are as shown in the table (see opposite page). The continuing drain of squadrons to Coastal Command and the Middle East and the heavy operational losses of 1941 had prevented any build-up in total strength.
Within the overall figures, however, there were some significant trends. The reliable Lancaster had at last appeared and would increase its numbers rapidly. The Lancaster would soon replace the disappointing Manchester and eventually the ageing Hampden which had rendered such good service in 5 Group. Another old faithful which would disappear even earlier was the Whitley; the last Whitley squadron - 58 Squadron - would cease operating with Bomber Command at the end of April on transferring to Coastal Command. The other four-engined types, the Stirling and the Halifax, which had been so slow in developing their strengths would also make steady progress in the coming months. So, while Bomber Command's overall strength would not increase in 1942, its bomb-carrying capacity would.
Alongside the increase in bomb tonnage capable of being delivered, came the first major improvement in navigation. This was Gee, a device which enabled a bomber's navigator to fix his position by consulting an instrument - the Gee Box - which received pulse signals from three widely separated stations in England. Gee computed the difference between receipt of these signals and gave the navigator an instant 'fix'. As it was a line-of-sight device, its range depended on the aircraft's height and range. An aircraft flying at 20,000 feet 400 miles from England could just receive the signals; aircraft flying below that altitude or at greater ranges started to lose the Gee signals because of the curvature of the earth. Gee was thus a navigational device rather than a blind-bombing aid, although some attempts were made to use it for bombing when targets were found to be completely cloud-covered. The major benefit of Gee was in enabling crews to reach the general area of a target when winds encountered were not as forecast and might have taken the aircraft badly off course. The Ruhr, the Rhineland and some of the North Sea ports - Bremen, Emden and Wilhelmshaven - were all within Gee range but the device could still be of use in getting aircraft well started on raids to more distant targets and Gee always helped crews to find their way back to their bases in England. There were high hopes for this device, although it was realized that the Germans would eventually reassemble a set from a crashed bomber and produce a jamming device.
Sir Arthur Harris was fortunate in arriving at Bomber Command at the same time as Gee and the better types of aircraft but he also brought a lively and effective tactical mind and immediately introduced improvements in operational procedures. The first of these were the principle of concentration and the increased use of incendiary bombs. Gone were the days - or rather the nights - when Bomber Command would send its aircraft to two or three targets and spread its bombing over a period of several hours. Harris usually tackled only one main target on nights when operations were considered suitable, still using the moon period. The bombing at that main target was now to be concentrated into a period of two hours or less. The risk of collision was accepted in return for the better use of massed flares, the overwhelming effect of bombing upon a city's fire services and the reduction in the time during which the German Flak defences had the opportunity to engage bombers. The second of Harris's improvements, the use of incendiary bombs, supported the principle that it was easier to burn a city down than to blow it up. Bomber Command was soon to drop its first 8,000-pound blast bomb but, although this was a massive weapon, the more numerous 4,000-pound blast bombs were better for area bombing, especially when supported by a mass of the small 4-pound incendiaries. A standard raid would open with ordinary high-explosive bombs to crater and block roads with fallen masonry to prevent fire engines moving around the city and then the main raid, using blast bombs and incendiaries, would follow. The blast bombs blew off roofs and smashed windows; the incendiaries penetrated the roofs and started fires which were fed by air drawn in through the broken windows. Bomber Command was to become a great fire-raising force.
Harris realized there was little chance of a resumption in general day bombing and 2 Group would be left to languish in minor operations. For various technical reasons the American-built Flying Fortress had failed as a day bomber with the R.A.F., although the Americans would benefit from the R.A.F. experience and later use the Fortress with great success. The Blenheim's operational life with Bomber Command was almost finished but its replacements were never produced in large numbers and 2 Group's days of strength and glory, in Bomber Command at least, were past. Harris would try one small deep-penetration daylight raid by a small force of the new Lancaster aircraft but this experimental raid, to Augsburg, though pressed home with great gallantry, was in reality a costly failure and a sharp reminder that clear weather in daylight still meant death to unescorted bomber aircraft.
The directive on area bombing also released Bomber Command from the restraint order of the previous November and the new commander-in-chief was now urged to make use of Gee in intensive operations. But Harris did not rush blindly into sending the bombers out too often. His first few months were characterized by long periods of steady development, interrupted by bursts of dramatic activity. The Renault works near Paris and the German cities of Essen, Lbeck and Rostock would be Harris's milestones in this first period of night operations. In particular, there would be a series of eight major raids on Essen in the hope that Gee could help to produce effective bombing results on this important but usually haze-concealed target. But there were also long gaps when the weather or the state of the moon was unfavourable. Harris was not prepared to waste effort in conditions which experience had shown to be almost without any hope of success. The overall level of operations and of bomb tonnage in the first three months of Harris's period of command were actually lower than in the equivalent period of the previous year.
The task would not be any easier. The casualty rate for night operations in the next few months would be slightly higher than any previous period of the war and the reports from Germany in this diary will show that there would be as many disappointments in bombing results as successes.
