Flags captured from the Japanese Type A kō-hyōteki midget submarine HA-19 at Pearl Harbor in the days immediately after the attack on 7 December 1941, one of five luckless vessels whose part in the attack (likely) yielded nothing.
The third Japanese Type A boat spotted by American forces in and around Pearl Harbor– after one famously sunk by the old four-piper destroyer USS Ward (DD-139) and another less known sub dispatched by the newer USS Monaghan (DD-354) on the morning of that infamous day– the abandoned HA-19 was dubbed “Midget C” when Army Air Corps pilots spotted her grounded on an offshore reef near Waimanalo on 8 December after the craft’s scuttling charge failed to go off.
Washed ashore near where Sakamaki, the only survivor of the hapless vessel, swam ashore, HA-19 was captured in remarkable condition and towed from the surf zone by an Army tractor.
Other items besides the flags were recovered, including a map of the harbor with HA-19‘s planned route.
Disassembled in three large pieces and inspected, HA-19 served as a traveling war bonds trophy before being put on outdoor display for 40 years before the boat was semi-restored and moved inside the Nimitz Museum (National Museum of the Pacific War) in Texas a while back, and it is still there.
As for Sakamaki, he was not only the sole survivor of his boat but was also the lone survivor of the crews of the five Japanese midgets that participated in the attack.
Four of the five Pearl Harbor midget submarines have been found– all lost before they could penetrate the harbor– and, as noted by NHHC, could be the most controversial and a missing piece of naval history:
One of the five Pearl Harbor midgets is still unaccounted for. Recent studies of Pearl Harbor attack photograpy have led some observers to argue that one of the midgets was in place off “Battleship Row” as the Japanese torpedo planes came in, and may have fired its torpedoes at USS Oklahoma (BB-37) or USS West Virginia (BB-48). This contention is still controversial, but, if it is true, the “missing” Type A midget submarine may lie undiscovered inside Pearl Harbor.