Iron Knight sunk by Japanese Submarine I-21 in February 1943, wreck found June 2006

We gratefully aknowledge the quotes from John Stone, and other paraphrasing of Craig Allen's script, from the ABC Stateline, ABC News Canberra.

The BHP iron ore carrier Iron Knight built in Glasgow in 1937, and commanded by Captain Ross, was part of a 10 ship convoy escorted by two RAN Corvettes, Townsville and Mildura, sailing down the east coast of New South Wales.

Iron Knight
Iron Knight

They were off the fishing port of Bermagui when the Japanese Submarine I-21 sighted convoy funnel smoke 40 miles away. She tracked the convoy to fire a torpedo which passed under Townsville, but found its target on the leading ship of the starboard column Iron Knight at 0230 ( 2.30 AM ) on the 8th. of February 1943. She sank in less than 2 minutes taking 36 crew with her.

History of Japanese Submarine I-21.
This I Class submarine completed at Kawasaki, Kobe on the 15th. of July in 1941, and joined SubRon 1's. Submarine Division 3 in the 6th. Submarine Fleet, Commander Matsumura Kanji being her first CO. I-21 was part of the strike force assigned to attack Pearl Harbor on 7 th. of December 1941, her place ahead of the Carriers acting as a lookout with sister boats I-19 and I-23.

After this sneak attack at Pearl, on the 23rd. of December, I-21 sank the 8,271 ton, Union Oil Company tanker Montebello, enroute from California to Vancouver, her crew abandoning her in four lifeboats.

Early in 1942, this submarine returned to her homeland, then to operate in the Pacific Ocean, and sinking the 7,176 ton Liberty ship John Adams on the 5th. of May, she was carrying 2,000 tons of gasoline, and went up with a big bang! This was the first Liberty ship to be sunk in the Pacific.

Two days later whilst on the surface, I-21 used gunfire to dispose of the Greek 4,641 ton vessel, Chloe.

Model of B Class Japanse Submarines. I-21 was one of the 20 boats in this class
Model of B Class Japanse Submarines. I-21 was one of the 20 boats in this class

I-21's Glen Floatplane flies reconnaissance flights.
Over May of 1942, Warrant Officer Ito, the pilot of I-21's Glen floatplane, flew missions over Suva, then Auckland, where the NZ authorities convenienly switched on their landing lights as he flew low over their runway. Lasly he flew over Sydney Harbour with his navigation lights switched on. Here he sighted the US heavy cruiser Chicago which he wrongly took to be a battleship, probably confused by her heavy top hamper. On landing alongside his mother submarine lurking outside Sydney Harbour in quite heavy seas, the Glen capsized, and had to be scuttled.

Japanese Midget Submarines attack Sydney Harbour, 31st. May/1st. June 1942.
Sister Japanese Submarines, I-22, I-24 and I-27, all launched their midget submarines from their position off Sydney Heads on the last day of May 1942, and these three Midgets, each with a two man crew, sneaked through the opening between North and South Heads to try and penetrate the boom nets strung from the north side of the Harbour to the south side.

Two made it through the gate opening into the harbour, probably following a Manly Ferry, one became entangled in the anti-submarine boom mesh, a second, was sunk in Taylor Bay, and the third Midget A, under the command of Sub Lieutenant Ban fired a torpedo at USS Chicago, missed, to finish up exploding on the stone wall at Garden Island. This explosion destroyed the old wooden ferry, HMAS Kuttabul, killing 21 sailors, as it was used as an accommodation facility.

HMAS Kuttabul old accommodation ferry sunk by Midget SAubmarine attack, Sydney Harbour 31st.May/1st. June 1942
HMAS Kuttabul old accommodation ferry sunk by Midget Submarine attack,
Sydney Harbour 31st.May/1st. June 1942

That night I was a Sub Lieutenant RAN in the heavy cruiser HMAS Canberra, secured to No. 1 Buoy in Farm Cove, close to the now Opera House site.

Ban was unlucky not to sink USS Chicago, he most likely set his torpedo too deep, anticipating his target to be a battleship, as reported by Ito after his flight over the harbour. That momentous night, our defence some how muddled through, but we were indeed lucky to get away with it.

Sub Lieutenant Ban managed to exit his Midget from Sydney Harbour, but did not make it back to his mother Submarine, and his Midget has still not been found to this day. As all the I Boats failed to recover their charges, they took off to continue their maurading against our merchant shipping.

Japanese Midget Submarine recovered Sydney Harbour June 1942
Japanese Midget Submarine recovered Sydney Harbour June 1942

Attack on Newcastle.
On the 8th. of June, at 0215 ( 2.15 AM ) I-21 fired on the Newcastle Dockyard, using 28 High Explosive and 8 Star shells.

