HM Armed Smack Inverlyon

Action of 15 August 1915
Part of World War I Atlantic U-boat Campaign
Date 15 August 1915 Location Off the coast of Great Yarmouth, England Result British victory
Belligerents
Imperial German Navy	Royal Navy
Commanders and leaders
Karl Gross †	Ernest Martin Jehan
Strength
UB-4, 14 crewmembers	Inverlyon, unknown number of crew
Casualties and losses
14 KIA, UB-4 sunk	none

Inverlyon was a fishing smack of 59 tons burthen that was a part of the fishing fleet at Lowestoft on the Suffolk coast.[1][3] The wooden boat had a flush deck, two masts, and no engine.[3] Inverlyon's sails were fore-and-aft rigged and may have been red ochre in colour, the traditional sail colour for British smacks.[3][4]

In February 1915, Germany began its first submarine offensive of the First World War. During this campaign, enemy vessels in the German-defined war zone (German: Kriegsgebiet), which encompassed all waters around the United Kingdom, were to be sunk,[5] and the British fishing fleet was not exempt.[6] In mid-June, for example, the German submarine UB-2 had sunk six smacks off Lowestoft in a two-day period.[6][7]

One method devised to deal with U-boat attacks was the decoy or Q-ship, designed to lure submarines that were targeting merchant shipping close enough that concealed guns or other weapons could sink them.[3] Inverlyon was selected to become a Q-ship, was outfitted with either a 3-pounder (47 mm) or a 6-pounder (57 mm) gun,[Note 1] and entered the service of the Royal Navy on 2 August 1915.[1][3] Inverlyon's fishing crew and skipper were all temporarily inducted into the Trawler section of the Royal Naval Reserve. Regular Royal Navy Gunner Ernest Martin Jehan and three other gunners from HMS Dryad—a former torpedo boat operating as a minesweeper from Lowestoft—were assigned to Inverlyon, with Jehan in command.[3]

On 14 August, the 59-ton smack Bona Fide was stopped by a U-boat, boarded, and sunk with explosives 35 nautical miles (40 mi; 65 km) east-northeast from Lowestoft.[6] This attack was probably by UB-4, because she was operating in that area on her fourteenth patrol.[8] Regardless of the identity of Bona Fide's attacker, UB-4 did approach a group of smacks in the vicinity the next day. Unknown to UB-4's commander, Oberleutnant zur See Karl Gross,[Note 2] one of the fishing vessels was the disguised Inverlyon.[3][Note 3]

Around 20:20, UB-4 surfaced near Inverlyon, and Gross, on the conning tower of UB-4, began shouting out commands to Inverlyon's crew in German. Jehan, after waiting until UB-4 closed to within 30 yards (27 m) of Inverlyon, ordered the White Ensign raised and gave the command to open fire. A burst of three rounds from the Inverlyon's weapon scored hits on the conning tower, the second shot destroying part of the bridge and sending Gross into the water. UB-4, with no one at the helm, drifted behind Inverlyon, and when clear, Inverlyon's gunner unleashed another six shots into the hull of UB-4 at point-blank range. All the while, small arms fire from Inverlyon's crew peppered the submarine. The U-boat began going down by the bow, becoming nearly vertical before disappearing below the surface. Inverlyon's fishing skipper, a man named Phillips, dived in to attempt the rescue of a crewman from UB-4. Phillips was unable to reach him before the crewman went under and met same fate as Gross and UB-4's twelve other crewmen.[3]

A smack similar to Inverlyon.

As UB-4 went down she fouled Inverlyon's nets—which had been deployed to keep up the appearance of a real fishing boat—essentially anchoring Inverlyon in place. The Q-ship's crew, not having a wireless set on board, sent word of the encounter with another smack. This was followed up by releasing messenger pigeons the following morning, requesting instructions on what to do with UB-4. The thought of salvaging the snagged U-boat was rejected, so the nets were cut, freeing UB-4 to sink to the bottom.[3] UB-4's wreck lies at position 52°43′N 2°18′E.[9] On 19 November 1915 Jehan was awarded the Distinguished Service Cross (DSC) for the sinking of UB-4,[10] and the crewmen of Inverlyon split the submarine bounty paid by the Admiralty.[3][Note 4]

About three weeks after she sank UB-4, Inverlyon had the opportunity to sink another U-boat, but was unsuccessful.[11] The U-boat encountered may have been either UB-2 or UB-16, which both sank fishing vessels in the area on 7 and 8 September.[12] By 1916,[1] Inverlyon had ended her short-lived Q-ship career and returned to being a fishing boat.[11] Jehan, in addition to his DSC, was subsequently specially promoted to lieutenant on 4 January 1916 for his war service;[13] he retired from the Royal Navy on 29 October 1920.[14]

On 1 February 1917, the German submarine U-55 shelled and sank Inverlyon 15 nautical miles (28 km) from Trevose Head at position 50°47′N 5°5′W; there were no reported casualties.[2][15]

• SMS Seeadler, a sail-rigged vessel that served with distinction during World War I.
• USS Irene Forsyte, a sail rigged Q-ship used by the US Navy during World War II
• USCGC Eagle, one of the last sail-rigged vessels to see combat in World War II.
• HMS Prize, a topsail schooner in which Lieutenant William Sanders earned the Victoria Cross for an action with U-93 during World War I