The Invasion Has Started!

by William Levenor

Bombed day and night, the enemy faces an increasing tempo of aerial assault as the Allied air forces form huge reserves of air power.

The continent of Europe is the target for today — and for every day and every night until Germany collapses. Is it the prelude to invasion? No, it is the invasion itself. True, no occupying force of Allied troops has yet seized continental territory from the Axis; but make no mistake about it — the invasion has started.

In the bombardment of the Axis citadel of Europe, the pace has been set by the fantastically destructive raids of the past winter and early spring. Now, the Royal Air Force and the US Army Air Forces are hitting their stride and there will be no lessening of the punishment they mete out to Germany and the lands occupied by the Nazis.

To draw a comparison that is valid, for all its unpopularity among air enthusiasts, the present intensive bombing attacks on Europe have much the same relationship to the coming occupation by Allied forces as the artillery barrage to the advance of infantry in a ground action. The "softening up" barrage and the infantry advance, together form the "attack." So it is with the invasion of Europe — remorseless aerial bombardment is intended to soften up (and beyond question is softening up) the Axis-held continent in preparation for the final combined operation which will actually occupy territory.

That is not to say that the aerial bombardment is as narrowly restricted, either in range or immediate objective, as an ordinary artillery barrage — however stupendous the latter may be. It is a much more extensive operation and does what field artillery has been unable to do effectively — it strikes at the very vitals of the enemy far behind the "front" lines, smashing his industries, wrecking his transportation, ruining his communications and, if not shattering the home morale, certainly in the long run building up such an accumulation of discomfort, fatigue and distress that the results are an inevitable drag on his war potential.

What is the pattern of the bombardment? Large-scale area bombing by the RAF in night operations; heavy daylight precision attacks by increasingly large forces of US Flying Fortresses and Liberators, both accompanied by lighter attacks carried out on separate objectives by smaller bombers. It is a round-the-clock business as often as the weather permits — and the weather will permit it more frequently through the late spring and the summer.

It is not as rigid as that may sound. The RAF bombs by day and the AAF will handle their share of night operations. But in general, each is doing the job it is best equipped and trained to do. Complete understanding exists between the two forces, and operational cooperation is in the offing — may, in fact, have become an actuality by the time this is printed.

Plans for this operational cooperation— closely coordinated day-and-night attacks, for instance, on the same target— already have been made. Maj Gen Ira C Eaker, commanding the US 8th Air Force, said in March that as soon as weather conditions remained favorable for 24 hours, the Fortresses and Liberators would go out by day to light up a fat target for that night's RAF operations. Or, the Americans will go out for a precision cleanup job by day on a target the RAF has softened up the night before.

This cooperation, wherever and however discussed, inevitably brings to the fore the AAF's established method of daylight, precision bombing of specific objectives, which has been freely criticized by many writers who favor the massive "area bombing" technique in night operations. It has been said repeatedly that the American method, developed for defense of Caribbean and Pacific outposts. is not suitable for western Europe.

In general, these criticisms can be reduced to three generalizations:

  1. — In daylight operations, losses from enemy fighter attacks become prohibitively high beyond the range of fighter escorts;
  2. — on long flights into the interior Germany, the bomb loads of the Liberator and Fortress are too small to justify the operations
    [The Boeing company recently released an approved statement to the effect that the payload (which undoubtedly consists largely of bombs) of the latest Flying Fortresses — not the newer, heavier bombers coming up — has been boosted to 10 tons. Assuming 4,000 pounds for crew, guns, fuel, etc, that would bring the Fortresses' bomb load well up to that of the touted Avro Lancaster of the RAF. An important point to be remembered in that connection is that the Fortress carries 13 .50-caliber machine guns, while the Lancaster carries only 10 .30-caliber guns — a tremendous difference in firepower.— Ed];
  3. — precision, high-altitude bombing is practicable only in fine weather, which most of the time does not exist over western Europe.

General Eaker has answered the first two emphatically and categorically: American bomber losses on daylight raids are proportionately no higher than RAF losses on night raids; hundreds of newer and bigger American bombers will soon be operating. On the weather factor, the answer is not so flat. Fog and mist obscure the target frequently, but successful daylight raids have been carried out despite this obstacle.

