CHAPTER 13
Pathfinders and Raids on Italy

BY the middle of 1942 the pattern of future Allied strategy was more clearly defined. The Japanese attacks in Burma and the Pacific were to be held and an offensive launched in Europe against Germany. But poverty of equipment, particularly in landing craft, and the short period remaining when the weather would allow such vessels to cross the Channel, ruled out a direct assault on the Continent during 1942. It was also doubtful whether the Allied air forces could achieve and maintain the local air superiority necessary to establish an invasion bridgehead and cover the advance from it. A landing in North Africa was finally accepted as the only operation that could be undertaken immediately with fair prospect of success. Although distant from the heart of Germany, such an assault would at least serve to divert some of the pressure from the Red Army and at the same time materially improve the situation in North Africa. But the build-up for a cross-Channel invasion was now inevitably delayed, and it remained for Royal Air Force Bomber Command to continue the direct attack on Germany. This aerial offensive could still be sustained only by night but there was confidence that, with the aid of the scientists, many of the problems associated with night raids would soon be solved and the bombing made more concentrated.

During July 1942 major attacks by Bomber Command were directed against Bremen, Wilhelmshaven, Duisberg, Saarbrucken and Hamburg. The latter raid, on the 26th of the month, was the most successful, daylight reconnaissance confirming crew reports that substantial damage had been inflicted. An attempt two nights later to follow this success with another attack employing the whole resources of the Command was frustrated by deteriorating weather at bases in England. Many aircraft had to be recalled and other sorties cancelled. Better fortune attended a raid by 480 aircraft on the night of 31 July against Dusseldorf, on the edge of the Ruhr, almost as important a target as Essen. In this and a subsequent attack ten days later the town was as extensively damaged, in proportion to its size, as Cologne. The weather on both occasions was exceptional, with no cloud and little haze in the target area. Only in the later stages of the attacks did smoke from the fires hinder identification of ground detail.

But the thousand-bomber scale of attack could not be repeated, and the weight of these raids in July and August proved insufficient to saturate the enemy’s expanding defences. The rate of operational losses, in which there was a sharp increase during these months, showed clearly that the enemy was gaining a considerable degree of tactical superiority as a result of his counter measures. The German anti-aircraft fire, assisted by radar, had become more deadly, and there had been a steady reinforcement of the night fighter squadrons with an increase in the number of their ground control stations. Another significant development was the removal of nearly all the searchlights previously arranged in a belt along the frontier and their concentration in the actual target areas, where they produced such a dazzling effect that it became difficult for the bomber crews to identify ground detail and locate their aiming point. This removal of the searchlights from the frontier caused no hardship to the enemy defence since they were no longer needed to assist air interception. The German night fighters were now being fitted with airborne radar, and they became a greater menace to the British bombers both during the flight over enemy territory and in the actual target area. A deadly form of attack was often adopted in which the fighter climbed steeply until it got under the tail of the bomber. The fighter then opened fire at close range and continued to fire while climbing more steeply. It was extremely difficult to see the enemy’s approach against the dark background below the tail of a bomber, and gunners were frequently taken by surprise. A weaving and twisting form of flight was developed as evasive action in which the bomber was repeatedly banked so that the area below it could be searched. But even so the German night fighters continued to take a heavy toll.

By the end of August 1942 it was evident that, in spite of very determined efforts by crews to find and attack their objectives, the damage being inflicted on German targets was insufficient to compensate for the heavy losses incurred. During the last weeks of that month there came a further serious setback when crews reported that the Germans had commenced jamming the transmissions from the Gee stations in Britain, thus depriving the bombers of their most effective aid to navigation. For Bomber Command to recover the initiative several things were urgently needed. First of all, some way had to be found of breaking the very efficient control of the German night fighters by their ground stations. Counter measures had already been devised by the scientists and the main difficulty was in getting the equipment, although there was also considerable concern lest the Germans should turn these weapons against the defences of Great Britain. A second requirement was to secure greater concentration of bombing under less favourable conditions. page 275 The essence of this problem was to ensure that the leading aircraft should be able to draw the rest to the aiming point by marking it unmistakably, not merely by fires started with incendiary bombs, since realistic decoys and the jettisoning of incendiaries near the target by aircraft which got into difficulties rendered this method of marking most unreliable. Experiments were already being made, but it was some time before a suitable marker bomb was developed and not until January 1943 was it available for operational use. Nor were the new radar aids to replace Gee ready until the same month.

