Engine quastion about He-177

[pressurized]

The whole reason behind the coupled engines was to allow the aircraft to be perform Dive Bombing duties.

Wrong my friend. Siegfried Gunter used the coupled configuration to reduce frontal area and therby reduce overall drag. He felt that the combination of four engines driving two propellers would result in greatly improved performance. The RLM shortsidedly added the dive bombing role only after the initial design was conceived, thereby adding weight and complexity to the design. The crippling problem of engine fires was mainly caused by the close proximity of the two engines, and was exacerbated by the fact that the external oil cooler lines were run between the two cylinder blocks. The added heat did not help, but when a line ruptured,the fire was usually catastrophic.

 

[FLYBOYJ]

Wrong my friend. Siegfried Gunter used the coupled configuration to reduce frontal area and therby reduce overall drag. He felt that the combination of four engines driving two propellers would result in greatly improved performance. The RLM shortsidedly added the dive bombing role only after the initial design was conceived, thereby adding weight and complexity to the design. The crippling problem of engine fires was mainly caused by the close proximity of the two engines, and was exacerbated by the fact that the external oil cooler lines were run between the two cylinder blocks. The added heat did not help, but when a line ruptured,the fire was usually catastrophic.

From Wiki with a reference...

The mock-up was completed in November 1937, and on November 5, 1937 allocated the official RLM type number "8-177", the same day that the OKL first stipulated the requirement for the new design to possess sufficient structural strength to enable it to undertake medium degree diving attacks.

Griehl Dressel 1998, pg.9

 

[krieghund]

Actually, the DB610 - 613 series was not a bad engine as they were based on two established proven engines it was a quick way of getting a larger capacity engine without resorting to extensive engineering as in the Wright R-3350 (Its history is jaded just as the DB610 installation in the He177)

The bad reputation of the DB610 comes from the installation not the engine. biggest problem was the routing of the lubrication lines/system and NO FIRE WALL!!!!!! Of course stressing it for dive bombing added undue weight to the structure.

One He177A5 was taken by the RLM and 57 engineering fixes applied to it resulting in a reliable engine installation, however, the production line was too far along to incorporate these and only a few got applied but it still improved reliability.....the RAF's captured model gave them no troubles in testing/evaluating

The installation was to knock a few digits of of the coef. of drag CDo I have these figures and will post them when I return home from vacation

 

[DerAdlerIstGelandet]

Wrong my friend. Siegfried Gunter used the coupled configuration to reduce frontal area and therby reduce overall drag. He felt that the combination of four engines driving two propellers would result in greatly improved performance. The RLM shortsidedly added the dive bombing role only after the initial design was conceived, thereby adding weight and complexity to the design. The crippling problem of engine fires was mainly caused by the close proximity of the two engines, and was exacerbated by the fact that the external oil cooler lines were run between the two cylinder blocks. The added heat did not help, but when a line ruptured,the fire was usually catastrophic.

Then please explain to me why every source (book whatever you name it) backs up what I stated.

 

[The PIPE]

Dear Rousseau and Other "Grauerliche-Greif" Fans:

The PIPE Here...and over the years, I've become quite a "student" of the virtually COMPLETE failure of the Third Reich to have a truly usable heavy bomber for their Luftwaffe, for most of World War II.

The initial Dornier Do 19 and Junkers Ju 89 "Ural-Bomber" prototypes WERE good attempts in the late 1930s, when the Luftwaffe's only serious proponent of strategic bombing, General Walter Wever, lost his life in a crash of a Heinkel He 70 on takeoff. That event occurred less than a year after the initial prototype for the B-17 crashed for the very same reason, when both aircrafts' "gust locks" on their control surfaces were never disengaged/removed before their final takeoffs.

Ernst Heinkel did, at least, TRY to have what could have been a decent design for a heavy bomber, but on the very day...November 5, 1937...that the RLM issued the airframe type humber "8-177" for Herr Heinkel's heavy bomber design, that the "Stuka dummkopfen" (my own name for them!) in the RLM HAD to insist that the new "He 177" design HAD to be capable of 45º diving attacks, which was something that Heinkel opposed vehemently from the very beginning. and condemned his "heavy" to being a trouble-prone aircraft from then on, from ALMOST all of the complications of that demand for diving attacks, except for Siegfried Günther's initial idea of using the twinned-up quartet of DB 601s as a pair of DB 606 "power system" engines.

