The next day, Tuesday, 27 July, it was the Americans’ turn for a rest. Officially, they cited uncertainty over the weather as the reason for taking the day off, but the battered and harassed crews were in desperate need of a little respite. While they recuperated, Butch Harris was eager to resume his battle on Hamburg. Whatever the Americans might have said about the weather, as far as he was concerned the forecast for that night looked promising. A Mosquito reconnaissance plane was sent out over Hamburg later that morning to confirm conditions: its pilot reported back that, other than a light smoke haze from the fires that were still burning, the skies were perfectly clear. So, without further hesitation, Harris ordered his second maximum effort on Hamburg to go ahead.

The plan for tonight was similar to the one used on the night of 24 July. ⁴Once again the bombers would be using Window, and flying in a tight stream through the German defences. Zero Hour was again 1.00 a.m. and the aiming point was exactly the same as last time. The only real differences from the previous plan of attack were a slight change to the route and an alteration to the type of bombs they would be using.

Tonight, instead of flying to Hamburg from the north-west, the bomber stream would take a route right across the Schleswig peninsula, then come back to approach Hamburg from the northeast. The idea was to make it look as if they were attacking Kiel or Lübeck – indeed, some historians have stated, wrongly, that the bomber stream passed directly over Lübeck as part of the ruse. ⁵Whatever the case, it was an ineffective feint: everyone in Hamburg was expecting another attack, and the defences were still on high alert. However, it did mean that the run-in to the aiming point would be coming from a different direction, so any creepback in the bombing would land on a new part of the city. In the next few weeks the people of Hamburg would come to believe that the RAF had bombed the city with a methodical precision – ending their carpet of bombing at a particular street one night, and starting again with the next street along on the following night. Of course such accuracy was impossible, but there was an element of truth in the rumour. By coming at the city from different directions, the bombers could ensure that every suburb was hit during the series

of raids. Over the course of their four raids on the city the RAF attacked in turn from the north-west, the north-east, the north and the south. Effectively they were destroying the city a segment at a time.

The other main change to the plan was just as significant. Tonight the planes would be carrying far more incendiary bombs than they had on the previous attack – 240 tons more. ⁶Some historians have claimed that this change was made for purely operational reasons: the aircraft had further to fly, so the Halifaxes and Stirlings had reduced the weight of their loads by replacing their high-explosive bombs with lighter incendiaries. ⁷But that is not the whole story. Bomber Command planners were constantly revising the proportions of bomb loads, and it was becoming increasingly obvious that incendiaries did far more damage than explosives. Hamburg was not considered a particularly flammable city – most of the old wooden buildings in the city centre had already been burned down in the great fire of 1842 and replaced with more modern brick and stone buildings – but when the operation’s planners saw how well the city had burned on the previous attack it seemed worthwhile to increase the proportion of incendiaries. The Lancasters had already been ordered to carry ‘maximum economic incendiary loads’ when the Hamburg raids were first conceived. ⁸Tonight this order was extended to the Stirlings and Halifaxes.

As evening approached, morale was riding high at all levels of the RAF. Harris and his staff believed that they were at the start of a new era in the bombing war: now that German defences had been blinded by Window, Bomber Command effectively had command of the air, and Harris was convinced, more than ever before, that it would be only a matter of time before Germany was forced to surrender. The airmen were similarly enamoured of their new radar-jamming device. The casualty rate had plummeted since they had started using it, and the draughty job of shoving bundles of silver strips through the flare chute had become a labour of love. A new spirit of optimism was spreading through airfields up and down the country. During their briefing for that night’s operation the crews were read a message from Harris congratulating them on the success of their previous attacks on Hamburg and Essen. It was greeted with great enthusiasm by the men, who were at last beginning to feel that they were making a difference. Perhaps their commander-in-chief had been right all along – perhaps they wouldbe able to win the war by bombing alone.

Confidence was so high that officers of increasingly senior ranks decided to join the crews on their trip that night. Station commanders were not normally allowed to go out on more than one operation each month, but that evening no fewer than five decided that it was time to see the effects of Window for themselves. ⁹Two air commodores also decided to fly – Air Commodore W. A. Brooke of 4 Group, and Air Commodore A. M. Wray of 1 Group. However, the highest-ranking officer to accompany the bomber crews was an American. Brigadier-General Fred Anderson, in charge of the Eighth Air Force’s bombers, was so eager to learn how his allies operated that he joined a Pathfinder crew. He had been extremely impressed on the previous raid to Essen, but flying as second pilot to Flight Lieutenant Garvey in a Lancaster from 83 Squadron, he would witness destruction on a scale few people had ever believed possible. ¹⁰

* * *

It had been a glorious summer’s day, and when the bombers took off at around ten o’clock the dying sun had painted the sky blood-red. All along the eastern edge of England the air was soon filled with the drone of 787 aeroplanes heading off across the North Sea. To most of those who lived along the coast it was a comforting sound. At this stage of the war, bomber crews were still treated as celebrities by newspapers and newsreels, and as heroes by the general population: apart from the army in North Africa and Sicily, they were the only force capable of taking the war to Germany. People who lived near airfields would often come out to watch them take off, particularly on a fine, warm night. Children always waved, blissfully unaware of the realities of warfare.

Apart from a few minor mishaps, the whole bomber force took off safely. A small proportion turned back because of mechanical problems (only forty-two aircraft), but the vast majority congregated into three streams and made for their rendezvous point eighty miles off the German coast. ¹¹As on the previous raid, they began Windowing a few minutes later. Also as on the previous raid, the Pathfinders dropped yellow markers as they crossed the coast in order to concentrate the stream of planes more tightly. (A second set of route markers would be dropped later, further to concentrate it.)

The route markers were all that the defending Luftwaffe fighters had to guide them to the bomber stream, once their radar systems had been blinded by Window. A Pathfinder in the vanguard of the stream had been shot down before Window had taken effect, but now that the German pilots’ radar screens had fuzzed over there was little they could do but head for the lights in the hope that they might stumble across some British bombers in the dark.

They were rewarded with just a single victory over a Lancaster from 467 Squadron. In return, one of their own Ju88s was shot down over Heide. In total, only five British bombers were lost on their way to the target, at a cost of two German night fighters. So far, Window had proved every bit as effective as it had been on the first raid, three nights before.