In the meantime, the idea of having separate target finding units had been accepted,¹ and the Pathfinder Force came into being during August 1942, under the command of an Australian pilot in the RAF, Group Captain D. C. T. Bennett. Bennett was a profound student of navigation, with outstanding technical knowledge and operational ability. During the early part of the war he had taken a major part in starting the trans-Atlantic ferrying of aircraft. Then he commanded a Halifax squadron, was shot down while attacking German warships in a Norwegian fiord, escaped to Sweden and, after many adventures, eventually returned to England. His Pathfinder Force was to contain picked crews, highly skilled in navigation and target location, whose function would be to precede the main force and create for it an unmistakable beacon as a focus for the attack. Certain advantages were anticipated from having these crews in a separate formation. By concentrating on their special role, tactics could be developed more quickly. In addition, the aircraft of the small leader force could be equipped with the first samples of new aids and devices and the advantage obtained by the bomber force as a whole long before production would permit of general distribution.

Upon the crews from the pathfinder units now fell the difficult tasks not only of locating and illuminating the target but also of marking the aiming point effectively. The basis of most of the target marking technique thus far employed was visual marking of the aiming point in the light of flares or in moonlight, and at first this was continued by the pathfinder units. But by the end of September tactics had been evolved whereby the pathfinder force detailed for any particular raid was divided into three parts. The first section, designated ‘finders’, on reaching the target dropped long sticks of flares right across it. They were closely followed by the ‘illuminators’, who searched for the aiming point itself and dropped much shorter sticks of flares for the benefit of the ‘markers’. These aircraft then came in and tried to release their incendiary bombs on the aiming point, marking its position for the benefit of the main force which was timed to arrive shortly after- wards. As these tactics became established, bombing raids were planned according to a more or less definite pattern, the first phase being the finding and marking of the target by the pathfinder crews, followed by the build-up of the attack by a fire-raising force and, finally, the bombing by the main body of bomber aircraft. Following upon the successful fire raids earlier in the year, the bomb loads now ordered for attacks on German cities almost invariably consisted of a large proportion of incendiaries in addition to high-explosive blast bombs.

The first attack led by the Pathfinder Force was launched on the night of 18 August 1942 against Flensburg, where there were large submarine building yards. Raids on such naval targets were now being made with increasing frequency and, together with aerial minelaying operations, formed the major part of Bomber Com- mand’s contribution to the war at sea. Subsequent targets to which large forces were led by the pathfinders included Frankfurt, attacked by 226 bombers on 24 August, and Kassel, raided two nights later by 340 aircraft. On the latter occasion the Pathfinder Force consisted of eight Stirlings, eleven Lancasters and fourteen Wellingtons, which paved the way for a very successful attack. German police records reveal that fires were started throughout the town, and the Henschel aircraft factory, a large railway construction firm and the important Fieseler Works, manufacturing aero-engines, were all heavily damaged. A few nights later considerable destruction was inflicted upon Nuremberg and Saarbrucken. In September came heavy attacks on Karlsruhe, Bremen, Duisberg, Dusseldorf and Essen, together with smaller raids on the submarine building yards at Lubeck and Flensburg and against Munich and Saarbrucken. Several of these raids caused notable destruction. At Karlsruhe some sixty acres at the east end of the harbour were laid waste, while the raid against Dusseldorf on 10 September devastated over one hundred acres in the town, including numerous warehouses and industrial premises. October raids on Osnabruck and Kiel also caused fairly widespread damage. On the other hand, there were occasions when heavy cloud or thick haze prevented the majority of crews from seeing the pathfinder markers and scattered bombing resulted. This occurred during attacks on Bremen and Essen in September while, at the beginning of the same month, the main weight of a heavy attack intended for Saarbrucken fell upon the neighbouring town of Saarlautern. Again in the middle of October, an attack on Cologne by a force of 289 bombers was largely frustrated by high winds and rough weather which caused the marking to go astray. Most of the bombs fell to the south-west of the city.

Nevertheless, in spite of such failures, there was a marked improvement in night bombing operations following the introduction of the Pathfinder Force, and photographs taken during the attacks and in subsequent daylight reconnaissance showed a considerable increase in the concentration of the bombing round the aiming point. Unfortunately, however, a new source of error was also revealed. On several occasions when there had been difficulty in placing the markers correctly, the whole concentration had been misplaced. Any errors in marking were, in fact, perpetuated by the whole force, since the crews of the main bomber stream were now ordered to aim at the markers dropped by the pathfinders instead of trying to find the aiming point themselves.

