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Manchester AU
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Author:  Sheepster [ September 27th, 2020, 5:32 am ]
Post subject:  Manchester AU

While working up the Avro Lancaster family tree 3(!) years ago, I drew the pre-war proposed Manchester turret cannon prototype that was never completed, and thought “if it had been built in numbers, and if Britain had used it like the Americans used AC-47 Spookys in Vietnam, then the panzers would have been halted in 1940”.
So, making a few minor (I think) tweaks to history, I built a scenario that allowed just that. Halting the blitzkrieg would have significantly changed the world (particularly aviation), so I followed that alternity with logical extrapolations from the historical record, and wargame simulations (to keep it neutral and not stray into the realm of luft46, British Imperial, Pax Sovietika, or any other fanboy land). And I must say digging into information from the minutiae of 1940 diplomacy to industrial design and production was fascinating in revealing the world everyone was expecting for 1941 and beyond, a potential world that was crushed under the panzers’ tracks. As I worked through the uchronology though, this alternity drifted as far away from expectations as our own.
What follows then is the alternity I’ve labelled the Manchester AU. It includes some models and schema that were in our “reality”, built models that received a different history in this different world, designs that were still-borne for us but given life here, and models designed under the operational philosophies of this new world – but still from the logical growth of pre-Case Yellow designing. I’ll include historical backstory, making no mention of divergences from our “reality” (just as there is no Wikipedia editorial to say “if the US aircraft carriers had been moored up in Pearl Harbor then this would have happened …”).
Some of the illustrations contain individuals’ names. These are the genuine heroes, of whatever force or nationality, that operated either that specific machine at that time in our alternity, or operated the alternity’s equivalent machine in the alternate action. As the split between us and them widens names lose relevance and disappear.

Avro Manchester history in our alternity:
01-July-1937 – ordered straight from the drawing board, the contract was signed from 200 aircraft, with a clause for an additional 200 aircraft for 20-09-1939. Avro engineers were concerned by the RR Vulture engines specified in Spec.13/36, and so considered alternate powerplants, including the Bristol Hercules.
04-August-1937 – it was decided that the first Manchester prototype was to be fitted with already in production Bristol Hercules engines, with the second fitted with RR Vultures.
15-May-1939 – due to concern about the ability to machine-gun armed bombers to defend themselves, a conference on the design of powered heavy cannon turrets was held on. As the most suitable airframe, the Manchester was chosen to develop the concept.
25-July-1939 – first flight of the prototype Manchester, with poor engine performance from the Vultures and poor directional stability noted immediately.
21-September-1939 – Avro announced that the Manchester Mk.II (turret armament development aircraft) fuselage design was largely complete, awaiting the turrets.
25-May-1940 – cancellation of B1/39 “Ideal Bomber”, F11/37 turret fighter, and further work on 20mm turrets.
05-August-1940 – delivery of first production Manchester.
24-February-1941 – first operational sortie by 6 Manchesters.

Author:  Sheepster [ September 27th, 2020, 5:36 am ]
Post subject:  Re: Manchester AU

Divergence

With the awarding of the initial Manchester contract expecting 200 aircraft to be delivered in just over 2 years, Avro embarked on a “priority design programme”, committing all efforts to design and production of the new aircraft. As a priority design, the secondary requirements for dive-bombing, torpedo bombing, and catapult launching were removed – simplifying and expediting the design process. Due to the concerns of the availability of the new RR Vulture engine, all initial design work was undertaken using the Bristol Hercules engine, even though the Hercules models then available were 200hp lower than the power promised from mature Vultures. Understood to be a reduced payload airframe until the Vulture was sufficiently developed to be fitted operationally, the reduced payload from a Hercules-powered Manchester was accepted with the initial production aircraft.
The first production Manchester’s rolled from the production line in May 1939, with adequate performance at the accepted lighter weights, but with relatively poor directional stability. Work immediately commenced redesigning the twin vertical tailplanes, quickly leading to an increase in tail height.

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As the first Manchester began flight trials, concern from the Air Ministry over bomber defensive armament led to Avro being given instructions to redesign the Manchester to take dorsal and ventral 4 cannon turrets. The revised airframe, with a swollen mid-section to take the 10ft diameter turrets, was designated the Manchester Mk.II and immediately entered production, replacing the Mk.I, with the weight of the new turrets further eroding the available payload. As the Bristol “Ideal” heavy bomber was also to feature the same turrets, the relegation of the Manchester Mk.II to become a complementary medium bomber was considered acceptable to confirm the defensive concept of the heavy turrets.
The first Manchester Mk.II’s were available for delivery to squadrons in December 1939. With the RAF Advanced Air Striking Force deployed in France alongside the British Expeditionary Force, Manchester Mk.II’s were sent directly to the AASF to start replacing Fairey Battles as frontline bombers (after Air Chief Marshall Brooke-Popham’s audit the Fairey Battle was seen as under-armoured and underarmed). Retired Battles were eagerly taken over by Belgium and South Africa. Twelve aircraft were flown directly to Belgium, where the aircraft were not modified to Belgian standard, merely having their RAF roundels overpainted before being sent directly into service.

