United Airlines and the operator of Washington Dulles are looking at ways to improve some of the aging facilities at the hub airport.

The two are evaluating an addition to concourse C that would benefit both arriving and departing travellers in the more 30-year-old facility. The departures level of the wing would accommodate United's new premium Polaris lounge, while the ground floor would be used to improve the flow of arriving international passengers.

"That's part of improving the passenger experience," Metropolitan Washington Airports Authority (MWAA) chief executive Jack Potter tells FlightGlobal on the potential addition at an event to mark the beginning of Primera Air service at Dulles today.

United, which operates about 63% of seats at the airport, confirms that it is planning an addition to concourse C to house the Polaris lounge, declining to comment further.

The Chicago-based carrier has previously said that its Polaris lounge for international premium passengers at Dulles is scheduled to open in 2019, following a series of delays.

Concourse C, which is part of the C/D midfield terminal at Dulles, opened in the mid-1980s as a temporary facility to house United's then new hub at the airport. While it has been expanded and updated since, it shows its age with passengers frequently complaining about the facility.

Various plans have been proposed to replace concourses C/D but none have come to fruition. Today, the only indication of a future replacement is the location of the airport's underground terminal-concourse train station for concourse C that is about 100m (329ft) south of the existing facility.

Scott Kirby, president of United, said on 21 August that there was "nothing in the hopper" to replace the midfield concourses, citing concerns with costs at Dulles.

"One of the important things about making growth at a hub like Dulles successful is cost base," he said. "Having the cost base go up would be really damaging to the growth process."

The cost to board a passenger at the airport, or cost per enplanement (CPE) fell to $17 last year after nearly a decade above $20. It is on track to fall further in 2018.

"Several years ago, the cost per enplanement [at Dulles] was projected to be about $31," says Jerome Davis, chief revenue officer of MWAA, at the event. "Now it's less than $17… and it's sustainable. That means we have an opportunity to add additional airlines in the future."

In addition to Primera Air's service to London Stansted that began on 22 August, Cathay Pacific Airways will begin new service to Hong Kong from Washington Dulles in September, and United plans to begin Tel Aviv flights in May 2019.

United is also evaluating adding two more flight banks – a period of time when a number of arriving and departing flights are bunched together – at Dulles, a move that could increase flight numbers by up to half. Any changes would occur after it rebanks flights at Denver airport, which is scheduled for early 2019, says Kirby.

Such a move would allow the airline to better utilise its facilities at Dulles, as well as drive further cost reductions as passenger numbers rise.

"As we grow enplanements, CPE drops and it's easier to add more service," says Yil Surehan, vice-president of airline business development at MWAA, at the event.

Passenger traffic at Dulles was up 4.5% to nine million during the first five months of 2018, data from the operator shows.

Source: Cirium Dashboard