At Washington Dulles International Airport, reaching the gate can feel like a trip within the trip. Passengers who cannot use the AeroTrain may have to board one of Dulles’s mobile lounges, the airport’s official name for its oversized, bus-like shuttles that carry passengers across the airfield between the main terminal, concourses, and, in some cases, aircraft. The enclosed shuttles represented an ambitious solution when Dulles opened in 1962, but today they add another transfer to an airport experience that already involves long distances.
Dulles currently uses mobile lounges on routes that include the main terminal to Concourse D, which has no AeroTrain station. Similar vehicles called Plane Mates primarily carry international arrivals to Customs. Now, the airport plans to retire the mobile lounges as it expands the AeroTrain and builds new walking routes, according to a joint press release from the Airports Authority, United Airlines, and the U.S. Department of Transportation. The change, part of a more than $20 billion transformation, will unfold in phases over the next decade. Passengers should expect gradual improvements, not an immediate end to the familiar shuttle ride.
Dulles AeroTrain Expansion Will Replace Mobile Lounges
The AeroTrain already connects the main terminal with Concourses A, B, and C. The automated underground trains have operated since 2010, reaching speeds of up to 42 mph and completing trips between stations in less than two minutes. Concourse D remains outside the existing network, leaving some passengers dependent on mobile lounges or a walk through Concourse C. Dulles currently operates 19 mobile lounges and 30 Plane Mates.
New AeroTrain connections will extend rail access as Dulles replaces and modernizes its concourses. Plans also call for a central pedestrian tunnel and more direct walking routes between the terminal, concourses, and gates. Together, those additions will allow the airport to withdraw the mobile lounges from service. The Dulles transformation plan does not provide a specific retirement date, so passengers using the airport during construction may continue encountering the shuttles for several years.
One major improvement is already underway. Concourse E is scheduled to open later in 2026 with 14 new United gates, direct AeroTrain access, and new and upgraded lounges. That opening will expand capacity before the larger concourse replacement and train expansion reach completion. For an upcoming Dulles trip, passengers should continue checking their departure concourse and allow time for the current terminal-to-gate transfer.
New Concourses, Customs, And United Lounges Will Arrive in Phases
Across the airport, the program will create or renovate more than 5 million square feet. The current C/D Concourse, completed in 1985 as an interim facility, will give way to modern concourses with additional gates, more room for larger aircraft, expanded seating, dedicated work areas, restaurants, shops, and passenger amenities. Plans also include improvements to the main terminal, ticketing areas, security screening, parking, and baggage handling while preserving Eero Saarinen’s original terminal design.
International arrivals will eventually gain a walkable route to a new, larger U.S. Customs facility. Most international passengers currently bypass the AeroTrain and travel to Customs through a controlled arrival route, often aboard Plane Mates. The new layout aims to reduce that dependence while creating a more direct connection between international gates and Customs.
Lounge capacity will also grow. United plans additional United Club space and one of the largest United Polaris lounges in its global network, although the airline has not announced its size or opening date. The Metropolitan Washington Airports Authority, United, the U.S. Department of Transportation, and other airport partners will coordinate the phased construction. The Airports Authority and airlines serving Dulles will finance much of the work through municipal bonds, expanding a modernization program that previously carried a $7 billion allocation.