That the pathfinder crews sometimes found it hard to locate the aiming point was not surprising since, apart from enemy gunfire and searchlights, there were many technical difficulties still to be overcome. The existing flares produced an upward glare which not only dazzled the air bomber and made identification of ground detail harder, but also provided a background against which the aircraft were clearly silhouetted to the German night fighters above them. Another problem was the variation in the delay fuses of the flares. This was solved by the fitting of a barometric fuse, but it was some considerable time before hooded flares became available in any quantity. Accurate marking of the aiming point presented a further difficulty. As adequate marker bombs were still under development, ground marking was done with 30-pound and 250-pound incendiaries dropped in salvos. These proved unsatisfactory since they were not easy to distinguish, particularly in the later stages of a raid. By then they had either burnt out or been put out or else had become submerged in the fires and smoke. Various experiments were tried, including the use of coloured flares and a few 4000-pound incendiaries, known as ‘pink pansies’, to mark the release point or the extremities of the target. The latter, while very distinctive when bursting, failed to leave any permanent mark and were also soon copied by the Germans in open country. The flares had the disadvantage of being subject to wind drift.

Flying in the van of the main force, the pathfinder crews also bore the brunt of the enemy counter-attack. Often as they approached the target, their machines were caught in searchlight concentrations and then subjected to intense anti-aircraft fire or attack by enemy fighters. Many were shot down. Before the end of 1942 twenty-one, or nearly half the New Zealanders flying with the pathfinder squadrons, had been posted missing, only two of them surviving as prisoners of war. There were many eventful flights. On one raid to Turin the weather was so bad that only two pathfinder aircraft out of the eight detailed from one base reached their objective. In the vicinity of the Alps the cloud bank was over 20,000 feet, and the two Stirlings flew through it on dead reckoning to come out almost directly over Turin. Only the machine piloted by Flight Lieutenant Barron completed its mission, the other being shot down over the target. During a subsequent attack on Munich Barron’s Stirling was twice attacked by night fighters. The rear gunner succeeded in driving off and possibly destroying one of them but the other, a Junkers 88, made repeated attacks, raking the bomber with machine-gun fire. Parts of the wings and tail plane were torn away and the fuel supply so damaged that both port motors threatened to stop through lack of petrol. Eventually the page 280 flight engineer improvised repairs that enabled the Stirling to limp home. Shortly afterwards, in a raid on Hamburg, Barron had one of the engines shot from his aircraft whilst over the target. Then, during the return flight, the plane ran into a storm and ice began to form on the wings and fuselage. With only three engines it was impossible to get above the cloud, and the Stirling was gradually forced lower and lower until, over Rotterdam, it was flying at barely 2000 feet. The crew furiously jettisoned guns, ammunition, and everything removable in the aircraft. Finally, just as they were preparing to bale out, the ice began to melt and Barron was able to gain sufficient height to cross the Channel safely. Barron had begun flying with Bomber Command in 1941, completing his first tour of operations with No. 15 Squadron. On the formation of the Pathfinder Force, he volunteered and was accepted to fly with No. 7 Stirling Squadron. He soon proved himself ‘an outstanding pilot, showing courage and skill of a high order’. In May 1944, by which time he had completed 77 raids and risen from Flight Sergeant to Wing Commander in 23 months, he was awarded a bar to the DSO. He lost his life in the same month during a raid on the railway marshalling yards at Le Mans.

* * * * *

During the last months of 1942 many of the targets attacked by Bomber Command were in northern Italy. The main purpose of this renewed assault on Italy was to contain the enemy air force in that country and divert attention from the Allied landings in North Africa. There was also the possibility that the heavy bombardment, together with the Allied successes in North Africa, would have serious effects on the morale of the Italian people. Italy might then be driven out of the war or at least rendered more of a liability than an asset to the Germans. Beginning with a raid against Genoa by 112 bombers on the night of 22 October, twelve major attacks were launched during the next two months, the main weight falling upon the port of Genoa and the industrial cities of Milan and Turin. Most of these attacks achieved considerable success. In Genoa the port area and industrial buildings suffered severely, while in Milan there was a very definite wave of panic after the first raid, many of its inhabitants fleeing from the city. The centre of Turin was also heavily hit, railway facilities and industrial buildings, including the Fiat Works, suffering severe damage.¹

