[1] For surface running, the boats were powered by two 500-brake-horsepower (373 kW) diesel engines, each driving one propeller shaft.

[4] On 6 December 1943, Ro-111 departed Penang to begin her first war patrol, tasked with raiding Allied shipping in the Bay of Bengal.

[4] The Royal Australian Navy corvette HMAS Ipswich rescued all 134 men on board Peshawur, including her entire crew of 125 and all nine of her embarked gunners.

[4] At 09:00 on 7 March 1944, Ro-111 put to sea from Penang to begin her fourth war patrol, briefly escorted by the torpedo boats T-451 and T-455 as she departed.

[4] While the rest of the convoy and all of its escorts left the area, the Norwegian steamer Lovstad stopped her engines and rescued El Madina′s 814 survivors.

[4] On 28 March 1944 she departed Penang and set course for Sasebo, Japan, which she reached in April 1944 for a refit and an overhaul.

[4] On 7 June 1944, she transmitted a routine situation report while operating as part of a submarine patrol line south of Truk.

[4] On 10 June 1944, an FM-2 Wildcat fighter from the United States Navy escort aircraft carrier USS Hoggatt Bay (CVE-75) sighted an oil slick on the surface north of the Admiralty Islands which betrayed the presence of Ro-111.

[4] Taylor made sonar contact on Ro-111 and dropped two patterns of depth charges, but her crew observed no sign that they had damaged the submarine.

[4] Taylor then passed through the oil slick and dropped a pattern of depth charges, and at 15:58 her crew heard two large underwater explosions which marked the end of Ro-111.

On 12 July 1944, the Imperial Japanese Navy declared Ro-111 to be presumed lost with all 54 men on board.