Drones and Virtual Reality Speed Control Tower Siting at Boulder City Municipal

Airports function amid dynamic change on many fronts, including technology. Coping with such change is essential, but staying ahead of it is ideal.

Boulder City Municipal Airport (BVU) in Nevada is ahead of the change curve with its novel, yet pragmatic and efficient, use of drone technology to help determine the ideal site and height of its proposed air traffic control tower. In fact, the general aviation airport near Las Vegas may be the first to use such a tech-forward alternative approach for one phase of the traditional FAA tower siting process. At the same time, BVU and its project engineering consultant Kimley-Horn have worked closely with FAA personnel on the process.

The airport has never had an air traffic control tower, and much work remains regarding approvals and funding before it can/will. But the project has been actively moving forward for about five years. In a sense, constructing the tower will be a marker of how things are changing for BVU and the region. As Airport Manager Marissa Adou explains, “The addition of the tower will enhance and bring an extra layer of safety to those traveling in and out of our airport.”

Background and Backlog

Several factors acted as catalysts for the still-developing project. Adou explains that increases in air traffic began at BVU almost 20 years ago along with overall growth of the Las Vegas metropolitan area. Annual passenger volume was up to almost 63,250 in 2022, and the airport logged about 46,660 flight operations last year. Heath Hildebrandt, Aviation Practice lead for Kimley-Horn, notes that air traffic at the airport is steadily growing since the COVID-19 pandemic.  

Given the increases in air traffic—plus BVU’s small size and the big costs of building and operating a tower—the airport applied in 2011 and was accepted into the FAA’s Contract Tower program in 2018. Towers in the federal program are staffed with contract controllers, all of whom meet the same qualifications and training requirements as FAA air traffic controllers, but the program pays their salaries. Interestingly, about half of air traffic control towers in the United States operate under the contract program, and BVU hopes to join the ranks soon.

Other forces have also driven BVU’s effort throughout the years. For one, the COVID-19 pandemic increased general aviation traffic at the airport when more travelers began opting out of commercial airline travel in favor of private flights. Considerable amounts of that traffic are associated with major league football and hockey franchises, games and events. The Las Vegas Grand Prix Formula One car race in 2023 and Super Bowl LVIII, held this year at Allegiant Stadium near the Vegas Strip, both caused significant upticks in private and commercial traffic at BVU. And helicopter tours operated by two airfield tenants continue to be popular with tourists who want birds-eye views of the Grand Canyon, Lake Mead, Hoover Dam and other local attractions.

After BVU was accepted into the Contract Tower Program in 2018, airport officials quickly approached Kimley-Horn for insight about what it would take to build a tower. The engineering, planning and design firm has completed a number of airport projects around the United States, including seven in Nevada in recent years and two at BVU in addition to the siting study. Hildebrandt notes that the firm’s work includes several air traffic control tower siting reports, but none have been constructed yet or are to final design.

New Tech, New Tower

Like other consultants, Kimley-Horn regularly uses high-tech visualization tools to show clients what proposed projects could look like. Around 2020, it also started using more cutting-edge technology for roadway projects, specifically drones and virtual reality headsets to provide comprehensive aerial views and 3-D virtual reality modeling. But at that time, it had not yet applied the technology to an airport project.

In early 2020, BVU hired Kimley-Horn to conduct a $60,000 tower siting study, and later the associated $150,000 environmental assessment. Airport Improvement Program grants are funding 93.75% of both projects, with BVU providing the rest through rent revenue and fees.

The standard FAA air traffic control tower siting process, called Airport Facilities Terminal Integration Laboratory, includes the use of cranes on airport grounds to test and assess potential sites, positions and heights for towers. Officials at BVU were eager to forge ahead with the process, but there was one major problem: an 18- to 24-month backlog for FAA tower siting studies. Given that daunting delay, and the possibility that cranes could need to be on the airfield for weeks, BVU and its consultant opted to use drones instead. “We chose to do that because we could get it done more quickly,” Adou explains.

