In the early 1970s, the Cincinnati/Northern Kentucky International Airport (CVG) opened three new unit terminals to better serve its high percentage of origin and destination (O&D) traffic. The new facilities were innovative in the way in which the O&D traffic was processed—landside facilities were subdivided into three unit terminals instead of incorporating the more traditional two-level central terminal building; the terminal drives were separated horizontally at grade level instead of vertical separation; bag claim facilities were located in the infield parking areas instead of the lower level of the terminal building; and the infield bag claim areas were connected to the unit terminals by second-level walkways and underground baggage conveyor systems to eliminate any crossings of the horizontal terminal drives. This concept was very innovative at the time, and was pegged by the industry as the “Cincinnati Concept” (Figure).

Unit Terminal Pros and Cons

In 1968, The Kenton County Airport Board (KCAB), owner and operator of the airport, and the airlines discarded a proposed $72 million central terminal concept and opted instead to construct three unit terminals, each unit consisting of ticketing/check-in facilities adjacent to the enplaning terminal drive, and bag claim facilities at grade, but separated horizontally. Advantages offered at the time included:

• Terminal Drives. The need for upper-level (vertically separated) roadways in the terminal area was eliminated by constructing grade level, horizontally separated terminal drives.
• Cost. The unit terminals could be constructed at approximately one-third of the original proposed cost.
• Convenience. There was potential for significant increases in passenger convenience because bag claim facilities were closer to the automobile parking areas.
• Curb front. All four sides of the new bag claim building were available for curb front usage, which had a significant beneficial impact on passenger convenience.

As with some new concepts, however, the grade-level unit terminals presented operational problems as time passed. For example:

• Ticketing. Three ticketing (check-in) locations were required with each unit terminal rather than a single ticketing location associated with the central terminal. Two locations were in the ticketing building—one at ground level to serve the curb front, another on the second level for passengers using the overhead walkways from the parking. The third location was in the baggage claim building adjacent to parking to provide check-in facilities for passengers using the parking facilities.
• Staffing. The grade-level concept required significant increases in staffing to serve the three ticketing locations. Also, it was difficult for the airlines to cross-utilize personnel due to the distance between the baggage claim and ticketing facilities.
• Passenger Processing. The break from the traditional layout of a single terminal building proved to be confusing to some O&D passengers.
• Concession Services/Revenues. The three unit terminals concept divided the airport’s passenger traffic into thirds, creating the need to provide concession facilities and services in triplicate. This arrangement adversely impacted the financials of the concessionaires by increasing capital costs and providing a smaller passenger market at each of the three terminal locations.

In spite of these drawbacks, the grade-level unit terminal concept worked well at CVG—until the airport began to develop as a connecting hub.

Figure 1. 1972 CVG Domestic Terminals.Three unit terminals serve O&D traffic.

Figure 2. 1994 CVG International/Commuter Hubs.The plan for CVG as a connecting hub.

Figure 3. 2011 CVG Terminal Master Plan. Plan allows for long-range buildout.

Why CVG As a Connecting Hub?

In 1984, Delta Air Lines, Inc. started a small connecting hub operation at CVG. This change was based on several factors:

• The creation of connecting hubs offered airlines a means of serving a larger number of passengers more efficiently and more cost effectively. ( I know what you are thinking—"from the airlines’ perspective!”)
• CVG is strategically located in relation to the populated northeast corridor (within an hour’s air travel time of 50 percent of the nation’s population).
• The Cincinnati region supports a strong O&D passenger base, which is a critical element to the success of a connecting hub.
• The cost of operating at CVG includes a relatively low capital cost of terminal construction and an overall focus on cost control by KCAB.
• The head-to-head competition between Eastern Airlines and Delta Air Lines Inc. at Hartsfield-Atlanta International Airport (ATL) placed ATL near capacity, which created unusually high delays and related high operating costs.
• CVG’s Master Plan included independent parallel runways, providing sufficient airside capacity to support a hubbing operation well into the future.

By 1984, the aviation industry had been deregulated for about six years. The fallout among airlines was also underway, creating some winners and some losers. A particular winner was COMAIR, a commuter airline based in Cincinnati. Delta recognized COMAIR’s importance in filling a niche—air travel to cities within 300 miles (500 kilometers) of Cincinnati but with daily loads that supported 30- and 50-seat aircraft, as compared to the larger aircraft in Delta’s fleet, such as the DC-9, B-737 or B-727. COMAIR’s growth matched several goals outlined in Delta’s strategic plan, and eventually Delta purchased 20 percent of COMAIR’s ownership to ensure continued support of the Cincinnati hubbing operation.