I-21 sinks merchant ship on the 12th. of June.
The 5,967 ton Panamanian registered ship Guatemala in convoy from Newcastle to Whyalla in South Australia, loaded with 4,200 tons of coke was sunk by I-21, on the 12th. of June, and her crew were picked up by HMAS Doomba.

I-21 returns to Japan, and thence to patrol the Pacific.
By mid July 1942, I-21 is back home in Japan for a refit, and then in August having joined the 6th. Fleet Submarines at Truk, she goes on patrol in the Solomons area where US Marines had landed at, and occupied both Tulagi and Guadalcanal islands.

Serving in HMAS Canberra, I had been sunk at the Battle of Savo Island on the 9th. of August 1942, in the early stage of this operation.

In October, I-21 fired 6 torpedoes at a Colorodo Class battleship, one explosion was heard, but 3 of her torpedoes stuck in their tubes, but were later safely extracted.

The Liberty ship Edgar Allen Poe is hit by a torpedo fired from I-21, and her crew abandon her, she is then towed to Noumea but is deemed to be a write off.

Over December 1942 this submarine is employed running in supplies to Japanese troops still holding out on Guadalcanal.

Australian waters.
January 1943, finds I-21 off the east coast of Australia looking for victims. In the Tasman Sea on the 18th. of January, the 2,621 ton Australian freighter Kalingo was despatched and 2 of her crew died, next came the US tanker Mobillube of 10, 222 tons. Although she is towed into port by the salvage tug St Aristelli, the tanker is deemed to be a write off.

Off Newcastle on the 23rd of January, the Liberty ship Peter H. Burnett crammed full with 18,154 bales of wool is attacked by I-21, she is towed to Sydney by the US mine sweeper Zane, and the Australian Corvette Mildura, and the cargo is saved, but the ship is a loss.

Peter H.Burnett under tow after she was torpedoed by I-21
Peter H. Burnett under tow after she was torpedoed by I-21

Reconnaissance flight over Sydney.
Once again, the Glen floatplane from I-21 undertakes a recce flight over Sydney Harbour to report a heavy cruiser and smaller craft there.

Attack on Iron Knight.
On the 8th. of February 1943, off Montague Island on the NSW coast, I-21 spotted smoke about 40 miles away, it emanated from Convoy OC 68, comprising ten ships escorted by two Australian Corvettes, Townsville and Mildura.

The submarine steamed into firing range and let go with a torpedo, which passed under Townsville, but went on to hit the BHP ore carrier, Iron Knight making for Whyalla. Laden with iron ore she sank like a stone in under two minutes, only 14 of a crew of 50 survived, taking to a raft to be rescued by the French Destroyer Le Triomphant.

After the Canberra was sunk, I came home, had two weeks survivor's leave, to be sent off to join the old light cruiser HMAS Adelaide as one of her watch keeping officers, we were based at Fremantle undertaking convoy escort work in the Indian Ocean. At that stage, Le Triomphant was also based at Fremantle, our sailors nicknamed her the Reluctant Dragon, WHY? because when ordered to sea she so often pleaded boiler problems, not seemingly anxious to be at sea. She also carried live pigs on board as potential fresh meat, and to be windward of her was not pleasant because of the smell emanating from her live cargo.

Smoke from convoy ships.
The CO of I-21, noted in his log that the funnel smoke from Convoy OC 68 had been sighted at a distance of 40 miles, and that in his experience such smoke often gave him the first indication of a potential victim close by.

During all of WW2, many a merchant ship came to a nasty end through emitting black funnel smoke, or ships in the same convoy did not adequately control the smoke belching from their funnels. A dead giveaway to any lurking submarine, be it German, Italian, or Japanese.

Final victim off Australia of I-21.
The US Liberty ship Star King loaded with 7,000 tons of Army supplies became the last ship off Australia to be sunk by I-21 on the 10th. of February, she was hit by 2 of the 4 torpedoes fired, and HMAS Warramunga, an Australian built Tribal Class destroyer tried to take her under tow, but the ship sank, but her crew were rescued by the destroyer.

On the 16th. of March 1943, Commander Matsumura was relieved by Commander Ineda Hiroshi, but as a Captain in I-177, he is killed in action. Posthumously, he received a double promotion to Vice Admiral.

Last victim of I-21.
Under the command of Commander Ineda Hiroshi, on the 11th, of November I-21 made her last kill, sinking the US freighter Cape San Juan, she was on her way to Townsville Australia, loaded with 1,348 American troops, 16 of whom died from the torpedo attack, and another 114 drowned after abandoning ship.

