Estimated reading time 19 minutes, 27 seconds.
Most helicopter flight operations in North America fall into one of two categories. First, theres utility work: the kind of flying that takes place low and slow to the ground, often in remote areas and often with a long line attached. Then there are congested-airspace operations, which can require pilots to monitor several radios at once while communicating rapidly and precisely with air traffic control.
And then theres the Sunrise Powerlink project. With 40 helicopters on contract, this 117-mile, 500-kilovolt transmission powerline construction job for San Diego Gas & Electric (SDG&E) in Southern California is one of the largest helicopter-assisted construction projects on record. Since construction operations commenced in late 2010, the project has already logged an astounding 16,000 flight hours, at a pace of 150 to 200 flights a day. The Sunrise Powerlink project isnt just big, however, its also incredibly complex, with an elaborate system of environmentally motivated airspace restrictions that pilots must negotiate at the same time theyre setting towers and stringing wire. In other words, the Sunrise Powerlink job combines the technical challenge of utility work with the intensity of congested airspace operations all in defined flight corridors on a demanding, time-is-money schedule.
In late March, Vertical visited the Sunrise Powerlink project to learn how SDG&E and its contractors have made it work. Innovation has been half the equation: SDG&E and its partners have invented unique ways to conduct flight operations while also meeting their substantial obligations to permitting agencies. The other half has involved continuous communication and co-operation between pilots in the air.
My hats off to the pilots, said SDG&E helicopter manager Mike Manry. The presence of the corridor, the amount of aircraft traffic, the schedule and the mitigation efforts make this a unique job. . . . These guys have really stepped up to do the impossible.
The Sunrise Powerlink project is a massive undertaking in every way, beginning with its price tag, which exceeds $1.8 billion US. It begins at the Imperial Valley substation near El Centro, Calif., and terminates on the outskirts of San Diego, following a zig-zagging path through a patchwork of federal, state and private lands. It has 438 tower sites, in addition to a seven-mile section that runs underground through the town of Alpine, Calif. (west of Alpine, the 500-kilovolt line steps down to 230 kilovolts).
Because the Sunrise Powerlink line will connect San Diego to existing and planned renewable energy sources in southeastern California including solar and wind projects it will help SDG&E fulfill its mandate to supply a third of its power sales from renewable energy sources by 2020. Renewables and reliability, thats the name of the game, said Manry.
Despite the underlying green rationale, however, environmental and community interests have pushed hard against the project; accommodating their concerns in the permitting process took six years and thousands of pages of environmental analysis. And, with more than 50 percent of tower sites inaccessible by road and with new road construction severely limited due to environmental concerns it quickly became clear that helicopters would play a huge role in the construction process.
Typically in powerline construction, helicopter operations are subcontracted through the construction contractor, who provides a turnkey service. On the Sunrise project, the primary contractor is PAR Electrical Contractors Inc., which has in fact subcontracted with a number of utility helicopter operators (such as Winco, Swanson Group Aviation and Mountain Air Helicopters) to move construction workers and materials around the job site, to set some tower components, and to perform specialty flying jobs such as pulling sock line.
In addition to the operators PAR has contracted, SDG&E also took the unusual step of acquiring its own helicopter an Erickson S-64F Aircrane from Erickson Air-Crane to facilitate setting (in sections) the larger 500-kilovolt steel towers, which can be as tall as 182 feet and weigh as much as 120,000 pounds. Although the helicopter, nicknamed Sunbird, is crewed and maintained by Erickson employees, SDG&E decided it made financial sense to buy the machine outright rather than lease it. It turns out it was a smart move, because there has been a fair amount of intermittent downtime on the project, explained Manry. A side benefit of owning the Aircrane is that SDG&E has made the aircraft available to San Diego County for firefighting operations as required.
In addition to having its own helicopter, SDG&E has contracted directly with a number of operators to provide support for the Aircrane, and to move SDG&E personnel and environmental monitors around the project. Thus, SDG&E and PAR are running simultaneous flight operations, and there can be as many as 20 different helicopters in the air at any given time.