All the while, amazingly enough until the late summer of 1942, Fat Hermann HAD thought that the He 177A WAS a truly four engined heavy bomber...and when he had found out about the "power system" format, twinned-up DB 601 pairs of engines (as the DB 606, of course) in each of the 177A's two nacelles, he IMMEDIATELY deemed them to be "welded-together engines", and demanded that a full-blown "truly four engined" new version of the He 177 be created that DID abandon the "coupled" engine format of the A-series. By September of 1942, Goering had not only rescinded the diving attack demands of the "Stuka-dummkopfen" at the RLM, but Heinkel had started the design of what was ALWAYS called the He 177B, using four independent DB 603 powerplants, with each one residing behind the very same annular radiator that his firm had already created for that firm's Heinkel He 219 night fighter.

The He 177B program, in reality, was never, never, NEVER used as a "cover designation" for ANYTHING else Heinkel was designing...the other two attempts of the Heinkel firm to create a four-engined strategic bomber, the He 274 (two prototypes built and flown), and the paper-ONLY He 277, which was going to have a much-enlarged He 219 prototype-style side-view profile fuselage, which never had anything built for IT other than a few parts, resulted in no flyable prototypes during the war years. The He 177B program, by contrast, resulted in four prototypes being commissioned, the He 177 V101 to V104, of which the first pair of airframes were converted from A-series airframes already in existence, and which managed to fly later in 1943.

Heinkel was basically, by matters of circumstance, attempting to do what Roy Chadwick had ALREADY done with the seriously deficient Avro Manchester in comverting IT into the all-conquering Lancaster heavy bomber...but Heinkel wasn't allowed to do it, by creating the Berta-series He 177B, until some 30-plus moths after Chadwick had given the Manchester a quartet of smooth-running Merlins, and a bit more wingspan, in creating the Lancaster.

Thanks to the "Stuka-Dummkopfen", though, Herr Heinkel HAD to endure all those problems with the He 177A for three-years-PLUS until Goering woke up and smelled the kaffee, when he declared the DB 606 (AND the 610s, of course) as those "misbegotten monsters of welded-together engines" by the end of the summer of 1942, just when the Luftwaffe COULD have used a truly four-engined heavy !!!

That Manfred Griehl-Joachim Dressel authored book on the Gruesome Griffin is SUCH a great source of how things "REALLY happened" regarding the truly four-engined He 177s...if anyone's got that great book take a look at it CAREFULLY as to how it regards the He 177B-vs-He 277 controversy, and "explodes" the whole urban legend on the "He 177B" only being a "cover designation" for the "He 277", an aircraft that was NEVER completed and flown at ANY time...!!!

Yours Sincerely,

The PIPE!

 

[red admiral]

Heinkel was basically, by matters of circumstance, attempting to do what Roy Chadwick had ALREADY done with the seriously deficient Avro Manchester in comverting IT into the all-conquering Lancaster heavy bomber...but Heinkel wasn't allowed to do it, by creating the Berta-series He 177B, until some 30-plus moths after Chadwick had given the Manchester a quartet of smooth-running Merlins, and a bit more wingspan, in creating the Lancaster.

The Manchester-Lancaster doesn't really transfer over to the He 177 series. In moving from two Vultures to four Merlins there was a massive power increase. 2x1750hp to 4x1280hp (and later 1640hp) is a jump in power of almost 50%, with consequent effect on performance, even with the larger Lancaster wing.

The He 177 engine arrangement results in very little difference in power whether the engines are coupled together or not. With four engine nacelles containing DB 601/5s there's about the same power as before, but more drag, even without a larger wing. Peformance is going to decrease, not increase. Probably still good enough with more reliable DB601/5s, but numbers is always going to be a problem.

 

[Njaco]

All the while, amazingly enough until the late summer of 1942, Fat Hermann HAD thought that the He 177A WAS a truly four engined heavy bomber...and when he had found out about the "power system" format, twinned-up DB 601 pairs of engines (as the DB 606, of course) in each of the 177A's two nacelles, he IMMEDIATELY deemed them to be "welded-together engines", and demanded that a full-blown "truly four engined" new version of the He 177 be created that DID abandon the "coupled" engine format of the A-series. By September of 1942, Goering had not only rescinded the diving attack demands of the "Stuka-dummkopfen" at the RLM, but Heinkel had started the design of what was ALWAYS called the He 177B, using four independent DB 603 powerplants, with each one residing behind the very same annular radiator that his firm had already created for that firm's Heinkel He 219 night fighter.

