Tuesday 21 February 2017

Also No Reason

I am not a Know-Nothing. That is certain. How could I be? How can any one who abhors the oppression of negroes, be in favour of degrading classes of white people? Our progress in degeneracy appears to me to be pretty rapid. As a nation, we begin by declaring that "all men are created equal." We now practically read it "all men are created equal, except negroes." When the Know-Nothings get control, it will read "all men are created equal, except negroes, and foreigners, and catholics." When it comes to this I should prefer emigrating to some country where they make no pretence of loving liberty-to Russia, for instance, where despotism can be taken pure, and without the base alloy of hypocrisy.

-Abraham Lincoln

Tuesday 14 February 2017

Amerika Bombers II: Vague Plans and Flying Boats


Last time on Amerika Bombers, we briefly reviewed why the Nazis had large problems building a strategic bomber. Germany lacked the resources and industrial capacity to build a fleet of strategic bombers. In an attempt to get around their material difficulties, they commissioned a heavy-ish bomber of supreme technological ambition, the Heinkel (He) 177. This bomber would turn into a disaster while in development, and it would, along with the lack of strategic bombers, would cause caused large problems for the Nazis during the Second World War.

This post will be about the prewar Amerika bomber plans, such as they were, and anything related that crops up during 1939 and 1940. The first formal interest the RLM paid to trans-Atlantic warplanes was in early 1939, when Hermann Goering himself inquired what could be done in the way of a bomber for 'nuisance raids' against the US East coast. This inquiry was met with gentle skepticism for obvious reasons, though it appears some staff work was done on the question. While I'm inferring the conclusion of this staff work, the ways to bomb America via current technology amounted to a simple choice:

Option A. Develop a bomber of enormous size and complexity to make the trans-ocean voyage. This would take several years, engines that did not exist currently, and may or may not produce a viable military aircraft.  A flight from Bordeaux to New York and back was 6000 km each leg, call it 12,000 km; with a fuel reserve of 10%, 13,200 km. If you wanted to cover the eastern seaboard down to the Georgia-Florida state line, you'd have to add an additional 1000 km each way; call it 14,000 km plus a 10% reserve = 15,400 km, within spitting distance of the later B-36's herculean range of 16,000 km. One advantage of going the literal extra distance is thanks to the geometry of the Earth, such an airplane would also have the range to cover much of the industrial heartland of the North-Eastern United States, as well as the industrial center of Canada. [Canada was a target that as far as I can see was never mentioned by the Germans; I thought I'd just bring it up.] This at least gave the hypothetical aircraft utility as a broad-ranging intercontinental bomber.

7000 km range, from Bordeaux, France.
A bit of trivia: an Amerika bomber that could bomb Savannah, Georgia could also bomb Winnipeg, Manitoba, or Saskatoon Saskatchewan.
On the quite considerable other hand, aircraft had just started to be developed that could fly across the ocean without stopping; and these, of course, were civilian aircraft. Developing an airplane that could cross an ocean to a hostile continent and return was something else altogether.  The range of the Fw 200 Condor was 3500 km, and this was near state of the art. 'Daunting, even to Nazi optimism' is not a phrase you come across often, but, welp, here we are.

Option B. Every other method less strenuous than Option A. This is a deep, almost bottomless well of ideas for making aircraft that could accomplish anything from a 'Doolittle' style raid (IE a one-shot raid aimed a damaging the enemy's morale) to the "nuisance" style attacks Goering was talking about. (IE raids that while doing not much real damage, took enemy resources to defend against.) Ideas for accomplishing this include refueling big flying boats mid-Atlantic, getting use of the Azores from Spain, developing aerial refueling technology to boost the range of as-yet undeveloped heavy bombers, etc.

It may strike you as strange that I've dumped these all together into a big bucket of ideas, but they all have a few things in common. First, they are all cheaper than Option A. Second, unlike Option A, if the development of a new aircraft is required, it is likely to be an aircraft with more than just one mission, which means it might be possible to synergize the development of an Amerika bomber with some other Luftwaffe program. Third, nearly all the options have a huge number of complications, things to verify and test, techniques to be developed, etc. To make matters even more complex, almost none of the ideas under consideration were mutually exclusive, so people could consider multiple ideas working together.  Option A had one advantage, in that it was almost linear in its simplicity: either engine could be built that could do the job required, or not - either the ROI of developing a huge bomber for this mission made sense or it didn't. Option B, in contrast, had so many possibilities the failure of one possibility simply made another more favored. This seemed like an advantage to the RLM; in truth, it was a cost.