As an instance of this, it is necessary only to recall the first raid by American heavy bombers on Germany proper — the attack by both Fortresses and Liberators on Wilhelmshaven and Emden last January 27. Despite poor visibility, later reconnaissance photographs disclosed the operation was highly successful. Furthermore, the unescorted heavy bombers encountered "swarms" of enemy fighters, shot down a large number of them, but lost only three of their own number.

General Eaker is the authority for the assertion that high-altitude precision bombing of targets in Germany and Nazi-occupied Europe, with an economically low rate of losses, has been proved definitely feasible. The rate of losses, in fact, has been extraordinarily low. The RAF figures that its night bombings are profitable if the rate of loss is no more than five per cent. The natural thing to expect — and critics of the AAF daylight operations have prophesied it — is that losses in daylight operations would be higher. There is reason to believe, however, that the 8th Air Force's losses so far this year have been under three per cent, which would be phenomenally low.

No, despite such persuasive bystanders as Allan Michie, the necessary requirement is not abandonment of daylight raids on Germany, but stepping up the scope of both day and night attacks, hitting more targets, blasting them more heavily, coming back to them more frequently. It is to hit so hard, and in so many scattered places at the same time, that the Luftwaffe, already declining in strength, will be unable to cope with the air armadas that are pounding Europe. It is to keep the bombardment going day and night, without respite, forcing Germany to man her defenses constantly, instead of at night only.

That, in fact, is just what is in store for the enemy — a ceaseless, relentless pounding, by all types, at all hours. The experimental stage is over, says General Eaker, and the next step is to build up the strength of both AAF and RAF — but particularly to swell the numbers of American bombers until the 8th Air Force is operating on a full partnership basis with the RAF.

The new and bigger planes to make this possible are on the way, he reports, carrying three to four times the bomb loads of the Fortresses and Liberators. And by summer, hundreds of American bombers will be operating from Britain, cooperating closely with the RAF, and able to choose targets at will throughout Germany or western Europe. The day and night offensive will be so mighty that "we won't give a damn whether the Germans know we are coming or not."

Admitting that when the Fortresses raided the freight yard at Rouen last August the planes designed for hemispheric defense were coming up against the kind of "big league" opposition they were not intended specifically to meet, General Eaker said many experts — American as well as British — confidently expected them to fail. But they didn't, and he asserted the British themselves now were convinced of the soundness and practicability of daylight, high-altitude operations over western Europe.

This was borne out by the RAF itself in April, in a review of studies of reconnaissance photographs. The consensus at RAF headquarters was that American heavy bombers, in their daylight attack March 18 at Vegesack, had struck what may have been the heaviest blow of the war against German U-boat operations.

The bombers inflicted heavy damage on seven of the 15 U-boat pens, and submarine experts expressed belief the production of the yard would be impaired for several months. The RAF praised the AAF raids on the Hamm railway junction, on Rennes — where a naval stores station was badly damaged — and on Wilhelmshaven, where nearly all the harbor fixtures were damaged.

Of the April 4 raid on the Renault works at Billancourt outside Paris, the RAF reported that although full reconnaissance studies had not been completed, the attack was without doubt extremely successful, with hardly a single building in the entire plant area escaping damage.

So much for the practicability of daylight bombing over Europe. It is practical, all right — pays big dividends. And all critics to the contrary, the American heavy bombers have the speed and the firepower to defend themselves and carry out their mission, even in the face of heavy fighter opposition. That has been demonstrated so amply that the point is no longer worth belaboring. It's still thrown into the argument by night- minded critics of the American heavy bombers, but their assertions of inadequate firepower, armor and speed don't stand up under scrutiny.

The bomb-load criticism is more valid. Designed for long-range defense, the Fortress and Liberator carried normally 6,000 to 10,000 pounds of bombs, as against about 16,000 pounds in the large British bombers. But the bigger planes are on the way, and so are more Fortresses and Liberators with greatly increased bomb loads. Other lessons have been learned, too, such as the need for greater armor protection against low-velocity explosive shells, and the necessary changes have been adopted.

