One hundred years ago, during World War I, the only attack on American soil by the Germans took place on Nauset Beach in Orleans when U-boat 156 fired shells that hit the beach.

That attack was soon answered by seaplanes from the Chatham Naval Air Station, which dropped dud bombs on the U-boat.

It was July 21, 1918, a hot and hazy Sunday, when U-boat 156 lurked in the waters just off Orleans. According to one theory, the submarine was searching for the transatlantic cable that ran from Orleans to Brest, France, with the intent of cutting it. When the U-boat could not find the cable, perhaps its commander became spiteful, surfaced from the depths, and began firing at its nearest target. This happened to be an unarmed, 120-foot steel tug, the Perth Amboy,which was towing four barges with 32 people aboard. As about 1,000 beachgoers watched, some of the shells hit the beach. It was then 10:30 a.m.

The United States had entered World War I in April 1917 and six months later construction of the Naval Air Station began on 44 acres of what old maps call Nickerson’s Neck in Chatham Port. The station was built for $7 million and officially commissioned on Jan. 6, 1918, just seven and one half months before the attack on Orleans. It had two large seaplane hangars and one smaller one, a 252-foot long blimp hangar, a mess hall, barracks for 13 officers and 145 enlisted men, a hospital, radar station, munitions building, hydrogen tank, boat sheds, a shop, a pigeon house for homing pigeons and more. When the station opened in October 1917, local people poured in on foot for the festivities.

During the war, the station’s sailors and aviators mingled with Chatham’s residents. In the 1919 novel “Shavings” by Chatham author Joseph C. Lincoln, one young woman says, “What fun! I’m just crazy about uniforms.”

The station’s mission was to make sure coastal shipping in Nantucket Sound could safely reach Cape Ann. Two seaplanes with Lewis gun and 120-pound TNT bombs regularly patrolled the coast while the blimp made more distant sorties. The station’s first fatality occurred on July 13, 1918 when one of the planes crashed, killing its pilot.

Despite all this surveillance activity, the station knew nothing of the attack on Orleans, just five miles distant, until a surfman in Orleans called the Naval Air Station at 10:49 a.m. to advise the officers that an attack was in progress.

It was just as hot and hazy in Chatham as it was in Orleans, and because it was a Sunday, most of the men who were not on duty had meandered up to a ballgame in Provincetown. Others were out searching for a blimp that had failed to return. Those men who were there loaded bombs onto the only two planes that were available—HS-1L seaplanes or “flying boats.” The first seaplane that took off experienced spark plug trouble and returned after two minutes. The second seaplane was successful and shortly arrived in Orleans, spotting the U-boat on the water’s surface. The seaplane dropped the first bomb, which landed within 40 feet of the sub and failed to detonate. A second seaplane arrived, dropping another dud bomb on the sub. The U-boat, meanwhile, was shooting at the seaplanes.

Finally the pilot of the second seaplane, Phillip Eaton, “threw the heaviest thing he had on board—a monkey wrench—at the sub. It landed on the deck of the sub, much to the astonishment of the submarine’s crew,” according to an account of the incident in the archives of the Chatham Historical Society.

At 11:30 a.m. the U-boat dove for the final time and disappeared.

Communications were primitive at that time. The seaplanes did not have radios. To alert the fishing fleet that the U-boat was in the area, they dropped signal buoys with messages ahead of the boat’s paths. The buoys were marked with red pennants and could be spotted and picked up by the boats. Two pigeons also rode on each patrol plane. Light aluminum containers were strapped to their legs. A pilot could send a message via homing pigeon back to the base. This method worked only by daylight, and not in the fog. In October, thanks to a message carried by a pigeon, word got back to the station that a plane had had to make a forced landing at sea 50 miles from Chatham. After drifting for 27 hours, the men were picked up by a boat from Nantucket.

It is important to note, too, how primitive those HS-1L seaplanes were, powered by noisy Liberty engines, just 15 years after the Wright Brothers’ historic first flight.

The attack on Orleans was a turning point for the Naval Air Station. The Navy sent in 10 new HS-2L “flying boats” to add to the HS-1Ls that were already at the base. Powerful Davis guns were added to the seaplanes. These heavy-firepower guns could attack enemy warships from the air.

During the following fall, the war began to wind down in Europe. More dangerous than the war, though, was the deadly Spanish influenza pandemic that killed between 50 and 100 million people worldwide. (About 20 million people were killed in WWI.) At the Naval Air Station one man died in September. This contrasts with the hundreds of soldiers and sailors who became ill at Camp Devens near Boston.

The war ended on Nov. 11, 1918 with the signing of the armistice. In May 1920 the station was deactivated. It closed in 1923, with most of the buildings demolished in 1924. In the 1960s, ground was broken at the old station for the houses of Eastward Point. To this day strips of concrete from the old field can be found throughout the neighborhood, sometimes hidden under lawns.

For further reading on the Naval Air Station, see “Wings Over Cape Cod: The Chatham Naval Air Station 1917-1922” by Joseph D. Buckley (2000); for more information on the Orleans attack read “Attack on Orleans: The World War I Submarine Raid on Cape Cod” (History Press, 2014) by Jake Klim.

Orleans will commemorate the skirmish with a talk by Klim today (July 19) at 7 p.m. at the Orleans Historical Society Meetinghouse Museum. On July 20 at 7 p.m., Paul Hodos, author of “The Kaiser's Lost Kreuzer,” will give at talk at the Meetinghouse, and on July 21, a commemoration ceremony will be held at Nauset Beach at 5 p.m.