To get a second opinion, Roosevelt sent another Irish-American to Britain. 'Wild Bill' Donovan was ostensibly in England to study the extent of German espionage and the nature of British counter-measures. In fact, he was to report to Roosevelt Britain's chances of survival. Sending a man on an intelligence mission that was really a cover for a diplomatic function was a curious reversal of the usual way of doing such things.

A few days later, the storm clouds again gave way to clear blue sky. At about 2 p.m., when most of England was sitting down to the ritual of Sunday lunch, something happened that was so unusual in the air war that this might have been unique: two ace pilots clashed in combat.

The South African 'Sailor' Malan ended the war as one of the top-scoring aces on the Allied side. He was important, too, for the influence he had upon RAF tactics an formations.

Born in Wellington, South Africa, Adolphus Malan was a man of burly build with an amiable smile that made the men who met him unready for the deep and clinical hatred that he had for his German opponents. He told one of his fellow officers that to badly damage enemy bombers so that they arrived home with dead and dying aboard was better than shooting them down: it had more effect on Luftwaffe morale. So that is what he tried to do.

Malan had been a merchant navy officer before volunteering for the RAF in 1935. He proved to be an exceptional pilot, according to his flying instructors. He was a flight commander by the time he saw action in May 1940. On the receiving end of his bullets this day was an even more revered master of the fighter pilot's trade: the legendary Molders. Both men have been mentioned by their peers as possibly the greatest fighter pilots of the war. Werner Molders was a handsome young man whose drawn face, deepset eyes, bony nose, and thin mouth were seldom captured on film in the act of smiling. He was an introverted man, and this serious demeanour earned him the nickname 'Vati' ('Daddy'). So determined was he to be a fighter pilot that (like many others before and since) he endured the agonies and humiliation of constant air sickness.

Molders took over Galland's command in Spain just as the new Bf 109 fighters replaced the old biplanes. This changed the odds and he returned to Germany with fourteen destroyed enemy aircraft in his log book. He was a skilled administrator and a dedicated teacher, as well as Germany's top fighter ace. Many Nazis took exception to the way that 'Vati' Molders made no secret of his Catholic religion, but Göring made quite sure that no harm came to him on that account. In 1940 it was decided that the coveted Knight's Cross of the Iron Cross would be given to a pilot who shot down twenty enemy planes. Molders was the first fighter pilot to get it. He was to become the Luftwaffe's General of Fighters before his twenty-ninth birthday.

Sunday 28 July was an auspicious day for Molders. This was his first day as Kommodore of the entire JG 51. (The previous day 'Onkel Theo' Osterkamp had gone to become Jafь 2, the commander of all the fighter planes in Air Fleet 2.) Concerned as he might be by his seven weeks out of action, and the victories of Galland and Hauptmann Helmut Wick (the other two top German aces), Werner Molders could this day reflect with satisfaction that he was the youngest Kommodore in the Luftwaffe.

With Molders there were four Staffeln of Messerschmitts, and in keeping with Fighter Command policy Spitfires were sent against them, while Hurricanes were vectored on to the German bomber formation. 'Sailor' Malan was leading twelve Spitfires of 74 Squadron from Manston. As they closed, Malan chose a victim in the leading flight, fired, and watched him go down. Molders was leading that formation; he turned and shot down a Spitfire. For Molders this was his 129th combat mission of the war and his twenty-sixth victory (not including the fourteen aircraft shot down in Spain). He came round again, looking for his twenty-seventh.

Both Molders and Malan were fast, but Molders was split-seconds faster. Even as Malan was scoring his victory, Molders was already on his tail. Malan turned in toward the attack — the classic reaction of the fighter pilot — and kept turning tightly enough to bring Molders into his sights. His machine-gun bullets raked the Messerschmitt. Had the Spitfires been armed with cannon, Molders would not have been able to nurse his badly damaged machine back to his base at Wissant. When he landed, his leg wounds were bad enough to put him into hospital. It was to be another month before Molders could claim victim number twenty-seven.

Enough Messerschmitt pilots failed to make it back across the Channel for German rescue float-planes to be sent out to search for them. These large twin-engine rescue air craft were painted white, with eight large red crosses in evidence. The Air Ministry had decided that any seen near Allied shipping or the English coast should be shot down. This instruction had been passed to all squadrons on 14 July, and in keeping with it, Hurricanes of 11 Squadron shot one down into mid-Channel and did considerable damage to another that was on the water 2 miles west of Boulogne.

The resulting controversy was not confined to the rival propaganda industries. Some RAF pilots vowed that they would not obey such an instruction. Others wanted to see it in writing. Publication of this Air Ministry Order, on 29 July, with its legalistic phrasing and vague talk of confining such attacks upon unarmed aircraft to "areas in which operations are in progress," did nothing to improve matters or even clarify them. For it was only where operations were in progress that drowning aviators would be found.

Molders's badly damaged fighter plane provides an example of another problem. On this day alone, two Junkers Ju 88 bombers of 9/KG 4, the General Wever Geschwader based at Amsterdam-Schipol, were damaged by anti-aircraft gunfire over the Thames Estuary. One did not get back as far as its base. Both crashed on landing and were completely written off. Almost all the survivors were wounded. Another Ju 88 of the Edelweiss Geschwader had engine failure, and forced-landed heavily enough to be severely damaged. Neither was Molders's Bf 109 the only fighter that would not be ready to fly next day, or for many days after that. Official Luftwaffe records show a Bf 109 of 11/JG 27 crash-landed away from its base, with its pilot wounded. It was badly damaged, and two more Bf 109s were written off in crash landings, one of which killed the pilot. Two more fighters of JG 51 were damaged in forced landings that afternoon, and there was the Heinkel float-plane damaged near Boulogne, and a Do 17Z of KG 2 that was written off in an accident that had nothing to do with enemy action.

It was like this almost every day: collisions during taxiing, take-off, or landing, as well as curious entries that show aircraft that simply disappear, as a Ju 88 of II/KG 51, the Edelweiss Geschwader, had done on the night of 25 July. There is no record of its being encountered anywhere, by army, navy, or air forces on either side of the Channel. These marginal losses sometimes account for he arguments that arise about the battles of 1940.

In Britain there was a highly efficient organization that salvaged every scrap of airframe that could be collected. Airframes were melted down, and much of the German alloy took to the air again, as part of RAF machines.

For damaged RAF aircraft there was an amazing record. Of all the fighters struck off squadron strength because they could not be repaired locally, no less than 61 per cent flew again. This was due to the efforts of the Civilian Repair Organization — the CRO.