John Stack (1906–1972) was an aerospace engineer.

He won the Collier Trophy, in 1947[1] and 1951.

[2] Stack was born in Lowell, Massachusetts, and graduated from Massachusetts Institute of Technology.

He worked at Langley Research Center from 1928 to 1962, and Republic Aircraft Corporation, from 1962 to 1971.

He worked with the Variable Density Tunnel, on compressible airflow.