River-class destroyer


The River-class destroyer was a class of torpedo boat destroyer built for the Royal Navy at the turn of the 20th century, and which saw extensive service in World War I. The class introduced new features to destroyer design, placing a greater emphasis on seakeeping and endurance and less on a high maximum speed in good weather. All the ships were named after British and Irish rivers, and as such were the first Royal Navy destroyer class to be named systematically.

Genesis

The concept for the River class began in December 1900, with a request from John de Robeck, then the senior destroyer officer in the Mediterranean Fleet, for a new class of destroyer with a longer range than the existing "30-knotter" and "27-knotter" types. Robeck's specification called for a range of at a sustained speed of ; the "30-knotter" could only make at its cruising speed of.
Robeck also called for various modifications to destroyer design to help make ships more seaworthy, in particular keeping up their speed in adverse weather conditions. The most noticeable change would be to introduce a raised forecastle rather than an arched turtleback for the hull forward of the bridge, and that the bridge should be placed further aft to keep it clear of spray from waves breaking over the bow. Furthermore, he felt that destroyers should run their speed trials with a more realistic load of fuel and supplies. The "30-knotter" type might have a nominal speed of 30 knots, but even in very good weather this was never achieved in service.
Other officers serving on Royal Navy destroyers made similar observations about their ships. Robeck's commanding officer, Admiral "Jackie" Fisher, drew a comparison with the German, which had impressed Royal Navy officers who had seen it.
In July 1901 the Director of Naval Construction worked on sketch designs for future destroyers, which included many of the features Robeck and his colleagues advocated, as well as a heavier and more reliable kind of engine. The trials speed was initially be, though further requirements for increased strength reduced the speed to. While this speed seemed like a significant reduction, it would be measured with a realistic 95 tons of coal loaded on board, and the better seakeeping properties meant that the new ships would perform better than a "30-knotter" in any seas except for a flat calm.

Design

As with other early British destroyer classes, the Admiralty invited specialist private firms to submit their own designs for destroyers which would meet the specification. The idea was to use the builders' knowledge of building small, fast, ships to help cram powerful machinery into a small hull. For this reason, details of the hull and internal arrangements differed between ships in the class.
Nevertheless, the River class can clearly be distinguished from previous destroyers because of its raised forecastle. Previous British designs that had a low "turtle-back" forecastle, which, although intended to clear the bows, caused them to dig in to the sea, resulting in a very wet conning position. The bridge was also further back than in previous destroyer models.
All ships were coal fired and all but three had triple expansion steam engines; Eden, Stour and Test were powered by steam turbines. Eden was given turbines to test their viability for future destroyer classes, with two propellers on each of her three shafts, to transmit the power at the high revolutions of the direct drive turbines, a feature of the earlier.
By 1906 the Russo-Japanese War had shown that the 6-pounder gun was insufficiently effective, so the five 6-pounders in this class were replaced by three additional 12-pounders, creating an "all big gun" armament.

Performance

With a general increase in size and more solid construction, the Rivers became the first truly oceangoing and useful torpedo boat destroyers in Royal Navy service.
Despite making only 25 knots, the increased seaworthiness meant that they could maintain this speed into a sea and that they remained workable and fightable at the same time. Notwithstanding a variety of design differences, all ships had either two broad funnels or two pairs of narrow funnels.
All ships surviving the war were sold out of service by late 1920.

Ships

Thirty-four ships were ordered - ten ships under the 1901-02 Programme, eight ships under the 1902-03 Programme, and fifteen ships under the 1903-04 Programme; two additional vessels were purchased in 1909 under the 1908-09 Programme.