Another a repost of the original part one with an extra drawing to cover the 1930-1940 timeframe
Okaze Class Destroyer (Part 1, 1923-1940):
To supplement the 15 smaller Shion class Destroyers the naval staff reordered the last 6 ships of the canceled Sato class to a larger design: the Okaze Class. As for the Shions, in order to have the new units in service as soon as possible Okaze and her sisters were just slightly modified Kamikaze class Destroyers. Modifications included the addition of walkways that linked the bridge with the middle gun and searchlight platform, and a slighly different and better enclosed bridge structure. Armament consisted of four Type3 120mm/45 guns in single mounts, six 533mm torpedo tubes in three sets of double launchers and two 7.7mm machine guns. The ships were equipped to carry up to 20 mines if needed. Four Kampon boilers powered two-shaft geared turbines at 38,500 shp, giving the ships a top speed of 37knots and an endurance of 3.600 natical miles at 14 knots.
The lead ship, Okaze, was laid down in august 1922 and commissioned by fall 1923. Her perfomance was considered so satisfactory that another twelve units were immediately ordered, bringing the class to 18 ships. At the cost of 47 more tons in displacement when compared tot he Sato class (and 73 to the Kuchikukan 14 units), the Ozake sported the same armament but enyoyed 1,5 times more range and a nearly 3-knots higher top speed, all in a shorter and sturdier hull, more suited to blue water operations.
All ships were built between 1922 and 1929: 7 At Kumoi Arsenal, 4 at Toumachi Naval Arsenal, 3 at Kousaten Navy Yard, 2 at Hoshiguma Navy Yard and one at Yamatogawa Shipyards. Finally, one last unit, Mima, was ordered abroad in Japan as all available shipyards were full with construction. Mima was laid down at Yokosuka in september 1923, but was destroyed during the Grat Kanto Earthquake and had to be laid down again, she was ultimately commissioned in 1926.
Six units, Meira, Kana, Rikako, Chiyuri, Yumemi and Kurumi, recieved the newer 120mm/45 Type10 guns, which, having a maximum elevation of 70° effectively served as bot surface and AA guns. Also, they sported depth charges instead of the mine-laying gear of the earlier sisters.
Ruukoto, the las unit to be commissioned, in 1929, recieved some more modifications, beign given a larger bridge and an expanded searchlight/rangefinder platform. RDF equipment was added at midship and the bridge rangefinder replaced with a newer model.
The ships formed 5 Kuchikutai units (three 4-unit and two 3-unit) up to the mid 30's. Then, starting in 1936, they entered the yards for their pre-war refit: All had a late-model RDF equipment fitted, the bridge wings enclosed and two single 25mm machine guns fitted. Both funnels were increased in height to improve smoke-clearing issues. The depth charge complement was also notably increased and an hydrophone installed.
Despite beign of the same age of the Shion class, the Okaze were still considered capable enough to be rated as first-rate ships. Forming Suirai Sentais 5,6,7 and 9 led by Light Cruisers Asakura, Okazaki, Kompaku and Otonase, their role in an eventual war according to Koko no Kaigun strategy was to operate as anti-submarine units close to home waters or in support of larger naval operations.
Ships in class: (laid down-launched-commissioned - fate)
okaze 1922-1923-1923 - ?
tsumujikaze 1922-1923-1923 - ?
norio 1923-1924-1924 - ?
sachio 1923-1924 1925 - ?
kawatake 1923-1924-1924 - ?
yoshizake 1923-1924-1925 - ?
mima 1923-1926-1926 - ?
kikuri 1923-1924-1925 - ?
konngara 1924-1925-1926 - ?
genjii 1924-1925-1926 - ?
rika 1924-1925-1926 - ?
meira 1925-1926-1927 - ?
kana 1925-1926-1927 - ?
rikako 1925-1927-1927 - ?
chiyuri 1925-1927-1927 - ?
yumemi 1926-1927-1928 - ?
ruukoto 1926-1928-1929 - ?
kurumi 1926-1927-1928 - ?