After soo many books and material, that is the first time that I've heard Goering demand the He-177 be changed. I've always read that Heinkel badgered Goering so bad with a true 4 eng design that he finally forbade Heinkel from making it.

Where in the book is this new tidbit?

 

[DerAdlerIstGelandet]

I am still waiting to find out how my information above was wrong?

 

[The PIPE]

Dear DerAdleristGelandet Njaco:

The PIPE Here again...it's at page 53 of the Griehl-Dressel book on the Gruesome Griffin that the mention of ol'Fat Hermann THINKING that the Griffin WAS actually a "seperately engined" four-engined heavy, with the folliwing text in the book...I quote:

"In the meantime, new reports had given Reichsmarschall Goering another scare; for it seems that until summer 1942 he had believed the He 177 to be a four-engined aircraft, and one capable of diving attacks at that:

"I had told Udet from the start that I wanted this beast with four engines. This crate must have had four engines at some time! Nobody had told me anything about this hocus-pocus with welded-together engines."

The following text at the Wikipedia page regarding the so-called "The "He 177B" versus He 277 controversy", entirely authored by myself and tottally based on the solid evidence in the Griehl/Dressel book, confirmed the actual situation that existed reagarding the He 177B as an actual aircraft, and the "He 277" strictly being a paper-ONLY project...again, I quote (but this time these ARE my own words, no kidding!)...

"For many years after the war, a substantial number of aviation history books and magazine articles that dealt with late World War II German military aviation developments consistently stated that Reichsmarschall Hermann Goering, early in World War II, was becoming so frustrated by the 177A's ongoing engine problems, caused by the twin DB 606 "coupled" powerplants selected for the He 177A design in the pre-war years, that he forbade Ernst Heinkel from doing any work on a separately four-engined version of the 177 airframe, or even mentioning a new "He 277" design with four separate engines, until Heinkel brought the disagreement directly to Adolf Hitler, who supposedly not only approved of calling the new, separately engined version of the 177 the "He 277", but overruled Goering's prohibition on working on the design, previously called the "He 177B" by Heinkel as a "cover designation" to hide its existence from Goering, and the RLM, to bring it into production.

Statements by Goering himself in August of 1942, however, seem to directly contradict elements of the oft-repeated story, as those statements seem to show that Goering thought that the He 177A actually had four separate engines, and derisively labeled the coupled engine arrangements as "welded-together engines" [from pgs 52 53 of the Griehl/Dressel book], in his complaints about the He 177A's ongoing engine difficulties, and was anxious to see a truly four-engined version of Heinkel's heavy bomber fully developed and in production.

One fact that could have fostered the origin of the post-war aviation book storyline about the "He 177B"/He 277 controversy was that the RLM, in listing the He 177 development projects that they approved of the Heinkel firm doing work on as of February 1943 (six months after Goering's recorded engine complaint statements), only included the He 177 A-5 heavy bomber, A-6 high-altitude bomber, A-7 long-range version, and the "He 277" itself.[from pg. 179]

The main factor that seemingly required the lower-drag "coupled" powerplant format for the He 177A, the diving attack mandate by the RLM, which Heinkel himself vehemently disagreed with, was rescinded by Goering himself some five months before the "He 277"'s February 1943 RLM approval date, [pg. 53] and Heinkel started work on the He 177B as a straightforward, separately four-engined development of the 177A under the B-series designation at least as early as the late summer of 1943, when official Heinkel documents began referring to the He 177B as a fully RLM approved development of the original He 177 aircraft line, [pg.161] and not in any way directly related to the entirely separate He 277 advanced bomber design project.

In total, there were three separate efforts to develop "true four-engined versions" of the A-series Greif: the He 177B, which culminated in four prototype examples being built, with three getting airborne before the war's end; the He 274, of which only two prototypes were started before the end of World War II and completed and flown in France after the war's end; and the He 277, which only had a few airframe parts in the process of completion and no completed prototypes at any time, before or after the war."

And in the section in the Wikipedia's He 177 section, entitled "Further Development-The He 177B Prototypes", here the folliwing text, again mostly my own work from info in the Griehl/Dressel book...

