Classic Aircraft profiled every issue -

Issue 8 - Boeing B-17: Shaping the bombers

During World War One Germany used Zeppelin airships and later Gotha aircraft to drop bombs on targets in Britain. These attacks included the serious bombing of coastal towns and London itself. War had been brought to civilians who were far removed from the battlefields. It was the Gotha raids on London that spurred the government of the day to improve aerial defences of the capital and to retaliate in some manner. Work was quickly completed on suitable long-range bombers but before the newly-formed Royal Air Force could take the war to the heart of Germany the Armistice was signed and peace returned.

In the years of peace during the 1920s there was no urgent requirement for new long-range bombers, but light bombers were introduced to quell any skirmishes that arose in the British Empire, these were mainly in the Middle East and on the Indian frontier. Only when peace appeared to be threatened in Europe by Germany did Britain take heed and rush to have new aircraft – fighters and bombers – of a modern type designed and built. What was sanctioned for the RAF were light and medium bombers nothing that could be classed as a heavy strategic bomber was considered even though designers provided plans for such types.

Across the Atlantic the United States had been left on its own to pursue its own agenda in aircraft design. Even though the Wright brothers gave the world powered flight in 1903 the US had not capitalised on the invention and had to make do with French and British aircraft during World War One. After the war they developed their own types but concentrated on civil transports and neglected their armed forces. Bomber aircraft were simply not considered important despite the urging of some senior officers, the most vociferous being General William Mitchell who was eventually court-martialled for his outspokenness.

After the Armistice, Germany had been banned from developing anything but light sporting and small commercial aircraft. However, they were looking to establish an armed air force and German designers were at work outside Germany producing potential war machines. By the end of the 1920s the Allies had lost interest in Germany and chose to ignore or were largely unaware of what was going on in that country.

Consequently, when the new Chancellor, Adolf Hitler, took office he immediately began to build up the armed forces as he had promised. All three services were the subject of improvement with the Luftwaffe gaining new aircraft. It was a time of rapid expansion with fighters and medium bombers being given priority. Hitler did not require a long-range strategic bomber at the time, there were plans for heavy bombers but that was for the future. For the present it made sense to concentrate on aircraft that could reach most of Europe with a reasonable bomb load. England was never in Hitler’s scheme of things in the 1930s and North America was well out of range of any Luftwaffe’s aircraft.

Spurred on by the events in Europe Britain began to re-arm and indeed started to do so before Germany got fully into its stride of building up an arms base. Work was already in hand by Handley Page, Vickers and Armstrong Whitworth who all produced medium or heavy bombers by the middle to late1930s. Fairey designed and fielded the Battle light bomber which was a capable aircraft but woefully underpowered, as was discovered when it went into combat. Waiting to emerge in the really heavy bomber stakes was the Short Stirling, the RAF’s first four-engined heavy bomber, which would go into service before the Handley Page Halifax and Avro Lancaster but would suffer due to its limited operational service ceiling.

The United States realised that their air force was outdated and their fighters, or ‘pursuit ships’ owed more to aircraft from World War One than anything in Europe. It was not the aircraft designers and manufacturers who were at fault but those in command who were behind the times. Not helping was the severe depression of the 1930s, purse strings were pulled tight and existing aircraft designs had to suffice in the US Army Air Corps (USAAC). With a new president in the White House and a plan for investment in the country, matters took a turn for the better.

To get the country moving again American industry had to be encouraged and modern equipment for the armed forces became a priority. By 1934, it was quite obvious that the Martin B-10 twin-engined bomber was quite outmoded and in desperate need of replacement. An open competition to US aircraft manufacturers was announced for a multi-engined replacement to the Martin B-10. Proposals were submitted and in May 1934, Boeing and Martin were chosen to build what were to be the first four-engined bombers to be ordered by the USAAC.

In the event the Boeing XB-15 was shown to be the superior proposal and the Martin was cancelled. However, the XB-15 was massive and took time to come to fruition. In the meantime, Boeing fielded their Model 299 which was also entered for the bomber competition and made rapid progress in construction. It first flew on 28 July 1935, two years before the XB-15. The aircraft was heavily armed and intended to defend the fortress US against any enemy invasion.

The idea was that the aircraft would attack the enemy fleet long before it could get within striking distance of the US mainland. Given the job description and the fact that it carried so many guns it was not long before the name ‘Flying Fortress’ was coined by the press of the day and adopted as the official name for the Boeing B-17. However, Congress did not want to spend any money on buying the aircraft and only a handful were ordered at first; then Hitler invaded Poland and the USA realised that war could be a reality. Re-armament went into top gear with the B-17 being ordered in larger quantities.

Britain had gone to war and initially attacked German targets by day but the losses incurred were unacceptable. RAF Bomber Command switched to night operations which saw a drop in the number of aircraft lost on missions. This decision was to shape both the future of the aircraft and the service. Early in the war, Britain carried out some 15 months of negotiations with the USA for the B-17. Finally in 1941 20 B-17Ds – known as the Fortress I in the RAF – were ferried across to be modified for Bomber Command. They were issued to No 90 Squadron at West Raynham in May 1941 and commenced operations on 8 July, when three Fortresses bombed Wilhelmshaven from high altitude. Further missions followed against various targets in Germany and the occupied countries, all were flown in daylight and were not that successful. Bomber Command withdrew the surviving Fortress Is from Europe and deployed four to the Middle East.

Meanwhile, the first of the B-17s belonging to the US Army Air Force (USAAF) arrived in Britain on 1 July 1942. The Americans had their own ideas on how to mount raids against the enemy and refused to take on board the experience from Bomber Command of nearly three years of operations. It was agreed that the USAAF Eighth Air Force and the RAF would wage a day and night offensive against German targets; the US by day and the British by night. On 17 August the USAAF carried out its first raid when 18 B-17Es attacked railway yards and coastal targets in France. Most of 1942 was spent in training and other raids into German-held territory but it was not until January 1943 that American bombers flew against targets in Germany itself.

At first the USAAF operated their bomber streams in loose Vee formations at varying heights, but this proved to be vulnerable to enemy fighter attacks as not all the guns of the bombers could be brought to bear for fear of hitting other aircraft in the formation. The formations were tightened and this improved firepower but made it difficult for the aircraft to manoeuvre quickly to avoid enemy fighters. Aircraft formations continued to be changed and improved to enable all guns a clear field of fire. Losses were still high despite the changes to tactics and it was not until the long-range P-47 and P-51 escort fighters came into service towards the end of 1943 that matters improved dramatically.

There is little doubt that the bombing of enemy targets by the RAF and the USAAF had a deciding effect on the outcome of the war. While it was not strategic bombing as we know it now, the continuous attacks did have a devastating effect on the enemy. For example, by the last year of the war Germany had little or no fuel for vehicles and aircraft and raw materials in general were in short supply.

The lessons learned from the Allied bombing campaign in Europe, and to an extent in the Far East would shape the postwar role of the bomber that has continued to evolve right up to the present day.

Words: Francois Prins