This concentrated bombing was made possible by the excellent visibility over Italian cities; with their relatively lighter defences, crews were able to go down low and more readily locate the aiming points. During one raid on Genoa Flight Sergeant Gatland¹ startled his crew by ‘flying between the cathedral tower and the top of a high building’. His machine was hit by fire from the ground but he managed to get it clear of the area and return safely. Losses during these raids on Italy were comparatively light, although there were occasional interceptions by night fighters. When nearing the French coast after the raid against Turin on 28 November, the Halifax captained by Flight Lieutenant Harrison² was repeatedly attacked by a Messerschmitt and badly shot up before the enemy machine was finally driven down by the tail gunner. Like many pilots, Harrison had already experienced other eventful sorties. In the previous March, returning in bad weather from a mission over Germany, his machine crashed in the Yorkshire moors and his navigator was killed. Although suffering from head injuries, a broken arm and a crushed foot, Harrison had dragged his unconscious wireless operator from the burning aircraft before collapsing himself. After five months in hospital he returned to flying and subsequently became a flight commander in his squadron.

While Italy bore the brunt of the Royal Air Force bombing offensive in November and December 1942, several heavy attacks also fell on targets in Germany. Hamburg, Mannheim, Munich, Stuttgart, and Duisberg were each raided by forces of upwards of 200 bombers. In the raid on Stuttgart Flying Officer Brookbanks¹ flew his Halifax to the target with branches of a tree embedded in the engine radiators. ‘Just after crossing the French coast we had come down low to avoid searchlights, had no time to climb clear of some trees and just brushed over the tops with the branches scraping horribly against the aircraft. The propellers were not seriously damaged so we went on.’ The Halifax was damaged in an encounter with night fighters during the return flight and reached base with the branches still in the radiators. Another Halifax captain, Flying Officer Silcock,² detailed to attack the Dornier factory at Wismar, flew through the tops of the flames rising from burning buildings, and the inside of his machine was filled with smoke and pieces of burnt ash. In spite of balloons and anti-aircraft fire at point-blank range, he had gone down to make certain of hitting his target.

Apart from the flares, a fierce fire was soon burning in the waist of the aircraft (runs the official report). Wallace and the flight engineer immediately attempted to subdue the flames. Directly below them lay the bomb bay full of incendiaries, flares and high explosive bombs. Several times the intense heat and fumes forced them back. Then the flight engineer collapsed but Wallace, despite his wounds, returned to attack the flames and eventually, after jettisoning all removable burning material, got the fire out.

Meanwhile the aircraft had been riddled with bullets before the German fighter finally broke away. The mid-upper gunner was wounded and burnt about the face and hands. He was given first aid along with the bomb aimer, and the Lancaster turned for home.

Weather conditions over England were most adverse, with low cloud and rain and Flight Sergeant Wallace contributed considerably to the safe return of the crew (the report continues). When the fire had been extinguished he returned to his wireless set and despite wounds and burns, worked continuously in sending messages and obtaining fixes of the aircraft’s position. His conduct throughout the emergency was extremely gallant.

This incident occurred on Wallace’s sixteenth operational flight with his pathfinder squadron.

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During the second half of 1942 Wellingtons from the New Zealand Squadron flew in almost all the major raids made by Bomber Command, a total of 525 sorties being despatched on 68 missions, when 560 tons of bombs were dropped on Germany and Italy and a total of 160 mines laid in enemy waters. The unit was to suffer severe casualties during this period, 34 Wellingtons being lost. Towards the end of July Wing Commander Olson, who had proved both a popular and efficient leader, relinquished command of No. 75 Squadron to take charge of the bomber station at Oaking- ton. Olson was later awarded the DSO in recognition of his fine work with the New Zealand unit and in raising the operational standard of his bomber base to a very high level. Wing Commander Mitchell,¹ a Scot with a distinguished record in Bomber Command, was welcomed as Olson’s successor. He quickly established himself with the New Zealanders, and under his leadership the unit was to maintain its high reputation for operational efficiency.

