Flaws in Japanese tactics Attack on Sydney Harbour

m-21 being raised floating crane on 10 june 1942



the wreckage of m-21

the main flaw in japanese plans use of midget submarines primary attack. midget submarines intended operate during fleet actions: released modified seaplane carriers run amok through enemy fleet. concept went out of favour changing japanese naval thinking , experience led recognition naval warfare centre around carrier-supported aerial combat. result, midget program s focus changed infiltration of enemy harbours, attack vessels @ anchor. concept failed during attack on pearl harbor, midgets had no effect, , tying 11 large submarines 6 weeks in support of further midget submarine attacks on sydney , diego suarez proved waste of resources.

moreover, failures @ sydney harbour , diego suarez demonstrated improvements midget submarines made after pearl harbor had not increased overall impact of midget program. modifications had various effects. ability man , deploy midgets while mother ships submerged prevented army coastal radars detecting mother submarines. however, midgets still difficult control, unstable, , prone surfacing or diving uncontrollably. these manoeuvrability issues contributed m-14 s entanglement in anti-submarine net, , repeated detection of m-21 , m-24.

beyond use of unreliable midgets, historians have identified areas in plan of attack japanese have done more damage. if japanese midget submarines had conducted simultaneous, co-ordinated attack, have overwhelmed defences. chance more damage came following destruction of kuttabul, when several naval vessels headed sea, including uss chicago, uss perkins, dutch submarine k-ix, hmas whyalla, , hmis bombay. 5 mother submarines en route port hacking recovery position, , although sasaki s plan @ pearl harbor had been leave submarines @ harbour mouth pick off fleeing vessels, did not repeat tactic.