The success of the allied campaign to break the Luftwaffe in February 1944 gave some relief to the long suffering bomber aircrews of both the RAF and USAAF. However the relief was to be short lived and especially for the RAF who found the cover of darkness to be more of an advantage to the enemy than themselves.
As early as late October the previous year there had been vague reports of concentrated Flak in areas previously designated as being light to moderate. The main concern was the length of these so called Flak corridors which, in the report of one RAF crew, “just seemed to go on forever right up to the target”.
German high command had issued a directive to bolster the anti-aircraft defences of the Reich in mid-1943 and poured resources into the development and manufacture of Flugabwehrkanone. It was at this time that the inspirational, yet almost seemingly obvious once actioned, decision to mount anti-aircraft weapons on manoeuvrable aerial platforms lead to the development and deployment of hundreds of Schwebewaffenträger , code named magic carpets and referred to as “rolling thunder” by the USAAF.
The Luftwaffe quickly integrated this new and potent mobile anti-aircraft weapon into the Reich defence system which were now able to monitor raids and vector both aircraft and Schwebewaffentrager units from holding positions into the path of the oncoming stream. Schwebewaffentrager operated at low level and were unable to keep pace with the stream but were available in sufficient numbers from the Rhine to Berlin to be called and repositioned as the raid progressed.
As soon as target prediction confidence grew more Schwebewaffenträger were moved into an intercept position upstream of the raid and began tracking forward. This is where the allusion of endless flack batteries engaging the stream came from. Bomber losses began to creep up and moral began to suffer.
The USAAF began sending whole groups of aircraft in addition to that of the Bombers and escorts solely to deal with the Schwebewaffenträger which was a dangerous job and not at all easy. It did however keep the German gun crews busy and so give some respite to the bomber crews. At night it was almost impossible to engage the German Flak barges and so RAF bomber command losses began to rise.
The mainstay of Bomber Command by late 1943 was the Roy Chadwich designed Avro Winchester which was a development of the disappointing earlier Avro Salisbury. The Winchester had 4 x coupled thrust units mounted in pusher configuration with 2 x additional power only units in sponsons placed just behind the crew cabin. These two additional power units were to augment EMFEM generation and allowed for the ever increasing loads the Winchester was required to carry to targets deep within Germany.
During 1942 Chadwick had been present at the demonstration of the shielding capability of a downed FW390 Dolch at Farnborough and had been impressed. The Dolch produced 50% of its lift from conventional aerofoil surfaces therefore freeing up a great deal of the energy production from its V24 power unit that would have otherwise been needed for lift/weight reduction.
Aero Electric applications had improved speed, range and load lifting especially in transport and bomber aircraft but required huge amounts of power. The USAAF had the 6 engined B229 which had limited shield capability but was found to be in a never ending charging cycle once in the combat zone where its shield defence was negligible.
Chadwich’s thoughts were along the lines of just completely forgoing electrical lift by using full aerofoil section wings and maximise on load lightening via EMFEM and producing “bags full” of power for shielding.
To maximise the lifting area Chadwick filled in the section between the sponsons and the winglets giving a delta form to the lifting surfaces. To this were added 4 x Tesla-Royce Merlin Electric 850 non thrust power units in common nacelles that reached back to the 4x similar but coupled thrust units and housed the Tcoils, power conditioners and undercarriage. Fuel and shield generators were stored within the ample wing area.
The Avro production team nicknamed the prototype the flying power station and management toyed with the idea of naming the aircraft the Battersea but the air ministry intervened as they often do and renamed the aircraft the Avro London.
Final structural changes to that of the Winchester was the removal of the dorsal turret and a slightly more robust undercarriage.
The bomb load remained the same as the Winchester which was not inconsiderable but the surplus power generation capability of the London gave the RAF a bomber with full close skin ballistic shielding - “a war winning aircraft” as the propagandists news reels would state.
The truth is a little more down to earth of course. That’s not to say that the London was a failure of which it wasn’t by any means. It was however at the cutting edge of a brand new technology and there were often part shield failures and sometimes these failures would become total.
It is not correct, as is sometimes stated, that the shield projection did not suffer from recharge lag. It did and more often than not an aircraft could be at best 85% shield capacity for most of its time in a “hot zone”. In addition, absorbing the blast from a salvo delivered via 12.8 cm Flakzwilling 40/2 not only drained the shields but caused skin damage which in vital places could prove deadly.
The Germans referred to the Londons as Shield Maidens and despite the teething troubles and on-going problems they did reverse Bomber Commands losses to something more manageable. Its crews swore by it and its grounds crews swore at it but all in all the aircraft became a legend.
It is worth mentioning that in the future when more exotic power generation is available and shielding technology more mature, the deploying of shields is still known as “going to London”