German ports and cities were the main targets for the Wellingtons in July, when Duisberg was bombed on four occasions and Hamburg twice. Both cities were well defended, and from the second raid on Hamburg six of the 17 Wellingtons despatched failed to return. Their captains were Flight Lieutenant Wilson¹ and Flight Sergeants Croall,² Gilbertson,³ Hutt,⁴ Johns⁵ and Sutherland.⁶ Members of Croall’s crew were fortunate to survive when the controls failed just as the bomber was crossing the German coast on the return flight. After being badly shot up by anti-aircraft fire over Hamburg, the Wellington was flying low when, in the words of the captain:

The control column came back loosely into my body and a few seconds later we hit the sea. Water came rushing in … everything went dark …. I felt the seat crushing me against the instrument panel. Struggled free and on reaching the surface found all the others except the rear gunner. The wing dinghy was inflated so we scrambled in. Most of us were bruised and cut, some more than others but by paddling, drifting and swimming alongside we at last reached the shore at daylight and were captured shortly afterwards.

For Bomber Command’s heavy attack against Dusseldorf on 31 July, No. 75 Squadron sent eleven Wellingtons. Crews reported a successful raid, large fires being seen near the aiming point. Searchlights and anti-aircraft fire were particularly active, but few night fighters were sighted during the flight over Germany and all the squadron’s bombers returned safely. During the next few weeks there followed attacks on Essen, Frankfurt, Mainz, Osnabruck and Duisberg. Mines were also laid in the entrance to the U-boat base at St. Nazaire and in the shipping lanes off the Frisian Islands. In these operations four Wellingtons were lost, three of them captained by New Zealanders—Flying Officer Dobbin,⁷ Pilot Officer Bradey,⁸ and Flight Sergeant Barclay.⁹

Towards the end of August the squadron left Feltwell, where it had been based since its formation, for RAF Station, Mildenhall, a large bomber station near Bury St. Edmunds, in Suffolk. The move was not allowed to interfere with operations, and in the last week of the month twelve and ten Wellingtons were despatched to take part in the pathfinder raids against Kassel and Nuremberg. On both occasions many fires were seen and the success of the attacks was confirmed by subsequent daylight reconnaissance. But the enemy defences were active and several crews from the New Zealand Squadron were among those who reported encounters with night fighters. In the raid on Kassel one Wellington was fiercely attacked when approaching the city. Although the rear gunner eventually drove off the fighter, the bomber was badly shot up and crash-landed on reaching England. The following night two Wellingtons were lost, while a third, with its petrol tanks holed and controls damaged, was just able to reach an airfield in southern England.

Objectives for the squadron’s bombers in September included the ports of Bremen and Emden and the industrial centres of Dusseldorf, Essen and Frankfurt. In addition, minelaying sorties were flown on six nights to areas off the Dutch coast, the entrances to St. Nazaire, and the U-boat training grounds in the Baltic. While substantial damage was inflicted in several of these raids, the outstanding success was the attack against Dusseldorf on the night of the 10th when a force of 476 aircraft was despatched by Bomber Command. Although there was some ground haze in the target area, the pathfinders succeeded in marking the aiming point accurately and a concentrated attack developed. Wellingtons from No. 75 Squadron flew in the last stage of the raid and on arrival found large fires burning in the city. Searchlights and anti-aircraft batteries were active, but the crews were able to drop their incendiaries and high explosives in the centre of the conflagration. Later reconnaissance revealed heavy damage in the centre of the city, more than one hundred acres between the Rhine and the main railway station being devastated.

The long association of the New Zealand Squadron with Wellington aircraft, which had lasted since formation, came to an end in October. On the 15th B Flight moved to the Conversion Unit at Oakington for instruction and training on the four-engined Stirlings which were to replace the Wellingtons. Operations were meanwhile continued by A Flight, whose crews followed a fortnight later. Most of the aircrew had developed a strong affection for their ‘old Wimpeys’ and they regretted the change.

During the first fortnight of October the Wellingtons had flown in raids on Krefeld, Aachen, Osnabruck and Kiel, a total of 56 sorties. In the attacks on Krefeld and Aachen there was considerable haze in the target area and the bombing was scattered. Cloud and haze prevented some aircraft from reaching Osnabruck but all the New Zealand crews were able to bomb and start fires. The attack on Kiel was made in clear weather; crews found the aiming point with less difficulty than usual and reported particularly large fires in the dock area. Targets attacked by Wellingtons from A Flight during the latter part of the month included Cologne, Essen, Genoa and Milan. The flights to Italy were made under difficult weather conditions. On 24 October, when Wing Commander Mitchell led five Wellingtons to Milan, two of them, captained by Sergeants Hugill¹ and McConnell,² failed to return. The squadron’s last sorties with Wellingtons were flown the following night when mines were laid off Brest and near the Frisian Islands.