Because of the success of the limited hubbing operation, Delta and COMAIR proposed expanding their operations at CVG again in 1988, requiring significant redesign and construction of the terminal facilities. Several things had to happen to accomplish this transformation:

• The concourses or aircraft parking areas had to be redesigned to accommodate the peaking characteristics of a connecting hub, as most of the increase in passengers places a processing burden on the concourse or airside facilities and not the landside facilities of ticketing, bag claim, curb front and parking.
• Planners had to retain the convenience for the local Cincinnati O&D passenger while streamlining the facilities to accommodate connecting passenger traffic.
• Planners also had to plan for the ultimate build-out of the hub, which requires further expansion of the airfield and landside facilities to accommodate the needs of all airlines.

Transitioning to a Hub: The Plan

PB AvPlan was asked to assist CVG in planning and implementing the transition from an O&D airport with three unit terminals to a major U.S. connecting hub with new terminal facilities for Delta and COMAIR. The plan must also retain the remaining two unit terminals for the other airlines that serve primarily O&D traffic, while addressing the long-term build-out needs of the airport.

As a result of our planning efforts, the concepts constructed for Delta’s and COMAIR’s hubbing operations, as shown in Figure 2 on the previous page, include:

• A new landside terminal and two remote parallel concourses connected by an underground people mover, similar in concept to Atlanta-Hartsfield.
• A new Delta terminal building that houses ticketing on the second level, baggage claim at ground level, and a third level designed to ultimately accommodate a people mover station that will connect to remote parking and future off-airport light-rail service.
• Expansion of the two concourses to simultaneously park and service 52 aircraft.
• Vertically separated roadways constructed with the new terminal to provide a separation of arriving and departing automobile traffic and additional linear footage for ticket counters for O&D travelers. This prompted a planning task force to identify the ultimate build-out of the terminal area, including transitioning to vertically-separated terminal drives for the total airport.
• A people-mover tunnel cut 45 feet (14 meters) deep and 75 (23 meters) feet wide to accommodate a utility corridor, baggage conveyors and the people mover, all in three levels. The people mover tunnel section includes areas for three modes of transportation: walking, moving sidewalks and a cable-driven shuttle people mover system by Otis.

The concept designed for COMAIR required an equal amount of innovation:

• Ticketing facilities would be housed in Delta’s new terminal.
• Commuter/regional aircraft parking areas would be in a separate facility, with 53 commuter aircraft parking positions and a new passenger processing sequence that significantly reduced personnel costs.

An in-depth discussion of the new COMAIR facilities is provided in the following article, “A First : Separate
Terminal for Regional Airline” by Ed Cecil.

Why CVG Succeeds as a Hub

Several years and many projects later, people often ask “Why Cincinnati? What was it that propelled CVG to the hubbing forefront?” There are several key components to the answer.

From Delta’s perspective. Foremost, Cincinnati’s location fit into Delta’s air route system and provided a key location for east/west travel. Secondly, the financial conditions were right and the partnering philosophy of KCAB was critical, as any successful hub needs partnership decisions between the airport operator and the airline.

From the airport’s perspective. KCAB was ready to respond immediately to every move proposed by Delta
and COMAIR. This started with KCAB’s planning efforts. Through PB AvPlan, KCAB continually positioned CVG
to respond to changes in the industry while retaining a focus on convenience for the Cincinnati passenger. Most importantly, this continuous planning process provided us with the opportunity to identify the long-range buildout plan for the terminal area while accommodating the expansion plans of Delta and COMAIR (Figure 3).

Secondly, the facilities were privatized, for the most part, with special facility bonds issued by Delta rather than revenue bonds issued by the KCAB. Thus, the corporate revenues of Delta and not the revenues of CVG were used to issue the bonds. This is an important consideration from two perspectives:

• The cost increases resulting from the expansion project impacted Delta primarily, while the benefits of Delta’s increased traffic and landed weights accrue to all airlines.
• If the air transportation industry slows, Delta will most likely continue to use CVG rather than other hubs because Delta and COMAIR have a higher stake in using facilities they own.

Developing a partnership with the airlines, and in particular with Delta and COMAIR, has proven to be very beneficial to CVG in terms of growth, development and increased service. The connecting hub concept adversely impacts, to some extent, the convenience of the Cincinnati O&D passenger. On the other hand, the Cincinnati passenger now has a choice of more than 500 flights a day to more than 85 cities nonstop, including five international locations. I, for one, certainly do not mind adding ten to twelve minutes to my trip to the airport in exchange for the frequency and nonstop service that I now enjoy.