THE BIRTH OF THE JET BOMBER

During the 75+ years since the Second World War, the story of the jet bomber can be divided into three distinct evolutionary phases. Phase 1 was from 1945 to 1960, a period of revolutionary change and the transition from piston to turbojet at a time when strategic deterrence relied on a concept of ‘massive retaliation’ with nuclear weapons.

Phase 2 was from 1961 to the 1970s when ‘flexible response’ and burgeoning anti-aircraft defences brought bombers down to low level for high-speed penetration, with both avionics and systems integration maturing. Phase 3 is the period from the 1970s to the present, where stealth, airframe shaping, new materials and advanced avionics have influenced both design and deterrent policy.

Threat assessment has shaped the path followed by planemakers and engine manufacturers but the route was mapped by advancing technologies and shifting geopolitical challenges. Phase 1 set the strategic bomber at the core of US defence policy, even at some expense to land and sea forces.

During this period the US government spent heavily on new technologies and infrastructure for a global bomber force. Foreign bases proliferated and the jet bomber underpinned a new globalisation of American military might.

Phase 2 saw a transition away from the jet bomber to intercontinental ballistic missiles (on land and at sea) for the nuclear delivery role. Bombers now offered a more flexible application of air power, increasingly challenged by massive air defences. Not a single new bomber made it into service during this time – costs soared, questions were raised regarding the efficacy of massive air power and technology began to reshape the dynamic of combat air power.

Phase 3 was itself shaped by shifting challenges, new technologies which returned the bomber to the deep penetration role and by a reprogrammable application of both conventional and nuclear weapons.

Much of what happened within the American aviation industry during these three periods arose from three separate capabilities – general capability in design, development and production; the capability to make key systems, subsystems and technologies; and the unique capabilities of individual companies.

During each of the three chronological phases, the bombers built depended on both the capabilities available and the existing and projected future military needs of the USAF.

The Jet Age

The end of the Second World War heralded a transformation in combat aircraft design, performance and capability. The jet engine allowed both bombers and fighters to reach hitherto undreamt of speeds and spurred technological innovation in other areas of airframe and equipment design.

Some of this innovation resulted from the capture of laboratory test results and wind-tunnel trials data from Germany. Before the D-Day invasion of 6 June 1944, German progress with jet and rocket powered aircraft was well known from extensive reconnaissance photography of airfields and research establishments combined with signals intelligence and reports from agents and partisans inside occupied territories across continental Europe.

The world’s first operational jet fighter, the Me 262, was seen in the skies over Europe not long after D-Day and the last enemy aircraft to fly over Britain had been a German jet bomber – the Arado Ar 234 B-1, on 10 April 1945. Initially designed as a pure reconnaissance platform, the bomber variant of the Ar 234 became operational in September 1944 and quickly impressed the Luftwaffe. Its sheer presence was a sobering display of muscular technology already in production and on the flight line.

With its distinctive ‘greenhouse’ nose, high wing mounting on the upper fuselage and single jet pods in the mid-wing position, the Ar 234 was also developed into a night fighter version with four paired BMW 003A-1 turbojet engines. Sleek and fast, it had the potential to worry the Allies but the war ended before its potential could be realised.

Impressive yet under-developed and bedevilled by under-performing and unreliable engines, along with the Me 262 and the Heinkel He 162 it sent a clear and distinct message that the jet age had arrived.

Yet the Allies had not been idle in developing their own jets. The last two years of the war saw a flurry of requirements for new jet types by both the US and Britain. British jet engine inventor Frank Whittle and his company Power Jets test-flew their creation in the Gloster E.28/39 in 1941 and the technology was soon handed over to the Americans.

Together with American companies’ own engine developments, this resulted in several competitive projects – all of which stimulated a surge of interest in applying jet propulsion to fighters, bombers and reconnaissance aircraft.

There were widely differing opinions as to the efficacy of the jet engine at first. Vast manufacturing plants were already churning out thousands of highly developed and highly successful piston engines. These had powered the fighters and bombers that won the