Drones and Construction: Maximizing the benefits while minimizing the risk
by Katie Daniel | September 1, 2016 2:48 pm
By Paul Jeffs
The use of remotely controlled unmanned aerial vehicles (UAVs), better known as drones, has increased dramatically over the last few years—mainly due to improvements in flight and camera technology and decreased purchase prices. In the construction industry, drones are being used for everything from site surveying and planning to getting real-time data of project progress to inspections and monitoring. Further, their data can be used to create digital models or site plans.
The rapid growth in the use of drones has not been without some reported horror stories in the media, such as the recent incident when two CF-18 fighter jets were scrambled into the skies after a large drone was sighted flying near commercial planes over Ottawa. The sometimes-bizarre videos posted on YouTube and other websites also confirm the wide and varied use of the technology and the risks often taken to obtain dramatic or unusual videos and photographs.
In view of the controversial publicity, it may seem incredible that drones are still often used illegally for commercial operations. Certainly, there continues to be a lack of knowledge within the general public regarding what constitutes their legal use and what responsibilities the owners have when operating drones.
Legal responsibilities
The Civil Aviation Authority (CAA) department of Transport Canada (TC) requires the use of drones for commercial purposes—defined as “work or research”—be authorized by a specifically issued Special Flight Operations Certificate (SFOC), which must be valid for each flight or series of flights. During use of a drone, the operator is required to carry a valid SFOC for inspection by any appropriate authority when requested. It is a legal requirement that an SFOC be applied for by a proposed operator before a drone is used for anything but recreational use.
The certificate should be valid for a specified use within a specified region of Canada, for a described period. Typically, the SFOC will impose a considerable number of restrictions and considerations, such as:
- the drone not being flown over crowds, built-up areas, or close to airfields;
- flying the drone only during daylight hours, within visual line-of-sight, and certain maximum altitudes and distances from people and property;
- co-ordination with air traffic services; and
- permission from the property owner to take-off and land the drone.
The proposed operator also has to detail within their SFOC application how they intend to deal with security and safety risks during the use of the drone, together with the contingency plans in the event of an emergency. Pilot and operator experiences and expertise must also be detailed.
Transport Canada is currently exploring changes to its regulatory framework, including new flight rules, aircraft marking and registration requirements, knowledge testing, minimum age limits, and pilot permits for certain applications. It is anticipated any new proposed changes will be announced later this year within the Canada Gazette, at which time comments from the Canadian public can be made.
Penalties
If an incident is reported to Transport Canada, one of its civil aviation inspectors will investigate the following criteria:
- whether an SFOC was issued;
- whether or not the operator followed the laws and regulations; and,
- whether or not safety guidelines were observed.
Transport Canada has advised that local police may also become involved if other laws are broken, including the Criminal Code and privacy laws. If an operator flies a drone without an SFOC when one is required, Transport Canada can issue fines up to $5000 for an individual and up to $25,000 for a corporation. If an operator does not follow the SFOC requirements, Transport Canada can issue fines up to $3000 for an individual and up to $15,000 for a corporation.
| DRONE HISTORY AND GROWTH |
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The earliest attempt at flight by a powered unmanned aerial vehicle (UAV) occurred in 1916, with the first scale remotely operated vehicle flight taking place almost 20 years later. Technology improved considerably during World War II with Germany, in particular, producing and using various types of drones mainly for training purposes. The decades after the war witnessed the dramatic and exponential growth in the international development, production, and use of technology for military combat and aerial surveillance purposes. For example, in 2012, it was reported the United States Air Force (USAF) employed almost 7500 drones. Although the commercial drone industry is still young, the technology for non-military UAVs has improved considerably over the last decade, with major advances being developed within North America, Switzerland, France, Sweden, China, and South Korea. According to one recent market research report, the global UAV market is expected to reach almost US$5.6 billion by 2020, at an estimated compounded annual growth rate of more than 32 per cent between 2015 and 2020.* In 2014, the global market for rotary-blade drones was reportedly valued at more than US$600 million, making it the most widely used type of drone for non-military purposes. In a March 2015 article, The Globe and Mail reported Transport Canada issued 1672 permits for commercial drone applications in 2014, up from only 66 in 2010. |
Commercial liability insurance
Transport Canada also requires flights to be covered by a minimum of $100,000 commercial liability insurance. However, the president of a Guelph, Ont.-based insurance company, Jeff Sutherland, recently noted there are limited offerings to insure drones on an incidental basis only, and that any business which generates revenue exclusively from drones is not currently written.
Apparently, there are two types of coverage offered:
- first-party—or coverage on the drone itself for ‘natural perils’ or ‘all risk’ protection; and
- third-party liability for bodily injury or property damage to others up to $1 million.
