William Neil McCasland is an American astronautical engineer and retired U.S. Air Force major general. A U.S. Air Force Academy graduate, he earned graduate degrees at MIT and built a career in space research, acquisition, special programs, and operations. His assignments included leadership at the National Reconnaissance Office, direction of space acquisition and special programs in the Pentagon, and command of the Air Force Research Laboratory from 2011 to 2013.

McCasland’s Air Force career was unusually broad even before he commanded the service’s principal research laboratory. He worked in space operations, acquisition, special programs, and assignments connected to the National Reconnaissance Office, then oversaw a research enterprise spanning aerospace vehicles, sensors, materials, information systems, and propulsion. After retiring as a two-star general, he remained connected to technical and advisory networks. That depth explains both his value to DeLonge and the intense attention surrounding his disappearance.

McCasland entered UAP history through emails sent by Tom DeLonge to John Podesta in 2016. DeLonge described McCasland as an adviser who had helped assemble a team and possessed knowledge relevant to UFO disclosure. Those messages establish what DeLonge said; they do not show McCasland confirming claims about Roswell or recovered craft. McCasland’s documented AFRL role nevertheless made the association significant.

On 27 February 2026, McCasland disappeared from his Albuquerque-area home. Bernalillo County authorities and the FBI conducted an extensive search and reported no evidence of foul play; his wife rejected speculation tying the disappearance to dated classified knowledge. His aerospace career links him historically to advanced propulsion research and UAP disclosure, but the missing-person investigation remains a distinct and unresolved chapter of his life.