"Due to continuing problems with the DB 606's configuration, much development work was being done in order to rectify engine complications, including a complete redesign of the original He 177 intended towards the creation of a four engined version of the Greif's airframe. Ernst Udet was critical of the coupled DB 606 powerplant for the He 177 from before the war's start, with Goering adding his input from his own frustrations with the seemingly interminable engine problems delaying the introduction of He 177 into service. Goering was reported as stating in August 1942:

" I had told Udet from the start that I wanted this beast with four engines. This crate must have had four engines at some time! Nobody had told me anything about this hocus-pocus with welded-together engines."

The RLM's requirement for the He 177 to perform diving attacks was finally rescinded in September 1942 by Goering himself, and with that decision finally rendered, Heinkel's design work on four engined versions of the He 177A, collectively named the He 177B, were then able to progress, all to be powered with four individual Daimler-Benz DB 603 engines, with each liquid-cooled DB 603 fitted with a Heinkel He 219-style annular radiator right behind the propeller for engine cooling. This task was accomplished in a considerably later timeframe than British aircraft designer Roy Chadwick had done in similarly converting the Avro Manchester. The initial design of the Manchester, like the A-series Greif with its coupled DB 606s and 610s, had similarly depended on only two very powerful and quite troublesome 24-cylinder powerplants, the British Rolls-Royce Vulture, which by 1941 had evolved under Chadwick's work into the Rolls-Royce Merlin powered, truly four-engined Avro Lancaster. By August 1943 much of the detail work for the He 177B series aircraft was well on its way to completion, and Erhard Milch approved the creation[pg. 162] of three He 177B prototypes, designated He 177 V101 to V103. The V101 was converted from a mid-production He 177 A-3 airframe (number 535550, with Stammkennzeichen of NN + QQ), the V102 being converted from the eighth He 177 A-0 production prototype aircraft, and the V103 being converted from an existing, early production He 177 A-5 airframe. The V102 was the first to be fitted with an empennage of twin tail configuration that, when tested, gave the V102 significantly better in-flight handling when compared to the original He 177A's single tail design, except during the landing approach when the fowler flaps were extended, when flown in November 1943.[pg. 163] The only photograph that exists today of any of these He 177B prototypes is one of the V101, parked outdoors on a foggy German airfield.

The He 177B was also intended to introduce a slightly enlarged, somewhat more aerodynamic fully-glazed nose [pg.152] that could incorporate a remotely controlled power chin turret for forward ventral defense, mounting either a pair of MG 131 machine guns or MG 151 cannon, but the nose was only tested on the fifteenth He 177 A-0 production prototype, without the chin turret, and was never fitted on any of the He 177B prototypes, which used the standard "Cabin 3" He 177A's well-framed nose. No photographs of this new nose design are known to have survived the war and only drawings exist of it in modern archives. The remaining defensive armament generally remained similar to the He 177A, particularly the twin dorsal gun turrets for the He 177 B-5, with the aft manned dorsal turret being deleted on the planned He 177 B-7 (as on the He 177 A-7) to reduce weight, and a fully powered manned Hecklafette HL 131V tail turret, carrying a quartet of MG 131 machine guns, was intended for installation on the prototypes and would have been standardized on the production aircraft, but never went beyond the mockup and working prototype stage.

The first flights of the He 177B prototypes occurred between late December 1943 and early January 1944 in the vicinity of the Vienna-Schwechat airfield, at Heinkel's southern production facility, where an additional prototype, the V104, whose purpose was to be the "finalized" production prototype for the He 177 B-5, was being completed by order from the RLM, converted from an early production He 177 A-5.

However, from late April through July 1944, repeated Fifteenth Air Force bombing raids on German aircraft production facilities in Vienna destroyed the airworthy V103 and the incomplete V104, setting back any plans of producing He 177 B-5. The adoption of the Emergency Fighter Program dealt the final blow to the entire He 177B development program, with the Heinkel He 162 jet fighter being the only new Heinkel aircraft design that would be allowed into production."

So, "there you have it"...the He 277 was NEVER completed past a few parts, but there WERE...FOUR...He 177B prototype aircraft approved, and the first three of those were built and FLOWN...and NONE, of those aircraft EVER bore the "He 277" monicker at any time, FOR REAL, which is what the post-war aviation book "urban legend" WOULD have us believing...and I'm very glad to have a copy of it.

Thank You and Yours Sincerely,

The PIPE...!

