RESPEC PROJECT

RESPEC provided electrical, mechanical, and fire-protection consulting services for a new regional Search and Rescue (SAR) hangar for the North Slope Borough (NSB) in the extreme arctic climate of Utqiagvik, Alaska. The 35,000-square-foot facility houses the NSB’s two medical evacuation airplanes and two SAR helicopters, along with support services for aircraft maintenance, 24/7 pilot standby, mission planning and support, and day-to-day administrative offices.

At the project outset, the RESPEC team performed a condition survey of the existing, 1980s era hangar. The survey covered code compliance, infrastructure, systems, and the capability to accomplish SAR’s mission in a rapidly changing arctic environment, which included adding a new helicopter.

Our engineers developed and priced multiple concept designs to renovate and expand the existing hangar, as well as several facility configurations on a parcel adjacent to the existing hangar. Based on the team’s analysis, the NSB opted to build a new hangar, which presented the best opportunity for cost savings; improved the facility lifespan through a design meant for arctic conditions; provided greater energy, space, and functional efficiency; reduced disruptions during construction; and increased capacity for future operations.

An early design package was completed for developing the site and installing piling and a thermal-syphon system. RESPEC also completed early design calculations and concept layouts to provide equipment weights, utility requirements, and site development infrastructure to support the Phase 1 design package.

The team began the Phase 2 hangar design with a full-day mechanical, electrical, and fire-protection charrette in Utqiagvik with key stakeholders and users, including NSB project management, SAR administration, maintenance staff, pilots, and local utilities staff. This effort provided the team with a clear direction on the client’s design priorities and the mechanical, electrical, and plumbing (MEP) system design solutions.

MECHANICAL: The mechanical system design focused on providing systems support to the SAR mission while minimizing the long-term operational costs of the facility. An example of meeting this goal was designing a heating system with a simple, durable design and redundancies while incorporating low-maintenance, noncondensing gas boilers and energy-efficient, variable-speed drives for distribution pumps. The hangar heating system used multiple high-bay, gas-fired, radiant tube heaters to provide energy efficiency and minimize stratification. The hangar ventilation system included 100 percent air-to-air heat recovery, gas-fired duct coils to minimize the central heating plant size, and an innovative delivery system above the hangar doors that doubles as an air curtain when the hangar doors are open and greatly reduces heat loss during the frequent movement of aircraft into and out of the hangar. The hangar heating and ventilation strategy is supplemented by two large, destratification ceiling fans. The ventilation for the administrative wing was supplied by a 100 percent air-to-air heat recovery unit coupled with a displacement ventilation distribution system that greatly reduced energy usage and assists in improving employee health. The plumbing system incorporated low-flow fixtures, trench drains, and an oil-water separator for the hangar, as well as a compressed-air system to support the paint booth, shop, and hangar areas.

ELECTRICAL: The electrical design provided lighting, communications, and utility and generator backup power to the new SAR facility.

Lighting: Lighting for this project was 100 LED and ranged from general, office-type lighting and artwork-style lighting to exterior parking lot and aircraft hangar lighting. The user comfort was balanced with the basic functionality of the facility to produce a mixed lighting style and design.
Energy efficiency was a key factor for this project, and several steps were taken to reduce the overall energy load of the facility. One of these steps was installing a building-wide, central, low-voltage, lighting-control system to automatically turn lighting off during periods when spaces were unoccupied. Most of the lighting in the facility is fully dimmable so individual users can control lighting to their personal preferences. The initial lighting-control system was set to turn on lights to 60 percent illumination upon a space being occupied and give the user the ability to increase to 100 percent illumination via a dimmer switch, if desired. Studies have shown that a person will be comfortable with a decreased lighting level most of the time, which saves energy by 40 percent within these spaces. The exterior lighting is automatically controlled on and off via a photocell linked to the dawn/dusk cycle.

Communications: Communications were brought in from an existing campus facility via an overhead, outside-plant, single-mode, fiber-optic line. The fiber-optic line was brought into a main telecommunications room and converted for distribution throughout the facility via Category 6 copper cables. Because of the critical nature of the SAR facility, it was provided with a full electronic access-control system outfitted with security cameras. A radio communications link was also designed for this project as it was vital to the mission of the facility.

Power: Power for the facility comprises a main electrical utility served from the local utility company (Barrow Utilities and Electric Cooperative, Inc.). This facility supports rescue operations throughout the Alaska North Slope and is considered highly critical to the needs of the community. Continuity of electrical power was at the forefront of the design; therefore, the facility was designed with a backup-power supply for the entire facility and a separate uninterruptible power supply (UPS) for the telecommunications systems. The facility is provided with a standby generator in a natural gas reciprocating style rated at 200 kilowatts.

Another design feature used to reduce energy consumption was the parking lot headbolt heater receptacles that vary the output load based on the outside ambient temperature. These heaters have been effective at reducing the overall energy costs in climates like that of Utqiagvik, where long-season temperatures range from –20° to +20° Fahrenheit.

FIRE PROTECTION: The fire-protection design included code-compliance research for the complex requirements of an aircraft hangar and an enclosed painting room for large objects. The hangar suppression system included a complete wet sprinkler system in conjunction with high-expansion foam (HEF) generators and manual hose stations. Cleanup after an HEF discharge was considered, which included selecting chemicals to avoid negative impacts to the utility’s wastewater treatment plant. The rest of the building is provided with a traditional, wet-head sprinkler system with dry heads used at overhangs and those areas within the building that are subjected to freezing conditions, such as the entry vestibules. A 100-horsepower fire pump with jockey pump assist provides 1,750 gallons per minute of water to the building sprinkler and hangar HEF system. The paint booth was specified with a packaged dry-chemical suppression system.

The fire-alarm system provided building-notification strobes and chimes throughout the office areas and separate notification strobes and horns for the HEF system in the hangar. External strobes were designed to Federal Aviation Administration regulations regarding lighting devices facing airfields. Because of the high temperature swings and overhead radiant heating devices, rate-compensated heat detectors were used in the hangar space to prevent false activation signals from traditional detectors.

COMMISSIONING: RESPEC provided the commissioning services on the project, as well as submittal review, site observation, test witnessing, and general support as the project was installed and tested.

PROJECT CHALLENGES: The project balanced the critical infrastructure requirements of a regional SAR facility while minimizing operational costs and meeting a demanding design schedule and limited budget. Phased construction was used to realize the winter construction season for pile installation and summer construction season for vertical construction.