If you were a staff officer of the Luftwaffe charged with assessing these options, you'd then turn to German aviation firms to see what they had on the drawing boards along these lines. With one firm as an exception, you'd discover some good news and bad news. The good news is that there were, in fact, plenty of trans-Atlantic aircraft in the planning stages. The bad news is that all of these aircraft were civilian. With the Nazis in the pre-war phase almost universally hostile to large aircraft, development of anything really large was usually a civilian project. What's more off-kilter about this is that these civilian designs were often developed with very little thought to militarization. Most large aircraft the Nazis fielded in World War 2 were either civilian models pressed into service, like the Focke-Wulf 200, or were military models developed from civilian predecessors, like the Junkers 290. German Aviation firms were also eager to find new markets aside from the Nazi government.

One final wrinkle in all this was that many of the large aircraft that were being drawn up by German aviation firms were large flying boats. Most long distance airline routes favored flying boats as they required very little in the way of specialized infrastructure. A sheltered bit of water to land on was widely available, as opposed to modern concrete runways, and landing on water scaled up very simply as well - aviation designers were free to dream as big as they liked, without having to worry about airport facilities.

Dornier, for one. Having already constructed large flying boats before, they were working on a flying boat with a maximum takeoff weight of 145 metric tons.

Dr. 'Willy' Messerschmitt.
The Last Name in German Aircraft

But before I  start going all flying-boaty mcboatface, let's talk about the exception to the civilian drift of German long range aviation:  Messerschmitt, specifically Dr. Willy Messerschmitt. The designer of the Bf 109, the standard German fighter throughout World War 2 as well as many other famous aircraft bearing his name, was interested in large bombers, even before the Second World War started. Messerschmitt was aided in these interests by his social connections; simply put, he was the only aircraft engineer who circulated in the highest circles of the Third Reich. Being able to bend the ear of Adolph Hitler about whatever you wanted to work on was a significant advantage in Nazi Germany - it's also possible that Messerschmitt was savvy enough to recognize Hitler would have a hard time turning down a pitch involving "ocean spanning super bombers".

At any rate, Messerschmitt in the late 1930s had several design studies going on, exploring very long range aviation, typically achieved by high flying. Messerschmitt hoped that by flying high and maximizing the efficiency of the air frame, an airplane could be constructed with gigantic range, but with less than gigantic size. Two of these projects would see the prototype stage: the P.1061 and the P.1062.

A Me 261, captured in 1945.

 P. 1061 got the resources to reach the prototype stage for the oddest of reasons. Paper calculations projected the world's best reconnaissance aircraft of 1940, but what got P. 1061 a designation from the RLM was the Olympics. Germany had hosted the Olympics in 1936, and in 1940 it was to be hosted in Tokyo. Some bright eyed Aryan (it might have been Messerschmitt) had the idea of demonstrating the might of Fascism's blossoming flower by constructing an airplane to fly from Berlin to Tokyo direct with the Olympic torch. Resources were stretched too tight for the world's best recon aircraft, but building an aircraft to courier the Olympic torch was doable.



The prototype was given the name Me 261 in the spring of 1938, with wind-tunnel tests starting later that year. The problems were, as always, with the engines: while any number of forthcoming 2000+ horsepower engines had been penciled in as the powerplant choice, the engine closest to exiting was the Damiler-Benz 606 - the same "power unit" that was supposed to power the He 177. If you read the last post, you know that this engine is infamous for being a failure, with chronic reliability problems. Another problem was that the DB 606 was still under development and, more importantly, prioritized for the He 177. Assuming a reliable engine, the Me 261 would have been staggeringly difficult to intercept for most Second World War era fighter planes: Messerschmidt had designed the Me 261 with very large propellers specialized for high altitude cruising, which would have allowed the Me 261 to retain its speed at high altitudes. The Me 261's extremely high aspect ratio wings, too, would have preserved its maneuverability in the upper atmosphere, even as would-be interceptors were stalling themselves by turning. A final design detail notable in the Me 261 was its gigantic low-pressure "tundra" tires on its landing gear. The Me 261, being a tail dragger, needed lots of clearance from its forward gear thanks to its extra large propellers. The big tires not only gave it the clearance it needed, but it also enabled the Me261 to use unprepared fields for takeoff and landing.