This extensive discussion of American types and their success might indicate a belief that the AAF had all the answers, and would throw all the weight. It should be obvious, however, that there is no such implication. There is only the explanation that, in Europe, the American heavy bombers are doing — and doing quite well — a job that is bigger than the one for which they were designed. In cooperation with the RAF, American airmen will carry their full share of the load, although so far the RAF manifestly is way ahead of them in tons of bombs dropped and damage inflicted. The cooperation is a fact, and the pattern set. The job has started.

But it's a long way from finished. General Eaker speaks of "hundreds" of American bombers by summer, of AAF strength in Britain equaling RAF strength. But as yet the largest number of American heavy bombers to be announced as participating in a single raid was 133, in the assault on the Renault plant. If the RAF is unable to repeat frequently its 1,000-plane raids, at least part of the difficulty may be disagreement with the Admiralty as to the most profitable occupation for heavy bombers.

The 1,000-plane raids were accomplished only by "borrowing" some of the planes normally engaged in operations at sea, patrolling the vital approaches to Britain, seeking the U-boats lying in wait for convoys. The Admiralty quite obviously regards this as an essential operation, and rightly so. The RAF thinks it is productive of greater results to hammer the U-boat bases. It's a difference of opinion not likely to be resolved.

To carry on 1,000-plane raids every night, if the maximum "profitable" operational loss is used — five per cent — would require a replacement rate of 1,500 planes monthly. Assume that there was a further net reduction of 600 planes (a conservative figure) by reason of landing and take-off accidents, damage from antiaircraft, and other reasons. That means replacements at the rate of better than 2,000 planes a month would be required for nightly 1,000-plane raids by the RAF alone. Even for raids of that size three nights a week, the replacement-and-repair rate would run around 1,000 a month. And to start such operations, a force of at least 3,000 planes— preferably 4,000 — would be required.

Then add to this the AAF participation in round-the-clock operations. Assume, for instance, that attacking specific targets instead of area targets, a comparable amount of effective destruction can be inflicted on enemy installations with one-third the total plane strength (disregarding, for the sake of the point, the question of bomb load). That would mean 300 planes a day operating over Europe. An initial strength of 1,000 is indicated, and replacement-and-repair, figured on the same basis as for the RAF above, would be about 600 a month. For three-days-a-week operations on this scale, assume replacements would total 150 bombers a month.

What does it add up to? Initial combined strength of 5,000 heavy bombers, with replacement-and-repair totaling 2,600 a month. Nor is plane production the only factor to be considered. Every bomber lost means a crew lost, too, and at 2,000 heavy bombers a month that would mean replacement of some 18,000 trained crewmen — pilots, navigators, bombardiers, radiomen, gunners. Will the training facilities of the two countries provide air crews in any such numbers as that?

Furthermore, the beginning of operations on such a scale would require the accumulation of huge amounts of aviation fuel. Britain produces none — every gallon of gasoline has to be imported and that imposes a tremendous load on an already heavily overtaxed merchant marine. The U-boat menace will have to be diminished before US and British airmen can feel completely safe on that score.

That is, of course, much too gloomy a picture. Few of the operations over the continent have exacted the five per cent toll. As the size and frequency of combined RAF-AAF attacks increase, the toll can be expected to drop. Already, the Nazi defenses have their hands more than full; it is highly unlikely, with their strength declining as it is, that they can inflict maximum penalty on the growing attacking forces.

Nor is it necessary to assume that continuous operations of such huge size will be necessary to soften up the continent to the point at which an airborne and amphibian landing of Allied ground forces would usher in the final stage of the war in Europe. But a tremendous backlog of strength is required for any continual, large-scale attack.

Continuous, round-the-clock bombardment of Europe on such a stupendous scale may come eventually. Certain it is that the scale of operations is growing now and will continue to grow. Bad weather may ground the heavy bombers occasionally, but not with sufficient frequency to give the Nazis much comfort or respite.

The culmination of this aerial blasting, the landing of Allied troops on the soil of Nazi-occupied Europe, has been promised this year. The campaign is underway, as every day's headlines demonstrate. The invasion has started.

This article was originally published in the June, 1943, issue of Flying magazine, vol 32, no 6, pp 21-23, 158, 160.
The PDF of this article [ PDF, 11 MiB ] includes photos of airborne Lancaster and B-17s, photos of bomb strikes, and a ground shot of the nose of a B-24.
Photos credited to British Information Service, US Army, British Combine, Central Press, Acme.