Currently, business liability insurance policies exclude drone operations. (For more information from Jeff Sutherland, the president of Sutherland Insurance, see the article, “Thinking of using drones in business, what kind of insurance is required?” published in VentureGuelph.Ca. The February/March 2016 edition is available online at issuu.com/ventureguelph/docs/vtr-aande-febmar2016[1]). However, practices are evolving and some insurance companies will amend policies or offer specific ones to provide for the use of drones. Transport Canada requires proof of insurance[2] be available for inspection during each flight operation.
Importance of obtaining a special flight operations certificate
For processing an SFOC application, the notice required by Transport Canada is currently stated as 20 working days. However, the application process can be difficult to negotiate and those wishing to obtain an SFOC are cautioned the entire process can take several weeks, if not months.
Potential drone users wishing to make a number of flight operations over an extended period are also cautioned that they should apply for a ‘standing’ or ‘blanket’ SFOC, which is typically valid for one year. However, this will require more detailed information to assure Transport Canada the operator has a sufficient track record. Application requirements can be obtained from its website.
Drone technology improvements
Although technical features can vary between manufacturer’s specific models, most modern drones are gyro stabilized and use GPS-aided navigation. Recent design improvements to the rotary blades provide the ability to remain in a fixed position for extended periods. The most common drones are fitted with four rotary blades and are known as quadcopters. However, some are fitted with six or eight rotary blades, providing more power for attached payloads and improved stability during windy conditions.
Typically, drones are also fitted with a compass and flashing light-emitting diodes (LEDs) to provide visual verification of their flight mode, as well as a failsafe activation function for ‘returning home’ in the event of an unfavourable change in safe flight conditions. The use of prop guards is optional but recommended, especially for building inspections. Some of the latest improvements in technology have included ‘vision positioning systems’ that use ultrasound and image data to assist in maintaining position, especially in the event of satellite connection loss for GPS-aided navigation.
Some important improvements have been made over the last decade or so with the introduction of rechargeable lithium batteries that can provide extended flying times. However, these can still restrict some lower-priced models to less than 30-minute flights, depending on temperature and wind conditions. In some cases, batteries may need changing about every 15 minutes, especially at low temperatures. Operators will therefore typically invest in a number of batteries and sophisticated chargers to ensure sufficient power is available to keep drones flying for extended periods.
The specified slider does not exist.
Drones for both commercial and recreational use are typically fitted with gimbal-mounted miniature cameras, which can be used to capture high-resolution images and high-definition (HD) video. Those fitted with vision positioning systems can hover in place to capture sharp images—even when GPS signals are unavailable. (The drone illustrated by Figure 1 was used by this author to capture video footage from which the aerial images used in this article were extracted.) The software provided by most manufacturers will typically include a flight limits function, which is enabled by default and includes height and distance limitations, as well as no-fly zones (NFZ) within which flight operation is automatically excluded. Transport Canada requires drone software be updated before each flight operation, particularly to ensure the latest NFZs are active.
Drones suitable for commercial purposes are controlled remotely by a pilot using a proprietary handheld device. Although some models include built-in monitors within the remote control device, Transport Canada does not permit these to be used by the pilot. Images are therefore generally transmitted wirelessly to tablets, iPads, iPhones, or other handheld devices, operated by a second party who should direct the pilot to the visual locations required to be captured (Figure 2).
Construction applications
Drones are being used within the construction industry for site surveying and planning, measuring stockpiles, and to obtain real-time data for project progress, inspection, and monitoring. They have also been used to identify potential hazards or safety issues, in addition to providing major benefits for final and warranty inspections (Figure 3).
Data captured by some drone’s cameras can be subsequently exported to create 3D digital models or site plans. Some can also be programmed with automated flight paths, so consistent reproducible data can be captured. Additionally, infrared (IR) cameras can be fitted to drones, enabling them to capture thermographic images of roofs, solar panels, and electrical equipment, where changes in recorded temperature can indicate either uniformity or the existence of problems (Figure 4).
Concrete and masonry inspections, along with asset monitoring
In the middle of last year, this author began to use drones to assist in his established consulting practice, which includes condition assessments and inspections of concrete and masonry structures. Since that time, more than 35 buildings have been inspected, including three tall freestanding chimneys. Following the inspections, images extracted from video have been used for a variety of purposes. In Figure 4, for example, overhead aerial views have been used to develop site plans for inclusion in condition assessment reports and contract drawings.
Figure 5 illustrates drone inspections carried out on two tall freestanding chimneys. The first was a 27.4-m (90-ft) high abandoned chimney that had never been capped. The inspection—requested because debris had collected at its base—revealed considerable damage to the 19th-century brick masonry at the top of the stack. As a result, emergency repairs were undertaken to stabilize the masonry until full restoration work could be carried out. The masonry mortar joints of the second chimney—a 26.7-m (115-ft) brick stack—were known to have deteriorated, and restoration work was scheduled to take place. The use of a drone was necessary to convey the extent of the work to the bidding contractors. Images extracted from video footage were detailed on contract drawings, and the video, which formed part of the subsequent contract, was provided to the bidders on a USB flash drive so they could accurately assess quantities for their bids.
