[Scan-DC] Searching for flight info by aircraft type?

[Andrew Clegg]

Does anyone know of a Web site that offers flight searches by aircraft type? For example, I want to know the next arriving flight to Dulles that will be on a 787. It's easy to find flights coming from a certain city, or flights involving a specific tail number, or flights by a specific airline, but so far I haven't been able to locate a site or app that allows me to search by specific aircraft type.
Andy