mobile lounges (people movers) at Dulles International Airport have been operating since John F. Kennedy was president, and they continue to be an important intra-airport transportation tool

The original mobile lounges, which date to the airport’s opening in 1962, were constructed by Chrysler Corp. in association with Budd Co. They can carry more than 100 passengers, both seated and standing. Nineteen remain in service, officials say.

Plane Mates, which date back to 1971, can load passengers directly onto aircraft as well as provide intra-terminal transport. Currently, 30 are in service.

https://www.ffxnow.com/2025/09/22/dulles-mobile-lounges-could-last-another-two-decades-airport-officials-say

https://en.wikipedia.org/wiki/Mobile_lounge#/media/File:TransportationWashingtonDullesAirport.jpg