Retired Air Force Maj. Walter G. Fenerty, 42, a civilian attorney in the office of the Air Force judge advocate general, died Saturday at Suburban Hospital after a heart attack.

He had retired from active military duty in 1970 white a judge advocate at Air Force headquaters here. Since then he had been a civilian supervising attorney in the field of legislative drafting and analysis.

Born in Philadephia, Maj. Fenerty was a graduate of the College of the Haly Cross in Wogoester, Mass, and received a degree from Harvard Law School in 1959, when he entered the Mr. Foce.

He saw duty as a judge advocate in Amarillo. Tex., and with the Third Air Force in England before joining Air Force headquarters here.

Maj. Fenerty received several outstanding performance awards for his proposed revisions for a new federal criminal code and his modifications of the laws dealing with national securty problems.

He was a member of the Federal Rap. and Judge Advocates Associations.

He is survived by his wife, Jove M. Fenerty, and a son, David, of the home in Kensington; his parents, Mr. and Mrs. Walter Fenerty, and a sister, Jeanne Marie Fenerty, all of Queens Village. N.Y., two other sister Joan Sharp of Scarsdale, N.Y., and Mary Ellen Rafferty, of Garden City Park, N.Y., and a brother, Paul, of San Francisco.

The family suggests that expressions of sympathy may he in the form of contributions to the the Multiple Selerosis Society.