(Type B1 submarine - colorized photo by Irootoko Jr)
IJN Submarine I-30:
Tabular Record of
© 2001-2017 by Bob Hackett & Sander Kingsepp
7 June 1939:
Laid down at Kure Navy Yard as Submarine No.
17 September 1940:
Launched as I-35.
31 October 1941:
LtCdr (later Cdr) Kono Masamichi (52)(former CO
of I-60) is appointed the Chief Equipping Officer (CEO).
1 November 1941:
I-35 is renumbered I-30.
28 February 1942:
I-30 is completed and registered in the IJN.
Attached to Kure Naval District.
10 March 1942:
Cdr (Captain, posthumously) Endo Shinobu (52)(former
CO of I-121) is appointed the CO.
27 March 1942:
The German Kriegsmarine naval staff requests the IJN to
launch operations against Allied convoys in the Indian Ocean.
8 April 1942:
The Japanese formally agree to dispatch submarines to
the East Coast of Africa.
11 April 1942:
Departs Kure for Penang, Malaya, carrying an Aichi
E14Y1 Type 0 "Glen"
16 April 1942:
I-30 is assigned to Captain (later Rear
Admiral) Ishizaki Noboru's (former CO of HYUGA) SubRon 8, in the "A" (Ko)
detachment with I-10, I-16, I-18 and I-20 and their support ships, auxiliary
cruisers/supply ships AIKOKU MARU and HOKOKU MARU.
Hashirajima, Hiroshima Bay. Vice Admiral Komatsu, Captain Ishizaki,
their staffs and the midget submarine crews pay a courtesy call on the CINC,
Combined Fleet, Admiral Yamamoto Isoroku (former CO of AKAGI) aboard his
flagship, new battleship YAMATO, moored in Hiroshima Bay. At 1100, the "A"
detachment departs Hashirajima via Singapore for Penang.
20 April 1942:I-30 arrives at Penang.
22 April 1942:
I-30 departs Penang with AIKOKU MARU in advance of the
"A" detachment to reconnoiter selected points on the East African coast for
25 April 1942:
I-30 refuels at sea from AIKOKU MARU.
29 April 1942:
Emperor Hirohito's (Showa) birthday. The "A" detachment
departs Penang, under Captain Ishizaki in his flagship I-10, and sorties towards
the coast of East Africa.
7 May 1942:
Indian Ocean. Gulf of Aden. At dawn, I-30 launches her
floatplane to reconnoiter Aden.
8 May 1942:
After sundown, I-30 launches her "Glen" to reconnoiter
Djibouti, French Somaliland. The floatplane is sighted and comes under fire from
several warships; the mission has to be aborted.
19 May 1942:
I-30 launches her floatplane to reconnoiter Zanzibar and
Dar-es Salaam. The pilot sights one merchant in the harbor and one 4,000-ton
vessel departing. During landing, one of the Glens floats is damaged, but it is
20 May 1942:
I-30 carries out periscope observation of the port at
24 May 1942:
At night, I-30 carries out periscope observation of
Diego Suarez at the northern tip of Madagascar at Antsiranana, on the Indian
29 May 1942:
At night, I-10's floatplane reconnoiters
the harbor at Diego Suarez. The plane sights HMS RAMILLES, an old 29,150-ton
ROYAL SOVEREIGN-class battleship, at anchor in the bay. Also in the harbor are
destroyers HMS DUNCAN and ACTIVE, corvettes HMS GENISTA and THYME, troopship HMS
KARANJA, hospital ship ATLANTIS, tanker BRITISH LOYALTY, 10,799-ton merchant
LLANDAFF CASTLE and an ammunition ship.
Captain Ishizaki orders a midget submarine attack for the next night.
30 May 1942:
I-16 and I-20 launch their midget submarines about 10
miles from Diego Suarez to penetrate the harbor. At 2025, a midget torpedoes and
heavily damages RAMILLES. British corvettes drop depth charges, but at 2120 a
midget from I-20 torpedoes and sinks 6,993-ton BRITISH LOYALTY in shallow water.
