127 mm Dual AA Gun
The largest gun in the Japanese arsenal was the Type 89 127 mm/40 caliber dual-purpose twin-mount antiaircraft gun. It was originally designed as a naval gun that was to be mounted on I.J.N. cruisers. On Betio the Japanese had emplaced four of these guns. Two guns were positioned on the north shore facing the lagoon and were located about four hundred yards east of the airfield. The second pair were facing the open sea on the southern beach, about five hundred yards east of the 8 inch "Singapore guns." During the invasion these guns were used with great effect firing horizontally at LVTs and Higgins Boats. For ammunition expenditure of these guns for the days before the invasion see Japanese Ammunition Expenditure table.
|Year Introduced : 1929|
|Caliber : 127 mm|
|Barrel Length : 5 m (L40)|
|EL Angle of Fire : -8 to +90 Degrees|
|AZ Angle of Fire : ?|
|Shell Weight : 23 Kg|
|Muzzle Velocity : 720 m/sec|
|Weight : 20.3 ton|
|Range : 9,300 m|
This picture of gun crew drill was recovered from a Japanese camera after the battle.
Aerial view of the southern two gun emplacements facing the ocean.
Above and below are the lagoon side gun emplacements.
A type 89 emplacement before the invasion. Click here for a larger image.
Front and side view of the deadly Type 89 AA gun.
Breach mechanism with former gun crew.
Special thanks goes to Taki of the Imperial Japanese Army Website for providing pictures and information.
copyright 2000 T.O.T.W.
Created 19 March 2000 - Updated 13 October 2001