 

[Njaco]

So, "there you have it"...the He 277 was NEVER completed past a few parts, but there WERE...FOUR...He 177B prototype aircraft approved, and the first three of those were built and FLOWN...and NONE, of those aircraft EVER bore the "He 277" monicker at any time, FOR REAL, which is what the post-war aviation book "urban legend" WOULD have us believing...and I'm very glad to have a copy of it.

Since we're working with single sources, R.S. Hirsch and Uwe Feist in "He 177" state; "Actually the first four seperate engined 177 aircraft flight test started late in 1943 in Vienna. A standard He 177A-3/R2 was modified and became the 277 V-1. It was referred to in official correspondance as the He 177 B-0. The second prototype He 177 V-2, referred to in correspondance from Heinkel to the RLM as the He 277 B-5/R1 was converted from a standard He 177 A-5/ R8. The V-2 was flown to Rechlin for extensive trials. The He 277 V-3 was similar to the V-2 except a new tail assembly with twin rudders was fitted. This produced highly satisfactory results eliminating all directional instability characteristics of the V-1 and V-2. The production model was designated He 277 B-5/ R2 wiping clean the old designation He 177 B-5 / R2. Goering held a conference on May 25th, 1944 and ordered 200 machines a month. Quanity production started immediately until on the 3rd of July 1944, the whole bomber program was scrapped to give top priority to fighters....The He 277 B-7 was projected as a long-range reconnaissance aircraft and was derived from the He 177 A-7....Only one was completed and this had DB 603A engines. It was destroyed along with eight He 277 B-5's before Russian troops entered the area...."

Thats just one source. Seems like there were more than 4, they were called He 277s and unless you have those correspondance from Heinkel to the RLM (which I don't) I would'nt be so sure that everything is set in concrete. Especially with a single book reference.

 

[DerAdlerIstGelandet]

I am not talking a He 277 here. I am still talking about the He 177, and no matter what Goerring thought, does not change why the He 177 had coupled engines. So again my question still stands.

 

[Propellorhead]

Wrong my friend. Siegfried Gunter used the coupled configuration to reduce frontal area and therby reduce overall drag. He felt that the combination of four engines driving two propellers would result in greatly improved performance. The RLM shortsidedly added the dive bombing role only after the initial design was conceived, thereby adding weight and complexity to the design. The crippling problem of engine fires was mainly caused by the close proximity of the two engines, and was exacerbated by the fact that the external oil cooler lines were run between the two cylinder blocks. The added heat did not help, but when a line ruptured,the fire was usually catastrophic.

Nope sorry but the same day that RLM awarded the "8-177" designation, Luftwaffe high Command also stipulated that it be capable of medium dive bombing. It was also built to the Ural bomber specification of 1000kg payload over 5,000km at no less than 500 km per hour cruise speed. This last factor determined the need for at least 2000hp per propeller and obliged the double tandem engine layout owing to the lack of suitably powerful engines in 1938/39.

There was also a blowback issue with engines which forced oil to pool in a shared exhaust manifold.

 

[Propellorhead]

Dear DerAdleristGelandet Njaco:

The PIPE Here again...it's at page 53 of the Griehl-Dressel book on the Gruesome Griffin that the mention of ol'Fat Hermann THINKING that the Griffin WAS actually a "seperately engined" four-engined heavy, with the folliwing text in the book...

The first flights of the He 177B prototypes occurred between late December 1943 and early January 1944 in the vicinity of the Vienna-Schwechat airfield, at Heinkel's southern production facility, where an additional prototype, the V104, whose purpose was to be the "finalized" production prototype for the He 177 B-5, was being completed by order from the RLM, converted from an early production He 177 A-5.

However, from late April through July 1944, repeated Fifteenth Air Force bombing raids on German aircraft production facilities in Vienna destroyed the airworthy V103 and the incomplete V104, setting back any plans of producing He 177 B-5. The adoption of the Emergency Fighter Program dealt the final blow to the entire He 177B development program, with the Heinkel He 162 jet fighter being the only new Heinkel aircraft design that would be allowed into production."[/COLOR][/SIZE]

So, "there you have it"...the He 277 was NEVER completed past a few parts, but there WERE...FOUR...He 177B prototype aircraft approved, and the first three of those were built and FLOWN...and NONE, of those aircraft EVER bore the "He 277" monicker at any time, FOR REAL, which is what the post-war aviation book "urban legend" WOULD have us believing...and I'm very glad to have a copy of it.

Thank You and Yours Sincerely,

The PIPE...!

Wrong Pipe.