Had the Me 261 seen production, it would have been an incredible bit of serendipity for the Nazis. Assuming modest numbers were deployed by the start of 1941, it could have been used for reconnaissance flights over the Soviet Union in the buildup to Operation Barbarossa. At the same time  (assuming the Japanese would agree to its use) The Me 261 could have been used as a courier aircraft, anticipating a later Nazi project: getting strategic war materials from Japan. Given the Me 261's ability to land and take off in primitive conditions, it also would have been ideal for intelligence operations as well. Despite all this, there appears to have been quite of bit of work done on the Me 261's bomb dropping capacity, which was kinda dumb: the Me 261 was a high-flyer with a limited bomb load. Dropping small amounts of explosives from really high up was never going to set the world, or even a steel works in Novosibirsk, on fire.

An Me 261 after a landing gear collapse. You can make out the little cabin windows along the top of the fuselage.

 Fortunately for the world, this incredible bit of luck was then lost through incompetence.  When in 1939 it became clear the fourth-coming war was going to cancel the 1940 Olympics, all work on the Me 261 essentially stopped. It seems that the first prototype was near completion, but with increasing demands on Messerschmidt's productive capacity, the project was left out (metaphorically and possibly literally) behind Messerschmidt's shed. Getting a pair of DB 606s would further delay things: the first prototype would only take to the sky in December of 1940.

The other design study Messerschmitt was working on at the time eventually get the designation Me 264 - a four engine prototype of an airplane that could (maybe) attack America. Using the same philosophy of high flying/low drag design that informed the Me 261, Messerschmitt envisioned a four-engine aircraft that could fly and attack at extraordinary distances. In the name of efficiency (and a dearth of appropriate engines) the design studies were of an aircraft much smaller than the B-36, with a bomb payload that topped out at 5 or so tons. The fuselage was a long, narrow tube not much larger than the Me-264's engine nacelles - this was both to lessen drag and to make the aircraft more mass-producible. Defenses were sunken remote control turrets, like those envisioned for the He 177. Messerschmidt hoped for an operational radius of 10,000 km; or if you prefer, 20% greater than the future B-36.  Messerschmitt showed Hitler a model of what would become the Me 264 in 1937, during the Great Dictator's tour of Messerschmitt's factory. Hitler was impressed, and possibly formed an impression that these aircraft were closer to reality than they in fact were.

Like the Me 261, the Me 264 was on the back burner at Messerschmitt in the runup to and during the war's early phase. It would start to get resources as the Nazis organizations began to worry about Germany's lack of long range aircraft. The He 177 prototype had taken its first flight in 1939, but was not scheduled to go operational with KG 40 until August 1941 - and it was clear that it would not have the very long range that the German Navy (among others) wanted. As preposterous as this sounds, there was talk of what Germany would do once the war was won; the Nazis had no aircraft capable of flying to Germany's non-existent but soon to be re-acquired colonial possessions in Africa. At the same time by 1940, war with the United States loomed ever larger over the western horizon. This got the RLM thinking of the possibilities of attacking the United States directly via aircraft and supporting U-boats in the Western Atlantic from the air, ideally with some sort of guided munition attack capability.  Now that the Nazis possessed France, after all, the problem of trans-Atlantic aircraft was at least 3% easier!

There's a third design that never got as far as the prototype stage that Messerschmitt had, the P.1073A.  In some ways, it was less serious than the other two designs, as it seems to have been a stab at what kind of transocean bombers you could make under ideal, rather than Nazi, conditions. I'll talk about it in a later post, as it takes us ahead in our story.

Despite the RLM becoming curious at least what their aircraft industry to whip up in the form of a globe-spanning aircraft, RLM heads Milch and Jenschonneck remained skeptical of the "bomber of staggering magnificence" option. They also thought aerial refueling was implausible. So, initially, when considering these questions, they turned to flying boats as the easiest, most economical way to go very long range.  This was sensible in one crucial respect: in addition to the flying boats under development, one trans-Atlantic flying boat was already flying by this time.