Not surprisingly, keeping everyone on the same page has been one of the projects biggest challenges. This has been especially difficult within the limited geographical confines of the project (somewhat controversially, SDG&E chose to designate corridors for flight operations, which provide useful predictability for those operations but also concentrates traffic and noise). Brad Warren, one of Ericksons two lead pilots on the Sunrise Powerlink project, summarized the situation: The sheer number of helicopters here is amazing. . . . you have a wide diversity of folks operating. With so many aircraft operating here, you have to have order and control.
Establishing Order and Control
SDG&E and PAR have approached the task of order and control in a few different ways.
First, SDG&E created an oversight structure in the form of an operations center at its project headquarters in Alpine. This operations center which resembles the operational control centers that are increasingly common in air-medical and oil-and-gas operations has a full-time staff dedicated to tracking helicopters and personnel. Using flight-following systems such as TracPlus, operations center personnel can view the location of all helicopters on the project in near-real-time. Also, SDG&E pilots and ground personnel are required to check in with Sunrise base every time they change their location on the project, so the operations center always has tabs on who is where.
PAR, meanwhile, has a dedicated employee stationed at Sunrise base to track PAR helicopters specifically. And in the field, PAR has hired flight coordinators and air traffic advisors and stationed them at the busiest construction yards to help manage helicopter traffic. These personnel, most of whom have aviation experience, serve as general-purpose dispatchers and help coordinate the hundreds of takeoffs and landings that take place across the project every day.
Yet, while flight coordinators and air traffic advisors can help alert pilots to other traffic in the area, collision avoidance remains fundamentally the responsibility of the pilots. The thing thats gotten us through it is just the amount of communication between the pilots, said Cody Woolstenhulme, a flight coordinator who was working as a helicopter flight instructor before signing on with PAR. The pilots have really done an awesome job of it.
To keep pilots informed and in touch, both SDG&E and PAR conduct daily briefings. Were pretty diligent about them, stressed SDG&E flight operations supervisor Christopher Steeb. For SDG&E pilots, briefings take the form of an evening conference call, while PAR pilots are briefed at morning tailboards.
These briefings are opportunities for pilots to learn about modifications to policies and procedures. Theyre also opportunities for pilots to raise their concerns which are probably inevitable on a project of this size and complexity. Explained Manry, You need to create avenues for people to tell you how its going.
The Environmental Angle
If congested airspace were the only thing that Sunrise pilots had to worry about, the job would be challenging, but not too different from other large, busy construction projects. What really makes the project unique is the degree to which it has been shaped by environmental restrictions not only on the ground, but also in the air. Golden eagles, bighorn sheep and other endangered and threatened species have critical habitat along the Sunrise Powerlink route, and permitting agencies for the project made project approval contingent upon a number of environmental mitigation efforts, some of which are extremely limiting.
For example, during golden eagle nesting season, work must cease on sections of the powerline that run near eagle nests; this has resulted in the line being built in a piecemeal fashion. Yet, even if theyre not actively working in the area, helicopters on the project are prohibited from flying within 4,200 feet of active and historic golden eagle nests. SDG&E actually went beyond the required mitigation measures and created additional buffer zones around bird nesting areas; some of these require pre-authorization to enter and work in. Even the buffer areas of 100 to 500 feet that exist for other bird species nests can be very restrictive when the nests exist in high concentrations. During the last golden eagle nesting season (which runs from mid-December through July), biologists identified around 1,000 nests of concern; they expected to find about twice that number this year.
Since, thats clearly far too many to keep track of on a sectional chart, what were operators to do? One approach might have been to simply ignore the restrictions, but in Southern California, that wasnt an option. Said Manry, The agencies expect 100 percent compliance perfection is our standard.
Forced to develop a workable system for complying with environmental mandates, SDG&E turned to technology. It purchased Garmin 696 (and, more recently, 796) GPS devices for every helicopter on the project, and developed a system for programming the devices with all the requisite aerial restrictions. Now, every morning, pilots receive a GPS push containing all the current restricted areas. These appear as circles on the GPS moving maps, allowing pilots to see and navigate around them in flight.
