations without proper risk assessment, reports Boris Sedacca.

The use of unmanned, remotely controlled aircraft for site surveys at oil and gas installations is gathering momentum, as well as other sites like wind farms and masts for telecommunication and broadcast.

In the oil and gas sector, tall and complex structures such as oil rigs, platforms and chimney stacks, present a danger for personnel, particularly operations that take place at heights in hostile environments where waves, wind and weather place further demands on the individuals carrying out the tasks.

Cyberhawk is a leading pioneer in the use of drones for industrial inspection, topographical land surveys and aerial photography. Craig Roberts, chief executive officer of Cyberhawk, claims his company has performed over 200 flare inspections to date.

"The drone is not itself intrinsically safe, which means that every time we do an inspection on a offshore flare stack for example, we have to go through a specific risk assessment with the facility," he explains.

"Our drones use battery power which avoids the use of liquid fuel and from an overall health and safety perspective there are more risks from working with liquid fuel. It is subject to having a discussion with hazardous operations personnel to make safety case for each occasion.

Flammable gasses

"In terms of flammable gasses, the item in the vicinity of a flare inspection that is going to be most likely to ignite gasses is the flare itself. This means that for a flare inspection, the risk is extremely low even though the drone is not intrinsically safe.

"If you inspect something where hydrocarbons have not been ignited, for example a cold vent stack, we have to use a gas sensor to be safe, which would trip an alarm if the hydrocarbons go over the explosive limit that has been set for that particular inspection."

Roberts contends that the issue of intrinsic safety can be addressed by going through the appropriate risk mitigation steps. In addition to still imagery, Cyberhawk also use video and thermal photography, so it can perform thermographic surveys too.

The company uses separate cameras at the moment because the way the drones are configured, a gas sensor for ongoing monitoring would be mounted along with something else like a stills camera. A thermal camera would be mounted by itself, but Cyberhawk looking at ways of mounting both types of camera.

As an inspection and surveying company that specialises in the use of drones, an aviation department buys drones in that have been designed for purpose in partnership with the manufacturer. Several modifications are made to the basic drone, so it is not an off-the-shelf product.

The company's market segments are onshore and offshore oil and gas installations in Europe, Middle East and Asia, and power utilities for inspection of electrical power pylons and renewable energy. It has ten to 15 drones in service deployed all around the world except the US, where there is a moratorium on commercial drone flying.

Roberts adds: "The US Federal Aviation Administration (FAA) is going through a number of 'pipe cleaning' activities to see how they will open up its airspace, but right now it is illegal except for academic use, so universities can apply for a particular research permit.

"Some oil and gas companies are using the academic route as a loophole to try and develop technology in anticipation of the skies opening up in 2015. Without this, they have to fall back on traditional access techniques like rope access, scaffolding and 'cherry pickers'.

"This means that you have to shut the refinery down and let it cool off for a flare inspection. With drones, you can inspect the flare in operation so you do not have to shut down production. This saves around $2 million of lost production for a two-day inspection which would otherwise last for seven days."

Cessna-sized drones

Roberts has observed some opening of airspace in Alaska, where ConocoPhillips, BP and Shell are experimenting with the use of large Cessna-sized drones like the Diamond D42 or Boeing ScanEagle. Their longer flight durations also allow them to perform ice flow and environmental monitoring surveys, but they can weigh a few tonnes.

Cyberhawk drones are under 2kg in weight including cameras and equipment, and under one metre in length, we cannot fly beyond visual line-of-sight (VLoS) which is roughly 250 metres. This means that it has to be able to see the drone at all times to comply with the permissions from the UK Civil Aviation Authority (CAA) or other countries' aviation authorities.

In the UK, the company standing flight permission from the CAA which allows certain types of flight with the UK airspace, but before it flies it has to check the airspace map to make sure there are no particular restrictions, for example near a military base, airport or place of environmental concern.

In the rest of Europe, it has worked in Italy, German, Holland and France for example, and again specific flight permission has to be obtained from each country's civil and defence aviation authorities. It cannot currently fly in Belgium because their rules do not permit commercial drone flights currently.

"We will not fly anywhere unless we have official permission," Roberts concludes. "There are also challenges to flying in other countries like South Africa or in the Middle East - for example it will be possible to fly in Saudi Arabia following discussions with the government agencies and aviation authorities."

In June 2013, the European Commission's Remotely Piloted Aircraft Systems (RPAS) Roadmap, paved the way for the safe integration of RPAS into the European airspace starting in 2016. Military exploitation of UAS has grown significantly in the recent years, but this trend has so far not been followed by the civil sector.

Being remotely piloted, RPA can perform tasks that manned systems cannot perform, either for safety or for economic reasons. RPAS are well suited for long duration monitoring tasks or risky flights into ash clouds. They can efficiently complement existing manned aircraft or satellites infrastructure used by governments in crisis management, border control or fire fighting.

RPAS can also deliver profitable commercial aerial services in various areas, such as in precision agriculture and fisheries, power or gas line monitoring, infrastructure inspection, communications and broadcast services, wireless communication relay and satellite augmentation systems, natural resources monitoring, media and entertainment, digital mapping, land and wildlife management, air quality control and management.

Commission gives nod to civil law

The European Commission conducted a broad stakeholders' consultation between 2009 and 2012, which resulted in three major initiatives having been launched. Published in September 2012, "Towards a European strategy for the development of civil applications of Remotely Piloted Aircraft Systems (RPAS)" reports the outcomes of this consultation.

The main conclusions were that RPAS present an important potential for the development of innovative civil applications by creating jobs and achieving useful tasks. To unleash this potential the first priority is to achieve a safe integration of RPAS into the European air system as soon as possible.

This requires the development of appropriate technologies and the implementation of the necessary aviation regulation at EU and national levels. Issues like privacy and data protection or insurance must also be addressed.

It also requires increased coordination between all relevant actors including the European Aviation Safety Agency (EASA), national civil aviation authorities, the European Organisation for Civil Aviation Equipment (EUROCAE), Eurocontrol and the Joint Authorities for Rulemaking on Unmanned Systems (JARUS), and between regulatory and technological developments.

Given the urgency to achieve RPAS safe integration into the civil airspace in view of the potential economic and social benefits of such applications, the UAS Panel called upon the European Commission to take the lead in the development of a Roadmap for safe RPAS integration into European Air System - the RPAS Roadmap.

In October 2013, JARUS published its "Certification Specification for Light Unmanned Rotorcraft Systems." The airworthiness code is applicable to light unmanned rotorcraft systems, conventional helicopters with maximum certified take-off weights not exceeding 750kg. In operational terms, applicability of this airworthiness code is limited to all day and night Visual Line of Sight (VLoS) operations.

Each requirement must be met at each appropriate combination of weight and centre of gravity within the range of loading conditions by tests upon a rotorcraft of the type for which certification is requested, or by calculations based on, and equal in accuracy to, the results of testing; and by systematic investigation of each required combination of weight and centre of gravity.

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