Both ships looked like that once completed, a catapult was envised but not yet avaliable at the time of completion.
Kinugasa 1932:
She was the first one to recieve an aircraft catapult and a Nakajima E2N in 1928, but by 1932 a searchlight and two 13mm machine-gun mounts where also added in the bridge area.
Aoba 1937:
Both Aoba and Kinugasa where refitted in 1936-1937, initially a more extensive modification was envised and would have lasted until 1938, but plans does not materialize and a minor one was implemented; a Kawanishi E7K replaced the older Nakajima E2N, two quad torpedo launchers where fitted, four twin 25mm machine guns where placed abreast the funnels and the 13mm machine guns previously placed near the bridge where moved forward of it, 203/50 Type 3 mod 2 barrels replaced the older 200/50 Type 3 mod 1, the 120mm guns where enclosed and upgraded but not replaced, also the hull was bulged to improve stability issues.
Aoba 1941:
By the time the war started some minor modifications where implemented, the guns where slighty modified to increase their elevation and range, a degaussing cable was added and an Aichi E13A superseded the older Kawanishi E7K
Kinugasa 1942:
Aoba 1943:
After suffering heavy damage during the battle of Cape Esperance in October 1942 the destroyed turret 3 of Aoba was plated over and replaced with a triple 25mm machine gun mount, the cruiser then soilered without her aft heavy guns untill august 1943, when a new turret was finally put back in place.
Aoba 1944:
When the battle damage from Cape Esperance was finally repaired other modification where implemented; other than an increase in AA armament the most visible one was the fitting of a tripod foremast to support a type 21 air search radar and it's control room, a type 13 air search was also added on the mainmast.
Aoba 1945:
By the time of her sinking a Type 22 surface search radar had been added, also the AA-suite was further upgraded when the cruiser was relegated to a mere anti aircraft platform in Kure harbor because of irreparable battle damage suffered between late 1944 and early 1945.
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