With the GPS providing guidance, and the flight following technology recording every flight path, SDG&E can prove to skeptical homeowners and environmental monitors that the helicopters are where theyre supposed to be. While the same flight-following technology can also be used to confirm violations, Manry said that on balance the system has worked in the operators favor: The technology has helped us. It has allowed us to go back and breadcrumb where the helicopter flew [at the time of a complaint]. The system has been a good tool for us to get back to the customers on the ground.
Of course, while the GPS system did much to solve the compliance problem, it also introduced an additional layer of complexity into the cockpit. Erickson co-lead pilot Warren likened the system to instrument flight rules operations: Its all about pre-planning. Guys have to be on their toes. This is not an analogy that is often used in utility work, which is generally about as visual as flight operations get.
Indeed, some pilots have refused to fly on the project out of concern that the congested airspace and environmental restrictions have created an unsafe working environment. Others have simply been unable to meet the level of technical skill and multi-tasking ability required by the job, and have left of their own accord, or been released for reasons related to general performance or specific violations. Noted PAR flight coordinator Woolstenhulme, You see a lot of pilots come and go quick, because they just dont have the skills to be here. This is a technical job. Its demanding for sure.
As innovative as SDG&Es GPS system may be, few pilots on the Sunrise Powerlink project are enthusiastic about negotiating the complex maze of environmental restrictions. Other innovations on the project, however, have been embraced by virtually everyone.
From a construction perspective, one of the projects innovations has been the development of specialty steel caps for the micropile foundations that anchor the towers at remote sites. Traditional anchoring methods use as much as 130,000 pounds of concrete per tower, but the micropile system uses far less, reducing helicopter flights to remote sites by as many as 50 per structure.
From an aviation perspective, probably the most notable innovation has been a pioneering brace system that dramatically simplifies the process of erecting split bridges the pieces that form the tops of the largest towers. Because the steel transmission towers are so massive, theyre erected in pieces by the Aircrane, which sets the towers base first, followed by its body, its laybacks, and, finally, the bridge that spans the laybacks and holds the conductors. On the smaller towers, the Aircrane is able to set the bridge in one piece. On the largest towers, however, the bridge is split into two halves, each of which attaches to one of the two supporting laybacks.
Initially, erecting the split bridges was a difficult and time-consuming process. The Aircrane would hover in place with the split bridge for as long as 20 minutes while line workers toiled underneath the helicopter to secure the split bridge to the tower. SDG&E decided the practice was too risky, however, so it sought a better way.
A group was commissioned to design a system that would allow the Aircrane to set the split bridges without assistance from crews on the tower. The resulting two-part brace system the group developed bolts onto the bridges and laybacks; the braces lock together to hold the pieces in place temporarily, then line workers complete the attachment process once the helicopter is out of the way. Its the coolest thing to come out of the project, said the other of Ericksons two lead pilots, Bill Neckels. It transformed the pick from one that took 30 minutes and 15 guys, to one that takes three minutes and zero guys. The brace system is one of the many lasting legacies that are likely to come out of the Sunrise Powerlink project.
For the project itself, by late March construction work was around 80 percent complete, and SDG&E hoped to have the line finished and energized later this year. With everything the utility has learned from it, Manry forecasted more projects like it in the future (SDG&E is even exploring the possibility of creating a permanent, dedicated helicopter department). Sunrise has brought to light the fact that the helicopter will play a bigger role in [powerline] construction and maintenance, said Manry. He predicted that environmental concerns would continue to drive a need for helicopters as an alternative to environmentally damaging road construction, as well as dictate the way helicopters operate.
With its size and complexity, the Sunrise Powerlink project is likely to generate a number of lessons learned that will influence future operations. The jury is still out on some of those lessons, but in the meantime the projects 16,000 flight hours are a tremendous testament to what the helicopter industry can accomplish under pressure.
Its been a unique project, reflected Erickson co-lead pilot Warren. Its a complex project, with all of the agencies involved. Weve got a lot of folks weve got to make happy. Thats the way it is in the world today.