The He-177 B-0 was a separate aircraft never designed for high altitude flight as was the He-277.

The He-277 was prior to August 1943 designated as the He-177 A-8. The He-177 B-0 designation had been in existence years before this.

RLM asked Heinkel to prepare four H-177 B aircraft in late November 1938 as an insurance policy against failure of the tandem DB606 engine from the he-177A. RLM specified the He-177B to be fitted with four Jumo 211 engines each comparable to a DB601 in power.

The He177 B V101 was found burned out at Cheb in May 1945. It was fitted with the Jumo 222 when destroyed, thus it was not the high altitude He-277 B-5 aircraft powered by the high altitude Jumo 213E. Nor was the He-177 B V101 found at Cheb fitted with a pressurised cockpit thus it was not the He-277 at all.

The He-277 had it's own V number range up to V26 and these aircraft were manufactured at Vienna from December 1943 to 2 July 1944. Two He-177 B-0 were converted to He-227 B-5 and these two aircraft were destroyed at Vienna.

 

[Konig]

My thoughts...

The 177 was a product of total mismanagement and confusion over the roles it had to perform. I think if they had defined the roles of this bomber at the outset and left the designers alone, the aircraft would have been fairly successful. As it was the roles of the this aircraft were changed many times during it's design and flight test stage. Heavy bomber to dive bomber , to maritime strike aircraft to launch platform....In short the aircraft had an identify crisis that was to prove it's undoing.

The he277 was a much more successful design as it had one prescribed role....a heavy bomber...The Luftwaffe had a myriad of dive bomber/maritime patrol aircraft that performed their jobs well...why not leave it at that. The one thing the Luftwaffe did not have was a conventional long range heavy bomber....it shows an incredible lack of foresight on behalf of the politicians who stuffed the he-177 up in it's infancy. The protracted war in Russia and the allied heavy bomber offensive on Germany later in the war sealed it's fate.

Given the pressures of the war and need to produce an aircraft quickly, the coupled engine idea or remote gun turrets idea or any other nonconventional aircraft designs were such a waste of material, time and effort.

I also think that Milch in particular was too much the business man. Always trying to squeeze too much out of one airframe for different roles. He killed the he-219 (role specific night fighter) project in favor of the Ju-88 for example when the 219 was clearly the better aircraft for that specific role.

Conclusion...define it's role...(heavy bomber)....leave the designers alone...stick to the conventional and oh yes...stick 4 conventional engines into 4 separate nacelles and the 177 would have been a good aircraft.

 

[Konig]

My thoughts...

The 177 was a product of total mismanagement and confusion over the roles it had to perform. I think if they had defined the roles of this bomber at the outset and left the designers alone, the aircraft would have been fairly successful. As it was the roles of the this aircraft were changed many times during it's design and flight test stage. Heavy bomber to dive bomber , to maritime strike aircraft to launch platform....In short the aircraft had an identify crisis that was to prove it's undoing.

The he277 was a much more successful design as it had one prescribed role....a heavy bomber...The Luftwaffe had a myriad of dive bomber/maritime patrol aircraft that performed their jobs well...why not leave it at that. The one thing the Luftwaffe did not have was a conventional long range heavy bomber....it shows an incredible lack of foresight on behalf of the politicians who stuffed the he-177 up in it's infancy. The protracted war in Russia and the allied heavy bomber offensive on Germany later in the war sealed it's fate.

Given the pressures of the war and need to produce an aircraft quickly, the coupled engine idea or remote gun turrets idea or any other nonconventional aircraft designs were such a waste of material, time and effort.

I also think that Milch in particular was too much the business man. Always trying to squeeze too much out of one airframe for different roles. He killed the he-219 (role specific night fighter) project in favor of the Ju-88 for example when the 219 was clearly the better aircraft for that specific role.

Conclusion...define it's role...(heavy bomber)....leave the designers alone...stick to the conventional and oh yes...stick 4 conventional engines into 4 separate nacelles and the 177 would have been a good aircraft.

 

[Propellorhead]

The He-277 was the aircraft which Heinkel probably wanted to build all along.

Heinkel was opposed bitterly by Goering arising from Goeing's accute embarassment over early failures with the He-177A. The He-177A's problems were not merely with it's DB606 engines, but also flutter and longitudinal instability for early prototypes. Instability was never truely rectified until the airframe was lengthened in the He-177 A-3.

Unfortunately there was bitter irony in Goering's hostility as it was OKL's design requirements which caused most of the problems.

