There was one more major offensive that spanned 1943 and 1944, and it drew in all available aircraft. Some strangely shaped structures had been spotted in French forests, laid out on a site shaped like a ski, and pointing toward England. The British were understandably concerned.
Daring reconnaissance missions, flown by both British and American pilots, brought back photographic coverage of a 150-mile (240-km) wide belt southeast of London. Photo-interpreters ticked off one ski site after another, identifying 75 of them during December 1943.
There were differences of opinion about the best way to destroy the structures. The British held out for heavy bombers. The Americans thought fighter-bombers at low altitudes could do the job best. They had tests made at Eglin Field, Florida, against replica ski sites, to back their beliefs. But they were overruled, and the heavies were sent out against the forest sites in Operation Crossbow.
On the day before Christmas, 670 aircraft from VIII Bomber Command dropped 1,700 tons of bombs on 23 different ski sites, with good results. The commanders continued to send out the heavies, subtracting their striking power from the Pointblank campaign. Perhaps to hedge their bets, they also dispatched forces of medium bombers and fighter-bombers.
Crossbow attacks lasted until D-Day, 6 June 1944. An estimated 83 out of the 96 discovered sites had been put out of action. It had taken 25,150 bombing sorties that dropped 36,200 tons of high explosives. The cost was 771 airmen and 154 aircraft.
The best estimates of the campaign's effect agree that it delayed the V-1 buzzbomb attacks on London by about three to four months by destroying the launching ramps. It had taken, on average, 436 tons of bombs for each ski site hammered into rubble. Somewhere in the files, there still is a report of the Eglin Field tests in which fighter-bombers dropped thousand-pounders with delayed-action fuses and destroyed replica ski sites for an expenditure of about one ton per site.
When the Combined Bomber Offensive had been first established, it was given a finite life span. The end date was 1 April 1944; on that day, the CBO officially and legally ceased to exist. A few more missions were flown against Pointblank targets, but for all practical purposes that part of the air war was over.
The United States Strategic Air Forces, consisting of VIII Bomber Command and Fifteenth AF, were placed under Supreme Headquarters, Allied Expeditionary Force (SHAEF), commanded by General Dwight D. Eisenhower. They were joined by RAF's Bomber Command, and by the Allied Expeditionary Air Force, a tactical organization consisting of the RAF's Second Tactical Air Force and the USAAF's Ninth Air Force.
Now the task that faced them was the final drive on behalf of Overlord, the invasion of Europe. They had only a few weeks left to accomplish that mission.