Germany Attacks Mainland USA : Black Sunday

On 21 July, U-156 surfaced just off the Cape Cod town of Orleans and opened fire on the tugboat Perth Amboy, which was towing three barges (some accounts say four).
The tug was quickly in sinking condition and U-156 turned her attention to the barges and opened fire. Because of their low silhouettes, a number of shells went long and impacted in a marshy area near Orleans, although some reports say some structures were damaged. The shelling caused startled bathers to flee the water, while at least one townsperson opened fire on the U-boat with a shotgun, which, of course, did nothing.
There were at least some women and children aboard the tug and barges, so a surfboat from Station 40 of the U.S. Life-Saving Service (later part of the U.S. Coast Guard) valiantly rowed out under fire and succeeded in rescuing all 32 people from the tug and barges.

Townspeople were immediately on the phone to the Boston Globe and to the Naval Air Station at Chatham, Massachusetts. The paper provided an event-by-event reporting, which later became an early example of a media frenzy, and an end result of numerous contradictory reports, such that it is difficult to tell what really happened. The incident served to further fuel the wild rumors and outright hysteria that swept the U.S. east coast during this period, such as reports that German submarines were equipped with aircraft, resulting in anti-aircraft defenses being set up in New York City and the gold dome of Massachusetts’ statehouse being painted over so it could not be used as a navigational landmark.

After initially being incredulous that a submarine was that close in to the shore, NAS Chatham quickly launched at least four (and maybe nine—reports vary) Curtis HS-1L flying boats and R-9 seaplanes. (As an aside, over 600 of the HS-1Ls were built and deployed in the space of a little over a year, an example of U.S. industrial might, once mobilized). A small flotilla of U.S. Navy submarine chasers sortied from Provincetown.

The first aircraft caught the submarine by surprise, but a release lever failed to work on the first aircraft, and bombs failed to explode from several others. Some of the aircraft hit close enough to the submarine that, had the bombs worked properly, the submarine would at least have been damaged. In frustration, one pilot claimed to have thrown a wrench at the submarine.
The sub quickly submerged, then changed her mind and came back up, apparently intending to duke it out on the surface using shrapnel rounds against the aircraft. (It should be noted that only one submarine was confirmed sunk by air attack during World War I, although air cover was very effective at disrupting U-boat attacks on convoys and no ships were lost in convoys that had air cover).
As the attempted air attacks went on for some time, as did the equally fruitless submarine air defense, the flotilla of sub chasers turned back, apparently deciding that discretion was the better part of valor since the submarine’s 5.9-inch guns were much more capable than their own 3-inch guns. The result, however, was that the aircraft and the life-saving boat garnered the glory, which was probably appropriate, and the U.S. Navy did not. U-156 was on the surface for over 90 minutes and fired almost 150 rounds.
In fact, the U.S. Navy took a public beating from politicians and public because despite the hugely expensive naval expansion act of 1916, intended to create a Navy equal to that of any of the world, the Navy could not seem to hunt down and deal with one solitary submarine. Navy leaders, however, quickly reached the conclusion that the U-cruiser operations were just a high-visibility attempt to divert Allied assets from the main effort, i.e., to get as many American troops across the Atlantic as fast as possible in order to regain ground lost to the spring German land offensive.
Following the circus off Orleans, U-156 went into the Gulf of Maine and ran amok amongst the U.S. fishing fleet, sinking 21 of them herself, while manning and arming a captured Canadian trawler that sank seven more. In the end, U-156 sank 34 ships for a total 33,500 tons and, like U-151, had operated with effective impunity off the U.S. east coast for a combined three-month period.

For the most part, both U-151 and U-156 had made an effort to rescue survivors, and their very large hauling capacity and lack of effective opposition gave them the luxury of keeping rescued crewmembers on board until they could be off-loaded safely. However, on 25 September, while attempting to return to Germany, U-156 struck a mine in the recently laid North Sea mine barrage (mostly laid by the U.S. Navy) and sank with all 77 hands. The 100,000 or so mines laid in the North Sea barrage in the summer of 1918 accounted for about six German submarines lost, but was a big morale buster in the German navy. (More on the North Sea mine barrage in a future H-gram.)
By the time U-156 departed the western Atlantic, three more U-cruisers had arrived in waters off the U.S. These were the U-140, U-117, and U-155. U-155 was the former merchant submarine Deutschland, which had made two trips to the United States in 1916 before the country entered the war and before it was converted to a heavily armed U-cruiser. U-140 was of a new class designed from the keel up to be armed U-cruisers, the largest submarines in the world. U-117 was a long-range minelaying submarine.

Like the first two U-cruisers, U-140 was having a field day off the U.S. east coast until she attacked the Brazilian passenger liner Uberaba on 10 August. Unlike most ships, Uberaba attempted to flee when the submarine surfaced to fire warning shots and, as a result, came under direct fire from the U-boat in a running battle and took some hits. Among the 250 passengers (including women and children) aboard the ship were 100 U.S. Navy personnel, many of whom pitched in to stoke coal in order to outrun the U-boat.

Nevertheless, Uberaba got off a distress call, which was answered so quickly by the destroyer USS Stringham (DD-83) that U-140 was caught by surprise and barely managed to submerge. Stringham dropped 15 depth charges and damaged the submarine badly enough that U-140 had to abort her mission and return to Germany in September 1918, having sunk only seven ships. Stringham would go on to earn nine battle stars during World War II, mostly as a fast personnel transport (APD-9).

,After reaching the U.S. east coast about 9 August 1918, U-117 did score a noteworthy success with her mines. On 29 September, the battleship USS Minnesota (BB-22) struck one of U-117’s mines off Fenwick Island, Delaware, which resulted in extensive damage that knocked Minnesota out of the rest of the war, but caused no casualties. It could have been worse, had not Vice Admiral Albert W. Grant (commander of Battleship Force 1) not initiated his own program to have ships under his command reinforce their bulkheads (an action that spared Minnesota the damage that had caused the loss of San Diego). Minnesota was the largest U.S. warship significantly damaged during World War I. (The battleship had been under the command of then-Commander William Sims, unusual at the time (or any time), thanks to political influence of Theodore Roosevelt.
Sims was actually relieved of command of Minnesota in 1911 for making public pro-British statements before that was considered socially acceptable in the U.S. Navy.) The Fletcher-class destroyer named after Vice Admiral Grant (DD-649) fought at the Battle of Surigao Strait during the larger Battle of Leyte Gulf in October 1944. While conducting a night torpedo attack against the Japanese battleship force, she got caught in the cross-fire and was hit 22 times; many of the hits were 6-inch shells from U.S. cruisers. Heavily damaged, with 38 killed and 104 wounded, her crew nevertheless saved their ship despite encountering a typhoon.

When World War I ended, three more U-cruisers were en route the western Atlantic, but they turned back and were surrendered to the Allied forces along with the entire German navy. Six U-boats would end up in U.S. hands, one of which (UC-97) was commanded by Lieutenant Charles A Lockwood (future vice admiral in charge of U.S. submarines in the Pacific during World War II) and is now on the bottom of Lake Michigan. (More on that story in a future H-gram.)
(Sources include America’s U-boats: Terror Trophies of WWI by Chris Dubbs , 2014, The Kaiser’s Lost Kreuzer: A History of U-156 and Germany’s Long-Range Submarine Campaign Against North America, 1918 by Paul N. Hodos, 2017, and NHHC Dictionary of American Fighting Ships entries.)