|The first four ships (Z1 – Z4), designated Type 34, were completed with a straight stem and trials soon proved that the design of the bow left a lot to be desired, as
the forward part of the ship was very wet. They also had a round front face to the bridge. The bow of the first four was redesigned with an angled cutwater, raised
forecastle and bow sheer and a square bridge added to for more space for bridge personnel. The next twelve were built with these modifications and designated Type
34A. Two Type 34 were laid down in October 1934 and the second two in January 1935. The twelve Type 34A ships were laid down between July 1935 to
November 1935. The design was larger in size and heavier in displacement and stronger in armament than most contemporary designs, although the French
Mogodor class was even larger. However, the only real innovation was the use of the high pressure boilers. The destroyers were far ahead of most contemporaries
in terms of anti-aircraft armament. At a time when foreign designs relied on machine guns for AA, the Type 34 mounted two twin 37mm AA mounts and six 20mm
AA guns. The ships were 390-feet 5-inches oa for Z1 through Z8 and 397-feet oa for Z9 through Z16. Beam was 37-feet. Displacement ranged between 2,171-tons
to 2,239-tons standard (3,110-tons to 3,160-tons full load. Total armament was five 5-inch (5x1) guns, four 37mm AA guns (2X2), six 20mm AA guns (6x1), eight
21.7-inch torpedoes (2x4) and 60 mines. The high pressure steam plant of six Benson boilers drove two shafts and developed 70,000shp (when not broken) with a
maximum speed of 38-knots. Range was 1,900 nm at 18-knots. The Type 34 and 34A ships were given names. In a harbinger of things to come, the Bruno
Heinemann (Z8) was completed was completed with four 5.9-inch guns (150mm) instead of the five 5-inch guns. She was a test unit to see if destroyers gun carry
a heavier main battery successfully. However, the actual tests were done at low speeds in good weather and produced grossly over-optimistic reports.
The next design was called Type 36. It was basically an improvement of the previous Type 34 design with reduced top weight achieved through the reduction in
height of the forward funnel and amidships superstructure. The hull was lengthened and beam slightly increased with better underwater hull lines making the class
better sea boats than the Type 34/34A ships. Six ships were in the class, all launched with names. The first three, Z17 through Z19 were completed with a bow
design of the Type 34A but for the last three, Z20 through Z22, were given clipper bows, further increasing their length. Steam pressure was reduced by switching
to Wagner high pressure boilers operating at 850psi but even with a drop of more than 500psi, these boilers were still plagued by failure and breakdowns. Z17 to
Z19 were laid down in September and October 1936 but there was a slight delay in start up for the next three because of the redesign with the clipper bow. Z20
through Z22 were laid down September 1937 through January 1938. The only change in armament over the Type 34 ships was the addition of a seventh 20mm gun.
Length for Z17 through Z19 was 403-feet 6-inches and for Z20 through Z22 410-feet 1-inch because of their clipper bows. Beam for all units was 38-feet 8-inches.
Displacement ranges from 2,411-tons to 2,449-tons standard and 3,415-tons to 3,469-tons full load. The Wagner boilers and turbine plant produced the same power
and speed as the Benson boiler plant of the Type 34 ships. Range was slightly increased to 2,100nm at 18-knots by increased fuel oil bunkerage.