Goering's ego was the biggest obstacle to Heinkel developing a true strategic bomber and it was truely strategic, both in range and altitude capability. With it's altitude ability it could fly about 16,000ft higher than the B-29 and no Allied fighter could intercept it.

The He-277 was conveniently easy to convert from early He-177 A airframes. The tail empennage appears to have borrowed from the Ju-290 and I would not be surprised if this were so. Also the pressurised cockpit was also undobtedly the same as the cockpit developed at Prague Rusnye for three He-177 A7 aircraft including V38 apparently for a nuclear bomber role.

This also highlights the question was there a shared purpose with the V38 conversion (which predates the He-277 development)

I suspect there was almost a standard conversion kit developed for converting He-177 A-3/5 airframes to He-277 B-5. If Milch wanted to develop a stategic bomber fleet in the shortest possible time with scant resources this would be the logical approach and could have resulted in very high production numbers early in 1944. The V numbers for He-277 appear to run quite high to about V26.

 

[davebender]

RLM asked Heinkel to prepare four H-177 B aircraft in late November 1938 as an insurance policy against failure of the tandem DB606 engine from the he-177A. RLM specified the He-177B to be fitted with four Jumo 211 engines each comparable to a DB601 in power.

If true then why didn't RLM just continue funding Ju-89 / Ju-90 / Ju-290 development? The Ju-90 was powered by 4 x 820 hp BMW132 radial engines. Replace them with 4 x 1,200 hp Jumo211 V12 engines and you've got a decent heavy bomber ready for mass production by 1940.

 

[Shortround6]

If true then why didn't RLM just continue funding Ju-89 / Ju-90 / Ju-290 development? The Ju-90 was powered by 4 x 820 hp BMW132 radial engines. Replace them with 4 x 1,200 hp Jumo211 V12 engines and you've got a decent heavy bomber ready for mass production by 1940.

Define decent?
The Ju 90 was a little dated aerodynamically, being a wide body JU 89 bomber for the most part. It's wing was huge, actually more square footage than a B-29. given the high drag and high structural weight it was going to need bigger engines than the Allied 4 engine bombers to perform the same.
And you are right into the problem the Germans faced historical. You could build two medium bombers for every 4 engine heavy and the Germans couldn't build enough aircraft as it was. At least until 1943. Attacking England or Russia with half the number of bombers, which couldn't go any faster or fly any higher wasn't going to change the balance of air combat in favor of the Germans, especially if they didn't have a long range fighter to go with it.

 

[davebender]

The Ju 90 was a little dated aerodynamically, being a wide body JU 89 bomber for the most part.

The Ju-89 was a heavy bomber. The Ju-90 would still be a heavy bomber (rather then the historical wide body airliner) if RLM had continued funding for the Ural Bomber program.

You could build two medium bombers for every 4 engine heavy and the Germans couldn't build enough aircraft as it was.

I agree. However that makes no difference as historically 1930s Germany was committed to building heavy bombers. So why not proceed with the Ural Bomber program rather then building a He-177 variant powered by 4 x Jumo 211 engines?

 

[Shortround6]

Maybe the Germans should have produced the JU 89 in large numbers.

It would have shortened the war considerably

It's aerodynamics were dated. It used the trademark "Junkers double wing" which was high drag. Please note that the JU 88 did not use this arrangement.
It also used an absolutely huge wing. this was one way of getting an large aircraft airborne when you had low powered engines but it does tend to restrict speed when more powerful engines become available.

A new airframe may have been needed by 1940-41 in order to be successful.

Without a "URAL" fighter to go with the "URAL" bomber the 4 engine heavies would have been nothing more than targets although this was not appreciated at the time.

I also tend to wonder about the historical accuracy of the claim that Germany had no strategic bombers.
Depending on how hard you squint your eyes there doesn't seem to be a big difference between a He 111 and an early Vickers Wellington. And the Vickers Wellington was a principle part of bomber command for several years.
Could a He 111 have an operational radius of 500 miles with a 2000kg bomb load? If it did then you could hit Belfast from Rouen or Glasgow from Lille or Glasgow from Stavanger. Pretty much any part of the UK that wasn't a sheep pasture could be hit.
If the operational radius is less than that then things get a bit more difficult.

Now this may not seem like much in later war terms but it was pretty much state of the art in 1940. Who else had hundreds of bombers that could fly any further with any more bombs?