Author:  Sheepster [ September 27th, 2020, 5:38 am ]
Post subject: 

10th May 1940

The 10th of May 1940 was a very momentous day for Great Britain. Operation Fork landed British forces unopposed on Iceland to secure the Danish territory from a possible German invasion, the Danish Faroe Islands had already been occupied on the 12th April. In Westminster, Neville Chamberlain had come to terms with the fact that he had lost the confidence of the House and would have to step down as Prime Minister. Although news from the Continent gave him pause, by 6pm the King had offered the Premiership to the House’s second choice for successor, Winston Churchill.

Author:  Hood [ September 27th, 2020, 9:33 am ]
Post subject:  Re: Manchester AU

I look forward to seeing how this pans out.

Author:  Sheepster [ September 28th, 2020, 4:30 am ]
Post subject: 

Fall Gelb – Case Yellow

German action to her west formally commenced before dawn on Friday 10th May 1940, although German agents had been positioned earlier under the flimsy guise of “tourists” and “merchants”. The attack was not unexpected with multiple warnings being provided from sources including Pope Pius XII.
Germany’s assault plan comprised 3 thrusts, with a goal to lure the Anglo-French forces into Belgium and trap them in a pincer action. Army Group B was tasked with initiating the invasion, advancing through the Low Countries and bringing the Entente forces to battle in Belgium. A secondary action was to capture the Netherlands to deny Britain the use of Dutch airfields and instead have them available to the Luftwaffe. The largest and strongest force of Army Group A was to push through Luxemburg and the Ardennes, striking into France at Sedan and moving through the French rear to deliver the decisive blow.
The German officer corps were horrified at this offensive plan, seeing the concentration of forces without adequate supply trains as too high a risk. If the Entente forces did not react as expected, the offensive could end in catastrophe with the destruction of the panzer force. Hitler’s desire for a decisive armoured breakthrough as a repeat of the Polish campaign, over-rode the objections of the Generals who did not consider that the style of warfare would succeed against a first-rate military like the French.

Author:  Sheepster [ September 28th, 2020, 4:35 am ]
Post subject: 

A major requirement for the rapid deployment of troops in Europe was rapidly securing strategic bridges and crossroads. As such amongst the first ground actions were deployment of airborne forces to advance positions, with four simultaneous landings just after dawn in the Netherlands, Luxemburg and Belgium.

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In Rotterdam 12 Heinkel He59’s from the secret Sonderstaffel Schwilben, a unit formed solely for this mission, landed in downtown Rotterdam, and to the amazement of the city’s populace offloaded two platoons of German troops who paddled ashore and captured the Willemsbrug across the Nieuwe Maas river. On the restricted water of the river 2 aircraft collided and sank, while the others were able to return to German, albeit all with combat damage.

Simultaneously paratroops attempted to capture Dutch airfields to secure them for arriving Ju 52 troop transports and other strategic points. Landings were made at Ypenburg, Valkenburg and Ockenburg airfields, and on the motorways at Delft and Hoek van Holland. Initially the Germans had some success capturing the airfields enabling second waves of Ju 52 transports to land to disembark more troops. However a strong defence from the Dutch, including using armoured cars against landing and landed aircraft, led to theses airborne assaults all failing during the day, with massive losses of killed and captured German troops and significant loss of airborne transport capacity to the Luftwaffe.

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While the Rotterdam mission achieved its initial objective, no other forces were able to assist, leaving the German assault teams isolated at the bridge for several days.

Author:  Sheepster [ September 29th, 2020, 6:45 am ]
Post subject: 

The Belgian initial defence line was based on the Albert Canal, with its bridges as the only means for armour to advance into Belgium. Guarding the area the Belgians had constructed a set of modern forts, the largest being Fort Eben-Emael. Neutralising the fort would be vital to either capturing the bridges, or if the bridges had been destroyed deploying temporary canal crossings. Initially a paratroop assault was considered, but as a tight drop onto the fort itself would be unrealistic, this plan was rejected. Hitler personally ordered the use of gliders on advice from Hanna Reitsch. Fifty DFS 230 assault gliders were allocated to the force, and absolute secrecy was maintained during training and deployment. Using the element of surprise, the assault force was to be split in to 4 forces, Group Granite attacking the Fort, while three other groups tasked with capturing 3 bridges, then holding these positions until relieved by the advancing German forces.