(She is later refloated and sunk off Addu Atoll).
Indian Ocean. E of Madagascar. After the midget attack,
I-30 patrols for a short while, then detaches from SubRon 8 and heads west on a
Yanagi* mission. She is attached directly to Headquarters, Sixth Fleet for the
duration of the voyage. The 10th Naval Signal Unit at Singapore relays radio
traffic from the Sixth Fleet to I-30. Cdr Endo's boat remains silent for the
18 June 1942:
Off Madagascar. I-30 is refueled and refurbished by
AIKOKU MARU for the last time.
30 June 1942:
300 miles S of Durban. I-30 is spotted by a South
African Air Force patrol plane, but escapes without damage. Later, she rounds
the Cape of Good Hope and enters the Atlantic enroute to France.
2 August 1942:
I-30 is code-named Sakura ("Cherry Blossom") by the
Japanese and "U-Kirschblüte" by the Germans. She arrives in the Bay of Biscay.
Off Cape Ortegal, she is met by eight Luftwaffe Junkers Ju-88 attack bombers
that provide cover.
5 August 1942:
I-30 is met by eight German M-class minesweepers and
one Sperrbrecher (mine barrage breaker) who escort her to Lorient - the largest
of the five German U-boat bases on the French coast. I-30 is the first Japanese
submarine to arrive in Europe during World War II.
I-30 ties up to a buoy and her crew is transferred by a French tender to
the deck of U-67. Cdr Edo and his crew are greeted by Grossadmiral Erich Raeder,
Oberbefehlshaber (CINC) der Kriegsmarine (OKM), Admiral (later
Grossadmiral/Fuhrer) Karl Dönitz, Befehlshaber der Unterseeboote (BdU) and the
Japanese Naval Attaché to Germany Captain (later Rear Admiral) Yokoi Tadao who
have traveled from their headquarters for the occasion.
The Lorient station band plays martial music and Cdr Edo is decorated
with a German medal. A woman presents him with a bouquet of flowers
traditionally given to successful arriving U-boat commanders. Ashore, U-boat
men, soldiers, nurses, signals women and civilians line up to greet I-30.
Later, I-30's cargo is unloaded. She carries 3,300-lbs. of mica and
1,452- lbs. of shellac for the Germans. I-30 also carries the blueprints of the
Type 91 aerial torpedo, but her own Type 95 oxygen-propelled torpedoes were
removed for the voyage and substituted with 14 Type 89 steam torpedoes so as not
to reveal the Type 95's secrets. (The following year, I-8 is the first IJN
submarine to deliver Type 95s to the Germans.) 
6 August 1942:
An official greeting is held for I-30's crew that
includes a banquet dinner in the Grand Hall of the former French naval arsenal.
The dinner is attended by the I-30's officers, Japanese naval attaches, German
Army and Navy officers and a few civilians.
Lorient is the home of the 2nd U-Flotille "Saltzwedel" commanded by
Knight's Cross with Oak Leaves winner Korvettenkapitän (later Kapitän zur See)
Viktor Schütze (former CO of U-103) and the 10th U-Flotille commanded by
Knight's Cross winner Korvettenkapitän (later Konteradmiral, Bundesmarine)
Günter Kuhnke (former CO of U-28). The German submariners welcome Cdr Endo and
entertain I-30's officers and men. 
Some Japanese and German enlisted men exchange their cap bands, an old
naval custom. Although Japanese crewmen are allowed inside a U-boat where they
take many pictures, no German enlisted men are permitted to board I-30.
Later, I-30 is moved into one of Lorient's 16 bombproof U-Boat pens in
the Keroman bunker. I-30 is refitted and painted the same grey as the U-boats.
Kriegsmarine experts examine her and find that her engine and hull noise levels
are unreasonably high. She is fitted with a a Metox radar detector and a Mauser
"Flakvierling 38" quad 20-mm AA gun replacing her Type 96 25-mm AA guns. 
I-30's floatplane is repaired and painted with false Japanese markings.