Viking Longships

This was the Blohm und Voss (BV) 222 "Viking". As mentioned before on this blog, Lufthansa had in the mid-1930s did the Third Reich an enormous favor by developing a number of aircraft with which to secure long-range air routes with. Cleverly they hedged their technological bets, developing a number of different aircraft configurations for this role. These include the Fw 200 Condor, the adaptation of a discarded Luftwaffe bomber project into a wide-body airliner, the Ju 90, and even the development of a very large floatplane, the BV Ha 139. The BV 222 was their enormous flying boat contestant.

In the design competition for Lufthansa's big new ocean liner, Dr. Richard Voght, head of aero projects at BV, made an extremely savvy move in BV's entry: rather than specify four modern engines, he spec'd instead six older ones. With the aircraft engine crunch a very real thing even in prewar Nazi Germany, this move meant that the Viking would actually be able to get, well, engines, without having to endlessly nag the RLM to release some aero engines already earmarked for military applications. Lufthansa awarded Blohm und Voss the contract in 1937, with the first flight of the BnV 222 happening on the 7th of September, 1940.

It is all but forgotten now, but Nazi mobiles were *insane*.
One of the first two Bv 222s in flight tests.

I seem to spend, all things considered, an inordinate amount of time on this blog saying "holy shit, was it ever big." This is true of the Viking - but as a statement, "holy shit, it was big" isn't much fun if it has to be closely qualified to be accurate. The BV 222 was the largest production aircraft to see combat in the Second World War. This statement is true, but has to stand among several awkward facts:

1. It was not the largest aircraft the Germans developed; that would be the prototype BV 238;

2. It is arguable that it was, in fact, the largest, as the Me 323 improvised transport was larger in several dimensions;

3.  writers will try to get around all of this by describing the BV 222 as the largest combat aircraft. That's debatable as well; it was armed, but only defensively.

4. it was by no means the largest aircraft of the Second World War. That goes to the all-time ruiner of big aircraft comparisons, the Hughes H300 Hercules flying boat, also known as the "Spruce Goose." While the prototype flew only once after World War 2, it remains one of the largest aircraft ever built, even today, and still has the greatest all time wingspan of any aircraft.

All that said, the BV 222 was larger than several things, with some impressive design features. It had a double deck, like most large flying boats,  with large hatches along the sides, so cargo could roll right off the dock onto the Viking's lower deck. The fuselage was about as long as an actual Viking longship, and had a similar cargo capacity, except, y'know, it could fly? It had a  wingspan of 46 meters, (about 150 ft) and a length of 37 m (127 ft.) It was 10 m (35 ft) high. It's close in size to the postwar American flying boat, the Martin Mars, though the Mars' superior engines (Wright 3330 radials, the same engine on the B-29) gave a vastly greater take-off weight (74,000 kg vs 49,000 kg.).

A Bv 222 captured by the British at the end of World War 2. White paint is an attempt at arctic camouflage.

Two shots of a later Bv 220s, with diesel engines and outfitted for the FuG 200 search radar.

I'm sorry the Viking is so small and unimpressive.

The initial 7 aircraft used Brembo 323 radials with an output of 1000 hp each, the same engine as the Fw 200, while aircraft after that used diesel Jumo 207Cs, which had the same power output but a better fuel consumption. In its patrol guise, the BnV 222 had an astonishing endurance for something so large medium sized: 6000 km, being able to stay aloft for 28 hours. The Jumo 207 also allowed a Viking to refuel from the fuel tanks of a U-boat, which was one of those features that made Nazis smile like children on Christmas Eve.


Here is a video of the BV 222 undergoing flight testing,
 if you need moving images to understand bigness.

The BV 222 wasn't quite a Christmas miracle, though - this Viking was large, but mostly made out of paper mache. Despite being developed in Nazi Germany in the late 1930s, no thought had been given to making the Viking a combat flyer. The Nazis drafted it for war basically because it was big and it could fly long distances. It was also a civilian in another, crucial way: it was being built in a civilian factory in Hamburg. Making it into a more viable military air-frame would mean finding resources to expanding the factory and spoiler alert: this doesn't happen. It seems somebody in the RLM anticipated the problems of drafting this civilian, and in February 1940 Blohm und Voss was commissioned to build a military flying boat with capabilities exceeding the BnV 222's. In addition to bombing and naval recon, the new flying boat was envisioned as being ideal for the delivery of German troops and supplies to [nonexistent] German colonies. There was also some talk of flying boats being ideal for deploying colonial Nazi marines deployed by massive flying boat as a fast reaction force. This new project would turn into the BV 238 - the other notable huge [fairly big, I mean, pretty big] Nazi flying boat, as it existed as a prototype.

