Interception of the Rex

The interception of the Italian liner SS Rex was a training exercise and military aviation achievement of the United States Army Air Corps prior to World War II. The tracking and location of an ocean-going vessel by B-17 Flying Fortresses on 12 May 1938 was a major event in the development of a doctrine that led to a United States Air Force independent of the Army. The mission was ostensibly a training exercise for coastal defense of the United States, but was conceived by planners to be a well-publicized demonstration of the capabilities of "heavy bombers (as) long range instruments of power".

The flight was conducted during coastal defense maneuvers held by the Air Corps without the participation of the United States Navy, and apparently without understanding of their purpose by the Army Chief of Staff. Both had continuing disagreements with the leaders of the Air Corps over roles and missions, with the Navy disputing its maritime mission and the Army seeking to limit its role to that of supporting ground forces.

With a characteristic flair for creating publicity, the Air Corps' General Headquarters Air Force (its combat organization) not only successfully made the interception at sea, but exploited both live radio news coverage and dramatic photographs. Although the publicity resulted in a short-term setback for Air Corps ambitions, within a year both U.S. President Franklin D. Roosevelt and future Army Chief of Staff George C. Marshall became new proponents of long-range air power.

Background

Ostfriesland

In July 1921, promoting the concept of an independent Air Force, General Billy Mitchell staged a series of aerial bombing exercises that resulted in the sinking of the former German battleship Ostfriesland by the U.S. Air Service. Incurring the enmity of the Navy, which considered the achievement nothing more than a publicity stunt, Mitchell continued to discredit the battleship as the main weapon for projection of power by sinking several more obsolete ships in the next two years. However, the Air Service was limited by Army policy to being an auxiliary of the ground forces and was unable to obtain a role that would use long distance bombers.

The "Shasta Disaster"

When the Air Service was renamed the Air Corps in 1926, the joint Army-Navy Board was in the process of reconsidering service responsibilities in coastal defense.