Five Turrets and a Shooting Problem

Knowing where the target was — and what the ship was doing — turned out to be harder than building the guns.

02The Measurement Chain

When Texas was commissioned in 1914, her primary means of finding range was the optical rangefinder — an instrument that works by measuring the tiny angular difference between the same target seen from two widely separated lenses. The longer the baseline between those lenses, the more precise the reading. Texas shipped rangefinders in her turret roofs and in the conning tower, with the baseline constrained in each case by the geometry of the structure around it. Precision was always a trade-off with physical space.

That range reading then had to be corrected for the firing ship's own speed and heading, for estimated target speed and course, and for all the atmospheric factors already listed. The solution — if "solution" is even the right word for a process still being refined into the late 1910s and through the 1920s — was a director system and the mechanical computing devices that went with it. A director, mounted high in the superstructure where it had the widest view, would observe and measure; the guns in their turrets would be slaved to point where the director commanded rather than where the turret crew could individually see. How rangefinders, directors and the analogue computers behind them actually worked is a subject in its own right, and a deep one.

The barrel is warm from a previous round, which changes its muzzle velocity slightly.

What matters here is that the chain — observation, measurement, calculation, transmission, fire — was only as reliable as its weakest link, and on a steel ship at sea, every link was under stress simultaneously. Electrical runs could be cut. Voice pipes could be jammed. A director crew could be swept away. Texas was built with redundancy in mind: local control from the turrets themselves remained possible, and would be exercised in practice during her long service record.

03The Ship Moves, Too

The final complication was the firing ship's own motion. A ship rolling even a few degrees is continuously changing the elevation of every gun barrel. Fire on the uproll and the shell goes too far; fire on the downroll and it falls short. Learning to time salvoes to the roll cycle — and eventually building gyroscopic stabilisation into the director — was an iterative engineering process that stretched well into the interwar years, the period when Texas herself was undergoing successive modernisations.

Five turrets are the visible part of the system. The invisible part — the chain of measurement, computation and timing that made them anything other than expensive noise — is where most of the real engineering lived.

Written from published engineering and heritage sources. Where a figure is not documented, this archive describes the engineering rather than asserting a number.