The long frustrating debate over the timing and location of a Second Front in Northwest Europe came to an end at the Quebec Conference of August 1943. Winston Churchill, Franklin Roosevelt and their senior military advisers were briefed on the progress of Operation Neptune, the planned assault phase of Operation Overlord. They agreed the invasion of France would take place in May 1944. The planners outlined four conditions that had to be met if the landings were to be successful. First, the enemy must remain ignorant of the actual landing area. Second, the Allies must achieve complete air and naval superiority in and over the English Channel. Third, the local defences must be largely destroyed by air and sea bombardment. Finally, the Allied air forces must prevent the enemy from bringing up reinforcements quickly, especially during the first few days after the landings.Accomplishing these four tasks would not be easy. Fortunately, the Germans were convinced the invasion would take place at the mouth of the Somme River or in the Pas de Calais region opposite Dover. The Allied deception plan to draw attention away from Normandy worked well because the Germans wanted to believe the intelligence they had received about possible landings north of the Seine River. Allied planners used intelligence from Ultra to help track the location of all enemy divisions in France. The same planners were certain the enemy had not identified Normandy as the landing area.

The Allied air forces promoted the deception plan while isolating Normandy from the rest of France. On the eve of the June 6, 1944, invasion, the German army reported that “constant air attacks” had destroyed bridges over the Seine and crippled rail transportation with raids on marshalling yards as far north as Brussels, Belgium. The report concluded that the “concentration of air attacks on coastal defences between Dunkirk and Dieppe…confirmed the focal point of a large-scale landing” in that area.

This deception was an extraordinary achievement, but more remarkable was the enemy’s belief that Normandy was a feint and a second landing would soon take place. As late as July 23, on the eve of the destruction of the German forces in Normandy, German army commanders still believed that the “sector from north of the Somme to the Seine is in great danger.” They refused to transfer infantry divisions to the Normandy battlefront.

The greatest challenge for the Allies seemed to be achieving air superiority. On D-Day the English Channel would be full of slow, vulnerable targets. The 4,126 landing ships and landing craft would be accompanied by 864 merchant ships and 736 ancillary vessels. Most of these would sail at the same time to be marshalled through the narrow shipping channels cleared of mines. The 1,213 Allied warships–the largest modern fleet ever assembled–could fight back against air or naval attack, but in the congested waters in front of the invasion beaches they too would be easy targets for the German air force.

By June 1944 the Allied air forces had more than 13,000 operational aircraft–plus 3,500 gliders–in Britain. Close to 11,590 planes were assigned to protecting the invasion. Long-range-fighter patrols covered much of France while continuous screens of low- and high-altitude fighter-bombers shielded the beaches, the Channel and the assembly areas as far back as the Isle of Wight. All told, 3,700 fighters were committed, including the Royal Canadian Air Force wings of 2nd Tactical Air Force.

The air effort on D-Day was more than sufficient. During the winter of 1943-44 and the following spring, the bomber offensive had reduced the Luftwaffe to a shadow of its former self. The American B-17 and B-24 bombers–escorted by Mustang fighters–had destroyed much of Germany’s day-fighter force. British and Canadian crews of Bomber Command had forced the enemy to divert aircraft and other resources to the defence of Germany. In June 1944, the Luftwaffe had fewer than 200 available aircraft in all of France. “If it’s white, it’s American. If it’s black, it’s British. If you can’t see it, it’s the Luftwaffe” is how German soldiers described the situation. The German air force was completely overwhelmed and air superiority was achieved beyond the Allied planners wildest dreams.

Naval superiority was never really in doubt and historians have taken the navy’s role in the invasion more or less for granted. Canadians have just begun to hear about the exploits of the minesweeping flotilla at Omaha beach or the battle fought by the RCN’s tribal-class destroyers Haida and Huron.