While FAA approval was not required for drone operations, the airport and Kimley-Horn proceeded with due diligence. The consultant obtained a filming permit from the city Parks and Recreation office and completed an Unmanned Aircraft Systems operator’s compliance statement as required by BVU. “We worked directly with the airport manager [Adou] on a flight schedule that had the least impact to the airport and its air traffic,” Hildebrandt recalls. “Based on these conversations, she issued a NOTAM (Notice to Airmen) and was on hand during the drone flights.”

The Process

FAA’s standard Airport Facilities Terminal Integration Laboratory process uses simulators, virtual reality and 3D modeling technologies, goggles and more. They are used, in part, to assess proposed control tower siting, interior design/layout orientation and height, as well as operational and procedural concepts. The imagery and simulations, however, are based on photos taken from cranes positioned at airports. BVU took an alternative approach and used drones to capture initial on-site imagery. In that sense, this was a new experience for officials and technicians.

In September 2021, two FAA Part 107-certified technicians from Kimley-Horn’s Denver office arrived at BVU and flew two drones: a DJI Mavic 2 Pro for panoramas, and a DJI Matrice 210 for photogrammetry to support surveying and mapping. They flew 24 flights that lasted seven hours over the course of two days, and the two drones scanned the entire airport and airfield at various times of day to account for various sun glare angles.

That imagery, refined during 2021 and 2022, gave the project team a great basis for the 3-D model, Hildebrandt notes. The 3D modeled images rendered from the drone photography enabled controllers to see views from many potential positions at BVU and at varying heights, times of day and in different sunlight conditions. They also provided simulated nighttime views and in wide-ranging weather. That capability gave technicians “a lot of power and control to look at things under different conditions to see what would be optimal,” Hildebrandt explains.

The resulting 3-D imagery was then used to build a 3-D model of the entire airport. A mock air traffic control tower cab was created that included 360-degree views of the airfield from the survey sites. The 3-D model included controls for time of day, weather, height, rotation of the cab, and simulated air traffic. Those things, as well as workstations and static control displays similarly found in control tower cabs, were all incorporated to create as realistic an environment as possible for controllers to evaluate each site. The data was fed into a Meta Quest 2 VR headset, through which controllers could virtually walk around the simulated tower cab and view the airfield. The VR headset and 3-D model were extremely valuable during December 2021 siting meetings attended by FAA personnel and air traffic controllers from Harry Reid International Airport in Las Vegas and nearby Henderson Executive Airport.

The study, driven by alternative drone technology, identified a site for the tower 150 feet from another location that officials were considering. Moreover, it indicated an optimal height of 95 feet for the cab, with antennas above the cab topping out at 125 feet.

“The FAA does not recommend tower sites,” explains Hildebrandt. “The agency informs us if the site and heights are viable.”

The siting study for BVU’s contract tower was submitted to the FAA in May 2022 and approved in August 2022.

Hildebrandt estimates that the novel use and short duration of drone flights for the siting study cut costs in half compared to the traditional use of onsite cranes.

Next Steps

With the siting study approved, BVU’s tower project continues to progress. The environmental assessment is currently underway and expected to be finished by the end of this year. Soon after that, the airport plans to move forward with the design process, beginning in late 2024. AJT Engineering from Florida, which provided initial tower and cab design during the siting study, has been retained for the design.

Eventual construction costs are estimated at $14.5 million. 

A 3D airfield model and mock cab helped controllers evaluate potential sites for a tower.

But the control tower is not BVU’s only current improvement project. In February, crews were finishing up a $6.2 million taxiway reconstruction project that began in late November 2023. Kimley-Horn also is working on that project.

After the successful use of drone technology at BVU, the consultant also used it for a similar tower siting study at Pompano Beach Air Park in Florida. FAA approval for that study is still pending. 

Thus, new technology may become a new trend for the siting of air traffic control. Yet, whatever high-tech tools are used, airports and their consultants continue to focus on safety. “They [BVU] really need a good air traffic control system to keep the traveling public safe,” Hildebrandt concludes.