U.S. Navy Railway Guns : A Case Study in Rapid Prototyping and Acquisition
Mk I gun car of the type that served in France
On 6 September 1918, the 14-inch, 50-caliber Mark IV naval rifle of Battery 2, commanded by Lieutenant Junior Grade E. D. Duckett, USN, of the U.S. naval railway gun unit opened fire on a key German railway hub in France at a range of over 20 miles.
The firing marked the combat debut of a weapon that had been conceived, designed, built, and shipped in only a few months. The firing position at Compiègne was the same spot where the Germans would later sign an armistice ending the war on 11 November 1918—and where France would surrender in World War II. The five batteries—one gun each—of the naval railway unit would go on to fire 782 14-inch rounds on 25 occasions at strategic targets far behind German lines before the war ended. In fact, Battery 4 fired her last round timed to impact seconds before the armistice cease-fire was to go into effect at 1100—possibly, the last shot to impact before the war ended.
This French 320 mm railway gun uses sliding recoil. The jacked-down sleepers are visible at full-size.
The German’s got the jump on the Allies in building rail-mobile long-range artillery that could hit targets very accurately far behind Allied lines without risking vulnerable bomber aircraft—or the even more vulnerable Zeppelin airships.
During 1917, German railway guns regularly bombarded the key port of Dunkirk, France, which was critical to supplying British troops on the Western Front, among other targets. At the peak of the German’s spring 1918 offensive, their largest railway gun—often erroneously referred to as “Big Bertha” (a different gun)—lobbed shells into the city of Paris.
British 12-inch howitzers on top-carriage traversing mounts, traversed 90°, Catterick, December 1940
On the Allied side, the U.S. Navy was the first to develop a similar weapon system. Rear Admiral Ralph Earle, chief of the U.S. Navy Bureau of Ordnance and for whom the Naval Weapons Station Earle, New Jersey, is named, led the development of requirements for the railway guns and for the new type of mine used in the North Sea Mine Barrage.
Mk I gun car with pit prepared, ready for firing
Design work on the weapon commenced at the end of December 1917 and concluded in late January 1918. The first weapons were built and ready to ship by April 1918, as the situation in France became increasingly desperate with the rapid advance of the German army that would eventually run out of steam just short of Paris. The commander of the American Expeditionary Force (AEF), Lieutenant General John J. Pershing, wanted the weapons delivered to France as fast as possible.
The primary reason for the delay between when the weapons were ready to ship and when they went into action was uncertainty as to which ports would still be in Allied hands given the rapid German advance. Efforts by the other Allies, and the U.S. Army, to develop similar long-range rail artillery were generally not completed or deployed before the armistice.
Each of the initial five batteries consisted of one 14-inch naval rifle on a special railroad car. As the newest U.S. battleships were being armed with 16-inch guns, there were a number of spare 14-inch guns that were readily available for use. The guns were assembled at a naval gun factory at the Washington Navy Yard and mated with railway carriages at the Baldwin Locomotive Works and Standard Steel Car Company in Pennsylvania.
Illustration of Baldwin Locomotive Works, 1875
In addition to the gun car, each battery included a locomotive, two ammunition cars with 25 rounds each, two construction materiel cars, a crane, fuel, a workshop, berthing, kitchen and medical cars, all under the command of a Navy lieutenant. The five batteries were each independently mobile, but under the overall command of Rear Admiral Charles P. Plunkett, who had his own staff train. The entire unit had about 25 officers and 500 enlisted personnel.
Due to the limited traverse of the gun, a railway siding would have to be quickly constructed that pointed in the direction of the intended target, hence the construction cars.
Mk II mount
In addition, to elevate the gun, a pit had to be dug underneath the rail bed, and the rails removed due to the width of the gun breech. The Mark II components to the gun fixed these issues, but they were not ready before the war ended.
Moreover, the weight of the gun carriage greatly exceeded the rated capacity of French railroads, so the trains were constrained to a speed of only about five miles per hour.
Photograph of US 14-inch railway gun firing, Thierville-sur-Meuse, France, 1918
However, the mobility of the trains was their best defense, but they were subject to German aerial observation and occasional air attack and counter-battery fire. However, only one U.S. Navy crewman was killed as a result of enemy action and a number wounded.
An example of the Navy railway gun is on display at the Washington Navy Yard. This Mark I gun was used for testing in the United States and is not one of the five that deployed to France. Those were later turned over to the U.S. Army, with some serving as coastal artillery between the world wars before eventually being scrapped.
Map showing firing locations and targets in France, 1918
U.S. Navy Railway Guns : A Case Study in Rapid Prototyping and Acquisition Written by US Navy Admiral Sam Cox