Admiral Bertram Ramsay, the overall naval commander, believed that the underwater mine was the “greatest obstacle to success” in the assault. The RCN agreed to contribute 16 bangor minesweepers to Neptune, but their crews had to be trained to use the serrated line or “sweep” to cut mooring cables and bring the mines to the surface for destruction. On D-Day, 10 RCN bangor minesweepers, which formed the 31st Canadian Minesweeping Flotilla under Commander A.H.G. Storrs, led the United States 1st and 29th divisions towards Omaha beach. Our other minesweepers served with the 4th, 14th and 16th flotillas. The ones that were part of the 14th helped open the path to Gold beach.

Haida and Huron were part of the 10th Destroyer Flotilla that was based in Plymouth. They helped form part of a strike force capable of dealing with the landings. Allied air superiority meant the German navy could operate only at night. However, the German destroyer flotilla, which was based in the Bay of Biscay, was a serious threat. It included two destroyers armed with 5.9-inch guns and eight torpedo tubes. They were larger, faster and packed a heavier punch than even the tribals.

The German flotilla was ordered into action on D-Day, but thanks to Ultra the flotilla’s moments were known and Beaufighter aircraft, including those of 404 Squadron RCAF, kept the destroyers bottled up in the harbor at Brest until June 8. Naval historian Michael Whitby says the bold tactics and persistence of Haida and Huron played a key role in destroying the German flotilla.

British planners, still haunted by their memories of Dieppe, insisted on an enormous air and naval bombardment designed to destroy fortified defensive positions on the coast. On the eve of June 6, Bomber Command employed more than 1,000 aircraft in attacks on 10 coastal batteries in the invasion zone. More than 5,000 tons of bombs, the most yet dropped in a single night, failed to destroy any of the batteries, but some neutralization was achieved. Just three aircraft were lost but one was a Lancaster from 6 Bomber Group RCAF.

The U.S. 8th Air Force arrived over the coast at first light with orders to destroy enemy positions along the beach. Poor visibility meant that pathfinder bomb aimers followed instructions to avoid short bombing and the risk of hitting Allied landing craft. They delayed for up to 30 seconds after the target was identified on radar. The main American concentrations fell well inland leaving the beach defences intact.

The navy took over the counter-battery task and naval guns–assisted by spotter aircraft–were able to complete the neutralization or destruction of all large gun batteries. Unfortunately, the beach defence positions were largely untouched and when the first landing craft arrived the enemy position had to be overcome by infantry supported by tanks.

The elaborate preparations had given the army confidence that the landings could succeed; however, the war diarist of the Royal Winnipeg Rifles only exaggerated a little when he wrote that “the bombardment…failed to kill a single German or silence one weapon.”

The final key to the success of Overlord was to prevent the enemy from counter-attacking the landings or sealing off the beach-head before it could be established in depth. The Germans had stationed just three of their 23 static coastal divisions in the invasion area. However, the powerful 352nd Division had been added to thicken the defence positions near Omaha beach. The 21st Panzer Div., meanwhile, provided a local reserve in the British-Canadian sector. Two other armored divisions, 12th SS and Panzer Lehr, were eight to 12 hours away and other units north of the Seine and Brittany could arrive in the crucial first few days unless Allied air power intervened.

This task of preventing that was the responsibility of 2nd Tactical Air Force and the U.S. 9th Tactical Air Force. 2nd TAF was organized in late 1943 with two composite groups of fighter-bombers, a night-fighter group and one of medium bombers. There were Canadian pilots in many RAF units, but all RCAF fighter squadrons were assigned to 83 Group that was to work closely with the Anglo-Canadian invasion forces.

Apart from 400 Sqdn., which was part of the Photo Reconnaissance Wing, RCAF squadrons in 83 Group were assigned to one of four Canadian fighter wings, 126, 127, 143 and 144. A day- fighter wing consisted of three squadrons of 18 aircraft with a strength of 39 officers and 743 other ranks. 144 Wing was equipped with Typhoon IB fighter-bombers while the other three flew the Spitfire IXB. “Bombphoons” normally carried two 500-pound bombs and were tasked to “provide direct support to the army.”

Spitfires could also carry bombs and frequently did so, but as pilot Hugh Godefroy noted “dive bombing was extremely inaccurate” because “without dive breaks, Spitfires dived so fast that the altimeter went round in a blur.” The pilots could not pull out at exactly 3,000 feet if your instrument could not keep up.