The change to Stirlings was accompanied by a further move to RAF Station, Newmarket, the site of the famous racecourse in Cambridgeshire. Thus to suspicion of the new after the old and tried weapon was added the difficulty of operating from a new airfield in unfamiliar surroundings.

‘The early days at Newmarket were rather trying,’ writes one of the senior officers. ‘In addition to the normal feelings of uncertainty before crews became accustomed to the new type of aircraft, there was the strange airfield. The bank a short distance from the end of the main runway did not help matters. It was a prehistoric fortification known as the Devil’s Dyke and is reputed to have been constructed by Queen Boadicea. Taking off in daylight over the Devil’s Dyke caused no feelings of apprehension, but at night, when it could not be seen, was another story. However, on the occasions when he operated, the squadron commander made a point of taking off first over the Dyke, and although one machine crashed on the bank and others had narrow escapes, the bogey was eventually laid.’

Meanwhile, however, the difficulties of operating with the new aircraft in the northern winter and further casualties, which included the loss of their commanding officer, were to make this a rather unhappy period for No. 75 Squadron.

The first operational sorties with the Stirlings were flown on the night of 20 November, when four crews from B Flight took part in a raid on Turin, the New Zealand captains being Flying Officer

BATTLE OF THE ATLANTIC

¹ Sergeant H. J. Hugill; born Auckland, 26 Jan 1921; fruit grower; joined RNZAF Jul 1941; killed on air operations, 25 Oct 1942.

² Sergeant J. A. McConnell; born Dunedin, 16 Nov 1920; grocer; joined RNZAF Aug 1941; killed on air operations, 25 Oct 1942.

page 289 Trott,¹ Flight Sergeant Bailey² and Sergeant Franklin.³ The following night two Stirlings were among the force which attacked Stuttgart, and a further six sorties were flown to Italy before the end of the month. Meanwhile A Flight had been held back at Oakington by bad weather which prolonged their conversion period. A further misfortune was the loss of Sergeant Broady⁴ and his crew, who were killed when their aircraft crashed during a training flight. However, the second week of December found the squadron once again at full strength but, much to the disgust of the air- crews, unfavourable weather and difficulties with the new machines severely hampered operations for the remainder of the year. The frequent mechanical failures were a source of constant disappointment and frustration to the ground crews, who did their utmost to maintain a high standard of serviceability. Nevertheless, defects frequently developed as the bombers were about to take off or shortly after they had become airborne and missions had to be aban- doned. During the raids on Italy several crews were forced by engine failure to turn back during the climb over the Alps. Of the 37 sorties detailed during December only 17 were completed successfully. The squadron was particularly unfortunate on the 17th when, of the five Stirlings which took off to attack the Opel Works at Fallersleban, four failed to return. Wing Commander Mitchell was among the missing crews, which included ten New Zealanders, one of whom, Flying Officer Jacobson,⁵ was a captain. Pilot Officer McCullough,⁶ who flew the only Stirling to return, reported that his machine had been attacked twice by enemy fighters in the vicinity of the target. In this bleak period the one bright spot was the raid against Turin on the night of 9 December, when all five Stirlings reached the target and returned without incident, crews reporting many fires and huge columns of smoke after the bombing. But a few nights later when four Stirlings were about to take off to lay mines off Bordeaux, a strong cross wind caused the first three bombers to swing violently before they became airborne. The fourth struck the top of the Devil’s Dyke, straightened up for a moment, and then crashed a mile from the airfield. The mines exploded and the entire crew were killed.

The New Zealand Squadron was not alone in its misfortunes during this period. Other units were experiencing similar difficulties and suffering casualties in their early operations with the new heavy bombers. Nevertheless, in spite of the various setbacks and disappointments, the year had seen marked developments in the operations of Royal Air Force Bomber Command. Although no great numerical expansion had taken place, the force had changed from one primarily equipped with medium bombers to one essentially heavy in character. The Lancaster was now replacing the Wellington as the mainstay of the offensive. In tactics and technical equipment it had been, in many ways, a period of experiment, the results of which were to be seen in later operations. Air Marshal Harris himself regarded it as ‘a year of preparation in which very little material damage had been done to the enemy which he could not repair from his resources, but in which we had obtained or had in near prospect what was required to strike him to the ground, and learned how to use it.’