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The gliders were dropped 20 miles from their targets, and although their approach was silent, the Ju 52 tow-planes alerted Belgian anti-aircraft defences which opened fire. The flight profile of the gliders was a dive-bomber-like 80* dive, followed by a short landing, aided by the extra friction of barbed wire wrapped around the landing skid. Even with anti-aircraft fire only one glider was shot down, and the majority of the gliders landed exactly as planned.
The assault was a success for the Germans, with 2 of the bridges captured before Belgian demolition charges could be detonated, and with the Fort successfully neutralised. Although the plan had been for the assault force to be relieved within a few hours, delays due to heavy Belgian resistance led to relief only the next morning.

Author:  Sheepster [ September 29th, 2020, 6:47 am ]
Post subject: 

The two airborne assaults on Luxembourg and south-eastern Belgium were unrelated actions undertaken by the most unexpected assault force transport aircraft, Fieseler Fi 156 Storches.
Luxembourg had no significant military forces, and was considered to be merely a transit route for German troops to north-eastern France for the pincer move. As such control of crossroads to prevent bottlenecks in German movement was vital. Named Operation Hedderich, the task of transferring 125 German commandos to five locations along the Luxembourg/French border was given to a fleet of 25 Fieseler Fi 156 aircraft. Flying in in 2 waves, the short landing ability of the Storches allowed the troops to be positioned successfully, and fortuitously, as the small force was able to repel the probing of the French 13th Motorised Brigade into Luxembourg. But even with control of the intersections traffic jams ensued.

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Another secret unit was formed for a similar but larger operation into Belgium, Aufklärungsgruppe 156, being disbanded afterwards. Due to the two target areas, Nives and Witry, the mission received the name Operation Niwi. Approximately 100 Storches were allocated to fly in 2 groups at low level across central Luxembourg to their target areas in Belgium, and then to return to Germany and fly in a second wave. Due to a navigational error only 5 aircraft of the first wave reached Witry while the remainder of the southern force landed close to Nives. While the operation achieved its objectives of securing the area, by disrupting communications to Belgian forces the German advance was delayed, a withdrawal order was not relayed to a company of the Belgian 1st Chasseurs Ardennais who remained in place to defend Bodange.

Author:  Sheepster [ September 29th, 2020, 3:15 pm ]
Post subject: 

Battle Of The Netherlands, 10-14 May 1940

On the night of the 10th lead reconnaissance elements of the French 1st Mechanised Light Division crossed into the southern province of North Brabant with Panhard 178 armoured cars. The French force attacked the German bridgehead at the Moerdijk Bridge the next morning, to enable a link up with the Dutch army. With heavy bombing by Stukas, the French force was beaten back. By noon on the 12th the lead elements of the German force made contact with the Moerdijk bridgehead, removing all hope of the French main force reaching Rotterdam. By 1400 all French troops were ordered to withdraw to Antwerp.

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The Dutch also requested army and air support from Britain, but neither was available in strength before the 16th. On the night of the 11th “Harpoon Force” was landed at Hoek van Holland, but with the purpose of safeguarding evacuees (including the Dutch royal family if required), and destroying Dutch installations and fuel reserves to prevent their falling in to German hands – rather than assisting in the defence of the Netherlands. Having an independent British force tasked with destroying Dutch resources while the Dutch were trying to defend them shocked the local Dutch commandeers, but the British operation was poorly planned and the force was poorly resourced, and did achieve the demolition goals before the 14th.
The Dutch Air Force were crippled on the first day of hostilities, losing half their aircraft before the sun set. The last action by the last flying Dutch bomber was a last-ditch attempt to knock out the Moerdijk Bridge early on the morning of the 13th after all other attempts to stop the advance of German armour towards Rotterdam had failed. Bombing from low level, the bridge was hit but the bomb did not detonate. The last bomber was shot down by German fighters.

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The Dutch Army was undertrained and suffered from poor tactics and poor command, and although German efforts were successful overall, their advance suffered numerous setbacks and delays, and was very costly in terms of both men and equipment.
By the morning of the 14th the Dutch defensive lines had failed, and German forces had captured most of the Netherlands, except for the coastal provinces and Utrecht, including the city of Rotterdam.

Author:  Sheepster [ September 30th, 2020, 11:31 pm ]
Post subject: 

Battle Of Northern Belgium, 10-12 May 1940

Likewise in Belgium, the Belgian Airforce also lost almost half their aircraft on the first day.
With the failure of the primary defensive line at the Albert Canal, the Belgian Air Force attempted to bomb the bridges and German positions. Supplemented by their newly acquired Fairey Battles and escorted by Gloster Gladiators, the Belgian force was badly mauled by Bf 109’s and intense ground fire without significant impact to the German advance.

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The fall of the Albert Canal defensive line led to Belgian forces being pulled back to the secondary defensive line five days earlier than pre-war planning expected. As the Anglo-French forces had to advance from France, they had minimal time to advance and also prepare an effective defensive position in Belgium. While the French 1st Army advanced to a create that defensive line at Gembloux, the French Cavalry Corps was tasked with advancing further east to Hannut to delay the German advance, giving more time for the defensive preparations.

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