The first two shots are from inside the Bv 222's wing - as with many big aircraft of the day, engineers made provisions for the engines to be serviceable while in flight. The firewall opens to give engine access. 



The wing pontoons were retractable. 


The cargo deck of the Viking. 
 Nonexistent flying boats of the Third Reich

The civilian aviation ambitions of the German aviation industry had seen many large flying boat projects started. The most important of these was the Dornier 214, as it was close to having a prototype constructed, if not ready to enter series production.

An illustration from a old Monogram reference on the Do 335.



Like the BV 222, it would be an out-sized, twin deck luxurious flying boat on a trans-Atlantic route, in this case, a direct flight from Lisbon to New York. The Do 214, however, was considerably larger, to the point I might've been able to say "holy shit it was big" without qualification. It was to have eight engines instead of six, for starters, and those engines were to be modern, next generation aircraft engines making at least 2000 hp, with the best powerplant being the DB 613: two V12s linked together to make a 24 cylinder, 4000 hp monster of an aircraft engine.  If you imagine a flying boat version of the B-36 (which was a proposed variant, believe it or not), or maybe a militarized Saunders-Roe Princess, you are getting the drift of the Do 214. Vital stats were a wingspan of 60 m (197 ft) and a B-36-like length of 51 meters, or 169 ft. It's max takeoff weight would have been a very ship-like 145,000 kg, or 319,000 lbs - not a lot less than the B-36's statistics.

An illustration of the Do 214 from
from the excellent book Luftwaffe Secret Projects Vol. 3:Strategic Bombers.


I took this one to my weekly coloring chill-out session.

 The civilian model was re-imagined for war work once it kicked off in 1939. In addition to more prosaic scouting and attack missions, Dornier really put in some extra time imagining other possible uses for the Do 214. The most interesting of these was U-boat resupply. As a giant flying milch cow, the Do 214 could have filled a handy little niche for the Kriegsmarine. It was also pitched as a flying tanker aircraft (it's possible this was aerial refueling, but given the time I think Dornier was thinking of refueling ships), a troop transport capable of carrying 333 personnel, a cargo transport capable of lifting 82,000 kg (180,000 lbs, or 90 tons), a flying ambulance (or clinic, whatev), or a long range heavy bomber that would use guided weapons for ship attacks. This was no mere fishing expedition on the part of Dornier, who had built a 1/5th prototype aircraft to test the hull shape, and also did extensive wind tunnel testing with a model that is in Dornier's museum today.

There were two other notable projects going on at the time. Focke Wulf had advanced the field of airliners with the introduction of the Fw 200; it was now naturally looking to follow up on that success with a larger aircraft. From 1937 to 1940, Focke-Wulf did many design studies which they called the transocean project. Imagined as a direct flying passenger or cargo plane, Focke-Wulf imagined direct from Germany to America as a excellent performance goal. While none of these would see the light of day, they formed the background to several later bomber projects. The other notable was the Junkers EF100. Like Focke-Wulf, Junkers had scored a success with the Ju 90 airliner, and was dreaming of what a post-war airliner would look like. The EF100 used 4-6 Jumo diesel engines to (hopefully) achieve its target performance: hauling a 20,000 kg payload 9000 km. The RLM at some point got the project modified to become a long distance maritime reconnaissance plane - but then the project was shelved near the end of 1940, as the RLM thought flying boats offered better possibilities.

A militarized EF 100.

 The weakness of these paper projects is obvious in hindsight: engines. The ability of the aircraft to accomplish what it said on the tin they came in was dependent on what kind of engines could be sourced for them. Aircraft Designers naturally assumed that engines would be around in a few years time that would at least be in the ballpark of what was imagined. When those engines were delayed more or less indefinitely, that usually spelled doom for the design as well.

Summary

So by the end of 1940, the Nazis were fishing about for ideas about attacking America from the air. Even at this early juncture, there were two different ideas floating around. The first was to make a bespoke Amerika bomber; the second was a whole rolling series of ideas about how to attack America at least once without constructing an bespoke airframe. There were also two distinct trains of thought leaving the station as to what the goal was: one saw raids on America as psychological, to damage enemy morale. The other saw it as a rational way to damage (slightly) North American industrial output. While there was hope some actual factories might be exploded, damage here is the enemy using resources to defend against occasional raids by German super-vultures. This sort of muddled thinking is completely natural when people are floating ideas, but, this ambiguity would never actually be excised from the RLM's thought processes. Good thing this is just a bunch of people talking!