Typhoons were thought to be considerably more accurate in ground attack roles but even here there were serious problems. 2nd TAF created its own operational research section in late 1943 when it became evident that no one knew very much about how to hit relatively small targets.

A study of operations against a viaduct in France that was 500 yards long and eight yards wide revealed that “Bombphoons” scored hits one in 82 times while Typhoons with rockets secured one hit for every 15 fired. Even rocket projectile attacks on gun positions produced discouraging results, varying from 110 strikes at a casement in Courseulles-sur-Mer with zero hits to two hits out of 127 in Fontenay.

Training courses for Spitfire and Typhoon pilots helped improve accuracy against identified targets, but average pilots still had great difficulty in navigating and locating targets. As one tactical memorandum put it: “Fighters, given a six-figure map reference, were unable to spot well camouflaged guns even when the guns were firing.” All of this meant that the tactical air forces were being called upon to perform tasks for which they were not properly equipped. On D-Day the weather further hampered ground-attack operations and those German divisions ordered to the beach-head were able to take advantage of the low cloud cover.

The 12th SS Hitler Youth Div., which had been delayed by confusion and uncertainty, began its advance in the early afternoon of June 6. To minimize losses, vehicles were camouflaged and ordered to maintain 100-metre intervals, but in the late afternoon air attacks disrupted the cohesion of the columns and slowed their advance to a crawl. By the end of that day, 12th SS had suffered 83 casualties, including 22 dead. No tanks had been hit, but none reached the battlefield.

Panzer Lehr, which had much further to travel, did not start its march until the evening. Darkness saved it from continuous attack but by the next morning the two approaching columns were repeatedly strafed, bombed and rocketed. Losses included a large number of soft-skinned vehicles and four tanks, but the tactical air force’s most important contribution was to delay the panzers.

When the division reached the front on the morning of June 8, the 7th Cdn. Infantry Brigade had secured control of the Caen-Bayeux highway and railway line, while British 50th Div. had captured Bayeux. The Allies had secured their beach-heads and were moving quickly to link them together.

Canadian and British squadrons had also demonstrated the meaning of air superiority to the soldiers fighting through the Atlantic Wall. No German aircraft attacked the landings on D-Day and on June 7 when more than a dozen Ju 88s tried to break through to bomb the beaches, pilots of 401 Ram Sqdn. destroyed six and forced the remainder to flee.

The limits of air power were evident, however, when Germany’s 346 Div.–the only unit transferred to the battlefield from north of the Seine–crossed the river and bicycled towards the airborne bridgehead east of the Orne River without interference.

The divisions sent from Brittany to the American sector also reported only minor delays and losses due to Allied air power. The tactical air forces had helped to prevent any serious counter-attacks on D-Day, but they could not stop the enemy from sending enough additional troops to seal off the beach-head. By June 10 the Germans had established a new defensive perimeter that forced the Allies to fight a battle of attrition within sight of the Normandy coast.

The battle would continue to be influenced by Allied air and naval power. On June 7, the North Nova Scotia Regt. and the Sherbrooke Fusiliers ran into the 12th SS near l’Abbaye d’Ardennes. The German counter-attack was broken up by the guns of HMS Belfast which saturated the enemy with tons of high explosive.

On June 12 General Erwin Rommel reported that naval gunfire was so strong that “operations with infantry or panzer formations in the area commanded by this quick-firing artillery is not possible.” Rommel urged Hitler to permit a withdrawal out of range of the warships but the Fuhrer would not allow ground to be given up.

Rommel was equally concerned about the long-term effect of Allied air power. “The enemy,” he wrote “has complete control of the air over the battlefield and up to 100 kilometres behind the front…movements of our troops in the battle area by day are almost completely prevented, while the enemy can operate freely. Neither our flak nor the Luftwaffe seems to be in a position to check this crippling and destructive operation of the enemy air force…”

The Battle of Normandy could not be won by air or naval power, but the air force and navy helped establish the pre-conditions for victory.