About a dozen of the crewmen managed to escape from the sinking submarine and Lieutenant Godfrey Herbert, commanding officer of Baralong, ordered the survivors to be fired on.

Beginning in April 1915, Herbert ordered his subordinates to cease calling him "Sir", and to address him only by the pseudonym "Captain William McBride".

[citation needed] Throughout the summer of 1915, Baralong continued routine patrol duties in the Irish Sea without encountering the enemy.

On 19 August 1915, U-24 sank the White Star Liner SS Arabic with the loss of 44 lives – this included three Americans and resulted in a diplomatic incident between Germany and the United States.

[4] Meanwhile, about 70 nautical miles (130 km; 81 mi) south of Queenstown, U-27, commanded by Kapitänleutnant Bernd Wegener, stopped the British steamer Nicosian with a warning shot in accordance with cruiser rules.

[7][8] U-27 was lying off Nicosian's port quarter and firing into it when Baralong appeared on the scene, flying the ensign of the United States as a false flag.

[4] Before U-27 came round Nicosian's bow, Baralong hauled down the American flag, hoisted the Royal Navy's White Ensign, and unmasked her guns.

There was a mighty hiss of compressed air from her tanks and the U-27 vanished from sight in a vortex of giant rumbling bubbles, leaving a pall of smoke over the spot where she had been.

Herbert claimed in his report to the Admiralty to have been worried that the German survivors might try to scuttle the steamer as an explanation for why he ordered his men to open fire with small arms.

According to Sub-Lieutenant Gordon Charles Steele: "Wegener ran to a cabin on the upper deck – I later found out it was Manning's bathroom.

"[11] Corporal Collins later recalled that, after Wegener's death, Herbert threw a revolver in the dead German captain's face and screamed, "What about the Lusitania, you bastard!

"[11] An alternative allegation by the Admiralty is that the Germans who boarded Nicosian were killed by the freighter's engine room staff; this report apparently came from the officer commanding the muleteers.

The statements said that five survivors from U-27 managed to board Nicosian, while the rest were shot and killed on Herbert's orders while clinging to the merchant vessel's lifeboat falls.

[13] The memorandum demanded that the captain and crew of Baralong be tried for the murder of unarmed German sailors, threatening to "take the serious decision of retribution for an unpunished crime".

[14] Sir Edward Grey replied through the American ambassador that the incident could be grouped together with three "German crimes" that also took place within 48 hours: the Germans' sinking of SS Arabic, their attack on a stranded British submarine on the neutral Danish coast, and their attack on the crew of the steamship Ruel after they had abandoned ship,[15] and suggested that they be placed before a tribunal composed of US Navy officers.

[20] On 24 September 1915, Baralong sank the U-boat U-41, for which its commanding officer at the time, Lieutenant-Commander Andrew Wilmot-Smith was awarded the DSO, the engineer J. M. Dowie the DSC, and two of the crew received a DSM.

[20] U-41 was in the process of sinking SS Urbino with gunfire when Baralong, which had set out from Falmouth the day before, arrived on the scene, flying an American flag.

When U-41 surfaced near Baralong, the latter allegedly opened fire while continuing to fly the American flag,[citation needed] and sank the U-boat.