Death of I-21.
I-21 met her end on the 4th. of February 1944, sunk by USS Charlotte ( DD 581 ) and USS Fair ( DE 35 ) in the vicinity of the Marshal Islands.

Wreck of Iron Knight found in June 2006.
Bermagui, a NSW fishing port some 5 hours drive south of Sydney is home for a number of commercial fishermen. Over a number of years their fishing nets had been snagged on an underwater obstruction, these locations were shared with the Sydney Project Dive Team which recently decided to investigate what was causing this loss of nets.

Fishermen's net snagged on the bridge of Iron Knight.
Fishermen's net snagged on the bridge of Iron Knight.

Thus in June 2006, a team including Samir Alhafith, ( who was born in Bagdad, but migrated to Sydney as a teenager where he learned his diving craft around Sydney Harbour, filming its wonderful underwater wild life.) descended 125 meters off Bermagui to discover Iron Knight, 63 years after her sinking.

Dive photos by Samir Alhafith and other members of the Dive Team, publised with his permission. This is Samir at the ladder
Dive photos by Samir Alhafith and other members of the Dive Team, publised with his permission.
This is Samir at the ladder

In discussing this dive Samir told me: " Water visibility was 50 meters, we had zero current and took just 4 minutes to get down, and then spent 16 minutes on the actual wreck. This was followed by 4 hours of  decompression time. It was a magical dive and by far one of the best wreck dives we did anywhere."

Ship's gun mounted to give her some protection
Ship's gun mounted to give her some protection

Crew of Iron Knight.
From a crew of 50, 36 died when the ship sank, and of the 14 who survived in 1943, only John Stone still survives. It took but 2 minutes for his ship to sink. He said:

" I never got over the side, it just went from under me, and I remember being sucked down with it. How I came up I don't know, I grabbed a smoke flare and thought if I can hold my breath long enough, I will definitely come up to the top, and I DID.

When I did come up, I did not know where I was, I could not see a soul, and called out anyone there! They were a bit away from me on a raft, and I managed to swam over.

You must count yourself lucky. ( interviewer )


Starboard side of the ship's bridge
Starboard side of the ship's bridge

Family Members of the Iron Knight crew.
Relatives of those who were lost in the Iron Knight have only been able to guess where their loved ones may lay. Now at last, they are aware for certain where her wreck is located. Recently a group of relatives made a bumpy and emotional journey to sea from Bermagui to over the wreck site where they cast 36 poppies on the ocean, one for each crewman who died back on the 8th. of February 1943, now over 63 years ago.

The relatives cast 36 poppies into the Pacific Ocean. one fo each sailor who died.
The relatives cast 36 poppies into the Pacific Ocean. one fo each sailor who died.

The sea is forced to give up one more of it secrets so tightly held these past 63 years. The Iron Knight lies 135 meters below the surface of the Pacific Ocean, fishermen's nets snagged on her bridge, proved to be the key to her discovery.

The Australian Federal Government has declared this vessel an Historic Shipwreck under their Historic Shipwrecks Act, thus protecting the remains of the 36 crew from becoming exploited from anyone who dives on the wreck. May they long rest in peace.

Modern diving methods combined with the skill of the Sydney Project Dive Team have been successful in unlocking yet one more previously unsolved WW 2 shipwreck.


Details of the 20 B Class Japanese Submarines.

Units 20 (one survived)
Ships I-15, I-17, I-19, I-21, I-23, I-25, I-26, I-27, I-28, I-29, I-30, I-31, I-32, I-33, I-34, I-35, I-36, I-37, I-38, I-39
Year(s) Completed 1940-1943
Displacement 2,584 tons / 3,654 tons
Dimensions 356.5 ft x 30.5 ft x 16.8 ft
Machinery 2 diesels: 12,400 hp
electric motors: 2,000 hp
Speed 23.5 knots surfaced / 8 knots submerged
Range 14,000 nm @ 16 knots
Armament 6x533mm TT fwd + 1x14cm/50 cal. (17 Torpedoes) + one seaplane
Max. Depth 100 m (330 feet)
Crew 94 officers and men


Here are the dive photos by Samir Alhafith and other members of the Dive Team, publised with his permission.

The image ( 1 ) is Samir at the ladder. The net shows the Fishermen's net snagged on the bridge of Iron Knight. The gun is the ship's gun mounted to give her some protection. Starboard side of the ship's bridge. The relatives cast 36 poppies into the Pacific Ocean. one for each sailor who died.

We gratefully aknowledge the quotes from John Stone, and other paraphrasing of Craig Allen's script, from the ABC Stateline, ABC News Canberra


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