The Italian submarine Leonardo da Vinci and the multinational Monsoon Group at Penang show how submarine operations extended far beyond the Mediterranean and Atlantic. German, Italian, and Japanese boats operating in the same region complicated identification for Japanese forces, and British submarines could exploit the resulting hesitation. Merchant traffic that felt relatively safe after rounding Africa could still face attacks while heading toward Suez, India, or Singapore, making even a few long-range boats operationally disruptive. British and Dutch shortages of available submarines also limited opportunities to contest Japanese operations such as Operation C.
Notable Point · 1:33:18-1:39:29
The overlooked submarine war in the Indian Ocean
Long-range Axis boats made the Indian Ocean an important but underappreciated threat to the routes around Africa, India, and Singapore.
Allied ConvoysAllied SubmarinesCape RouteConvoysDutch NavyGerman NavyI 27I 37IndiaIndian OceanIndian Ocean Raid (1942)Italian NavyItalian Submarine Leonardo da Vinci (1939)Japanese NavyLong Range SubmarinesMadagascarMaritime TradeMerchant ShippingMonsoon GroupPenangRules Of EngagementSea Lines Of CommunicationSingaporeSouth AfricaSubmarine BasingSuez CanalSurface RaidersU-181U-511World War II