During the floatplane's test flights, film footage is shot and later used to
prove the existence of an IJNAF Naval Air Corps operating from French bases.
Endo and his crew travel to Berlin where he is awarded a medal by Adolf
Hitler. Later, he and his crew travel to Paris where they visit the Eiffel Tower
and the Champs-Elysées before returning to Lorient.
22 August 1942:
I-30 departs Lorient. Cdr Endo leaves behind I-30's
E14Y1 floatplane as a "souvenir" of his visit for the Germans.
I-30 carries one Japanese engineer as a passenger. Her cargo includes
blueprints of the Würzburg air defense ground radar and one complete set, five
German G7a aerial torpedoes and three G7e electric torpedoes, five
Torpedovorhalterechner (torpedo data computers), 240 Bolde sonar countermeasure
rounds, rocket and glider bombs, antitank guns, Zeiss anti-aircraft artillery
(AAA) director (fire control system), 200 20-mm AA guns, industrial diamonds
valued at one million yen and fifty top secret "T-Enigma" coding machines.
22 September 1942:
I-30 rounds the Cape of Good Hope. Three days
later, German news agencies announce that a Japanese submarine has joined their
U-boats operating in Atlantic Ocean.
8 October 1942:
Early in the morning, I-30 arrives at Penang. Rear
Admiral Hoshina Zenshiro (former CO of MUTSU), Chief of Ministry of the Navy's
Logistics Section, without consulting the NGS, requests ten T-Enigmas from
I-30's cargo for use by his headquarters at Singapore.
9 October 1942:
The I-30 arrives at Penang where she refuels and
11 October 1942:
In the evening, I-30 departs Penang for Singapore.
13 October 1942:
I-30 arrives off Singapore during the night. Cdr Endo
requests a pilot from the No. 10 Special Base Unit, but fails to contact the
base because his codes are outdated. Endo then decides to independently navigate
the harbor entrance.
At 0930, I-30 arrives at Keppel harbor, Singapore. The 10 T-Enigmas are
disembarked. Cdr Endo dines with the C-in-C, First Southern Expeditionary Fleet,
Vice Admiral Okawachi Denshichi (former CO of HIEI) and the staff of the No. 10
Special Base Unit.
The I-30's navigator receives maps of the mine swept area around
Singapore. At 1609, she departs for Kure. Three miles E of Keppel harbor she
hits a British mine and quickly sinks. Cdr Endo and 96 crewmen are rescued, but
13 men are lost. (In February 1944, off Truk, Cdr Endo is KIA as CO of I-43).
Divers from the No. 101 Navy Repair Unit recover some of the I-30's cargo
including most of the 20-mm guns, TDCs and radar blueprints, but the model of
the Würzburg radar is destroyed and the drawings for it are rendered unusable by
the salt water.
15 February 1943:
Four months later, Tokyo finally informs Berlin of
the loss the 40 Enigma machines aboard the I-30. They also inform the Germans of
the 1 February 1943 sinking of I-1 in shallow water at Guadalcanal that possibly
compromised the Japanese-German joint-use "Sumatra" code.
15 April 1944:
Removed from the Navy List.
August 1959-February 1960:
Salvaged/scrapped by Hokusei Sempaku Kogyo
[1[ When Japan enters the war, the Axis Tripartite agreement
is amended to provide for an exchange of strategic materials and manufactured
goods between Europe and the Far East. Surface ships make the initial "Yanagi"
exchanges, but when that is no longer possible, submarines are used.
 Mica has applications in electrical capacitor devices and shellac is
used in military pyrotechnics.
 Schütze was the fifth leading U-boat "Ace" with 35 ships sunk for
180,073-tons and two ships damaged in seven patrols.
 The roof of the bunker was made of 22-feet of reinforced concrete -
impervious to all Allied bombs except Barnes Wallis' 12,000-lb."Tallboy"
penetrator developed later in the war.
Special thanks go to Dr. Higuchi Tatsuhiro of Japan and Andrew Obluski
– Bob Hackett and Sander Kingsepp
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