Walter Raymond Smalling, 56, and Eastern Airlines official for 29 years and the company's aircraft services manager at National Airport, died Sunday at his home in Alexandria after a heart attack.

Mr. Smalling was born in Newark, N.J., and educated in public schools there. During World War II, he served in the National Guard and the Army Signal Corps in the China-Burma-India Theater, where he was attached to the Flying Tigers.

He had held several positions with Eastern in the New York area before moving to Alexandria in 1963. He was a member and past president of both the National-Dulles Airport Club and the Eastern Airlines Management Council.

An elder of the Presbyterian Church, Mr. Smalling was a member of the Old Presbyterian Meeting House in Alexandria where he and his wife directed the Family Ministry, a family service organization.

He was active in community affairs, served on local PTA boards and handled Christmas plane rides sponsored by Eastern for disadvantaged children. He was also a member of the Hopkins House board of directors.

Mr. Smalling is survived by his wife, Jeannette, of the home in Alexandria; a son, Walter R. Jr., of Tampa, Fla.; three daughters, Martha and Melissa, both of the home, and Mrs. Roger C. Buchholz, of Alexandria; his mother, Martha M., of East Orange, N.J.; a sister, Helen Garvey, of West Orange, N.J., and two brothers, Edward H., of Hawthorne N.J., and Raymond P., of Point Pleasant, NJ.