And it was, until 1941.

Part of the Amerika Bomber series. 

Part 1: Black Gay Hitler

 Part 3: Walkin' on Sunshine

Part 4: Stuffing arrogant mouths 

Part 5: Eris is Goddess

Part 6: Ragnarocky Road

Part 6: Ragnarocky Road

Part 7: Look Busy and Hope Americans Capture You

Part 8: Rocket-Powered Daydream Death Notes 

Appendix: A4 Guidance  

Wednesday 8 February 2017

A Note on Engines

The Germans in some ways did very well with aircraft engines in the Second World War. Despite having less aero engine experience than the  British and Americans, they none the less managed to stay at rough parity with the Allies through the Second World War, with the Jumo 213 and the BMW 801 seeing constant development until war's end. The use of fuel injection rather than carburetors was an advancement over Allied designs, and the use of methanol as an aviation fuel additive was a clever fix to poor quality Axis fuel. At the same time, aero engines were yet another area where Germany was at a material disadvantage. The engines with the greatest performance couldn't be produced in anything like the numbers demanded, and metallurgy - especially in the creation of turbo and superchargers - was something that Germany's limited access to rarer metals couldn't help but suffer from. Both types of chargers cram extra air into engine cylinders to increase combustion, or at high altitudes increase the amount of air in a cylinder to stop power loss. Turbochargers are a turbine driven by exhaust gasses to create compression, while superchargers compress air via an engine driven by power off of the motor. Both have to work very close to the point of combustion, and thus experience *extremely* high temperatures; thus constructing working versions of a charger requires tight metallurgy skillz.

Until turbines arrive on the scene, aircraft engines came in two flavors: liquid-cooled and air-cooled radial. Liquid cooled aircraft engines are quite similar in mechanics to engines in cars today: they use liquid to manage waste heat. The performance was slightly better than a radial, but it came with a drawback that engine damage might cause the coolant to bleed out and render the engine (and often the airplane) nonfunctional. The radial was a series of pistons firing around a central crankshaft. While they gave away some raw output of liquid cooling they had a few advantages to the aircraft designer: first, they cooled themselves by air, and were thus could be lighter than a comparative liquid cooled V12. The air cooled aspect also made them less vulnerable to damage, as no vulnerable cooling fluid could leak away. Beyond that, radials sometimes took fairly incredible trauma and kept operating; radials could have their pistons shot off and still function, abet with a higher oil consumption.

All the combatants in the Second World War spent a lot of time and money trying to develop new engines. With Germany the evolution of existing designs happened kept pace, introducing new high powered piston engines went poorly. Several engines were scheduled to appear that would have the output for heavy, large aircraft just didn't, with many designs finding themselves canceled once the engine designers had based their projections on turned out to be vaporware.

This is especially important in the Nazi Amerika bomber projects, as the whole endeavor was impossible without engines of a very high level of reliability, power output, and power to ratio weight. The B-36 and the famous Hughes 300, the 'Spruce Goose', used six and eight Wasp majors, radial monster engines with an output that started at 2500 hp. America and Britain, despite their advantages, struggled in getting engines that past the 2000 hp mark - as a matter of fact, the Wasp Major and its supporting act in the monsters of internal combustion tour, the Wright R-3330, had delays and technical problems galore during World War 2. The Allies did manage to break the 2000 hp barrier - the slightly, lovably, mad British Napier H-24 could put out 2400 hp at low altitudes in 1944 - but this was not without a significant investment of blood, sweat, and tears.

My point is that the Nazis never had large engines that could manage this output - hence the linked engines debacle of the He 177. When looking at hypothetical Nazi Aircraft, one can gauge its plausibility simply by looking at the projected engine output - generally, anything above 2000 hp should be viewed as unlikely, especially as such an engine would have enormous pressure to go into a defensive fighter mid-1943 onward, assuming a minimal level of Black Gay Hitler. If those outputs stretch to the 3000 hp or above, our Black Gay Hitler curve approaches its Liberace point since we're now assuming a world where Jumo could develop and deploy Wasp Major-like engines successfully because the Third Reich defeated the Soviet Union and now rules everything west of the A-A line.
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