Some facility managers have begun to use drone inspections in order to thoroughly record the condition of their asset stock so meaningful comparisons can be made in the future. Investigations using mechanical access equipment, where damage is only photographically recorded, can sometimes be confusing when new deterioration is discovered. This is because it can often be difficult to determine whether the damage had been present, but not detected during a previous inspection. However, perhaps the most beneficial use of drones for building and structure investigations is when costly mechanical boom-trucks, swing-stages, or scissor-lifts can be avoided—especially where access is difficult or landscaping could otherwise become damaged (Figure 6).
A natural application for drone technology is the inspection of roofs where damage may not be readily viewable from grade level (Figure 7). Although not a substitute for closeup physical examination, the ease and speed of a drone inspection can be a valuable tool when determining whether or not access to a roof is necessary.
Risk management
Following the safety and security items discussed within this article ensures safe flight operations. However, an experienced, skilled, and competent pilot—who should be aware of all the risks associated with the nature of the flight operations—should always be a prerequisite. The pilot has the sole responsibility to remotely operate and maintain control of the drone within established flying limits, using a single control source provided by the system manufacturer while maintaining continuous unaided visual contact with the drone. The pilot should not operate the camera during flight operations and should always carry out established safe operating checks before each takeoff.
Abiding by a project specific safety plan will also minimize any risk. Prior to conducting a drone inspection, if an update of the drone or remote controller software was installed, extensive operational trial and tests should be carried out to ensure no changes to safe performance were caused by the update. A site survey of buildings, structures, surroundings, or the area to be aerial photographed, should then be carried out to ensure safe conditions exist. Potential hazards such as close-by trees and power and telephone lines should be studied beforehand. The possibility of wireless frequency interference such as nearby communications towers, and the ability to maintain adequate satellite connections especially around high-rise buildings should also be examined.
Operation zones need to be established around each inspected building or structure and, before commencement of operations, boundaries should be identified using traffic cones, caution tape, or other appropriate means. Warning signs should also be temporarily posted to notify individuals encroachment within the operation zones is for authorized personnel only. Entrances to buildings should be temporarily locked or guarded until the drone has cleared the area, and vehicles should not be permitted to park within the operation zone boundaries. A watch-person needs to be appointed to notify persons of the need to keep clear of the boundaries. Where appropriate, and if necessary, sidewalk and street closure permits must be obtained from the appropriate authority.
Perhaps the most important consideration for safe flying is the weather. High winds and gusting conditions provide the greatest challenge to pilots, and rain and snow to the electronic equipment. Low temperature not only considerably reduces battery life, but also adversely influences electronic equipment, including the operation of tablets, notebooks, etc. Flight operations should also only take place when visibility in the area is not less than “three statute miles” (i.e. 4.8 km) and the cloud base is not less than 304.8 m (1000 ft) above ground level.
Emergency contingency plans
A risk assessment should take place for each building/structure inspection or aerial photography operation to consider appropriate measures to take in the event of an accident or emergency. A fire extinguisher and a first aid kit should be on hand during each flight and the location of the nearest hospital, as well as emergency phone numbers and contact names should be kept on file. In the unlikely event of a disaster, 911 emergency services should be immediately contacted and communication with the closest air traffic services (ATS) unit should be established.
Conclusion
There is little doubt the use of drones within the construction industry and other related sectors is here to stay and will continue to grow at an ever-increasing rate. The benefits of their use are considerable, but the risks cannot be ignored. Although modern technology has become sophisticated, there is also little doubt new improvements will be made within the near future—particularly to cameras, battery life, and stability under difficult weather conditions. Of course, the privacy of others should always be respected and appropriate measures should be taken to ensure occupants of buildings are fully aware when drone inspections are in progress.
| COMMERCIAL APPLICATIONS FOR DRONES |
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The number of non-military applications for drone technology is seemingly endless and continues to grow as the technology improves. So far, drones have been used by:
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Paul Jeffs has more than 45 years of experience in the construction industry around the world. He is principal of PJ Materials Consultants Ltd., a Guelph, Ont.-based company that provides consulting and sub-consulting services across Canada for the investigation, construction, and restoration of masonry and concrete structures. He can be reached at pjeffs@pjmc.net[3].
- issuu.com/ventureguelph/docs/vtr-aande-febmar2016: http://issuu.com/ventureguelph/docs/vtr-aande-febmar2016
- Transport Canada requires proof of insurance: http://Visit%20www.tc.gc.ca/eng/civilaviation/drone-safety.html.
- pjeffs@pjmc.net: mailto:pjeffs@pjmc.net
Source URL: https://www.constructioncanada.net/drones-and-construction-maximizing-the-benefits-while-minimizing-the-risk/