Why Did the He 177 Fail?

[kool kitty89]

Once the convoy is spotted you can turn around and execute an attack run. In order to get a number of planes to attack a convoy the plane that does the initial spotting needs to shadow it to guide the other attacking planes (give position up dates). But the plane doing the shadowing cannot be zipping around at high speed burning up fuel at a high rate. The "strike force" may be able to use a shallow dive on the actual bomb run but even a 40 ship convoy doesn't cover a wide area compared to a city and going into the shallow dive before getting a visual (or radar contact) on the convoy may not work too well.

Shadowing (let alone cruising) at high speed wouldn't be practical, but in those situations wouldn't staying at higher altitude be preferable anyway? (as long as visual and/or radar contact could be maintained)

Granted, even if maintaining a distance and altitude that made AA defenses ineffective, once escort carriers are on the scene (or anything else carrying useful interceptors) that's another matter entirely. And as you said previously, any effective tactics would spur more aggressive countermeasures from the opposition.

That said, the Fw 200 itself didn't have particularly good altitude performance, top speed, or cruising speed, so a good deal of room for improvement on all fronts.

Using a bomber that is 50-75mph faster in 1942-43 doesn't mean the radar went away, or the even more AA guns, there are even more escort carriers.
The faster, newer bombers will have lower losses than trying to use Condors but they are not going to return the German success rate to that of late 1940.

I was suggesting putting more emphasis on developing a potent long range bomber/recon/patrol aircraft in the first place. Probably with greater emphasis on recon/patrol ability (with strike aircraft carrying out most actual attacks).

And with the Ju 89/90 actually starting development as a military aircraft, I'd think it would be the most straightforward one to continue development in the combat role than the Fw 200. (it does seem like the Ju 89/90 was the better basis for a heavy transport and recon/patrol/bomber than the Fw 200 though) Something intermediate between the Ju 89/90 and 290 in service in 1940 powered by Jumo 211s seems plausible.

Then again, putting greater emphasis on properly strengthening and militarizing the Fw 200 should at very least have been better than what they were working with historically. (and compared to the Bramo radials, Jumo 211s should have helped with both speed and altitude performance as well as improved endurance/range due to improved specific fuel consumption and reduced drag)

In terms of pure maratime patrol/recon work, though, it might have been more effective (and cost effective) to employ something more like a long-range twin engine aircraft like a long-range recon derivative of the Ju 88 or He 111. (high speed Mosquito-like unarrmed recon aircraft might not be all that suitable though given the loiter time required for coordinating a strike force -dropping to a slower cruise speed could be possible, but ruin the primary advantages of a fast, unarmmed recon aircraft; the He 111 might actually make a better basis than the Ju 88 there)

You also have the likes of the Do 26 and far more numerous BV 138 which certainly had the range/endurance advantage to rival or well exceed the likes of the PBY, but with more severe speed and ceiling limitations than the Fw 200 itself. The BV 242 may have been a more compelling alternative to the Fw 200 and possibly more compelling for continued development than the Fw 200 or Ju 90/290 (in the patrol/recon role at least; the 290 would likely remain superior heavy transport).

The Do 26 may have had more compelling speed and altitude performance if adapted to alternate engines (Jumo 207, DB 601, or Jumo 211) but given that extreme range/endurance wasn't as necessary and the BV 242 was significantly faster with a much higher ceiling and land based (while also viable as a seaplane via Ha 139) and likely to remain better performing with comparable engine and armament upgrades, it seems like the more competitive alternative to the Fw 200. (perhaps more of an argument between mass producing the Do 26 and BV 138 )


Strike aircraft could certainly be more optimized for speed, but that doesn't cover the patrol role. (and unless you could manage a WWII equivalent of the P-2 in terms of patrol, strike capability, and range, you'd need more specialized aircraft for strike and patrol)

 

[Koopernic]

What made it possible to successfully bomb the ships of convoy Faith from between 12000ft to 15000ft was the use of a computing bombsight, the Lotfe 7. Sights like the Norden, Lotfe 7, SABS II to work best needed a steady run up in which the relative motion of the target was tracked. The Lotfe 7 apparently did this part very well. The bombardier basically adjusted variable speed drives whose motion was linearized via trigonometric cams to compensate for bomb sight angle and height. This established target velocity and wind drift. The USAAF thought it could hit trains and they probably could with a stick of bombs. The actual run up to the bomb release also needed to be steady. We are talking 10s of seconds though, not minutes.

Diving and accelerating would interfere with the bombsights accuracy.

The RAF's Mk.14 could bomb in a shallow dive but that sight could not compute target motion or offset for wind, that had to be estimated. Likewise the excellent Stuvi 5B with the BZA automate which could bomb in a dive. Late war Nordens could be equipped with a device to handle height changes.

It was theoretically possible to track and bomb while the aircraft was manoeuvring, battleships had the fire control to do this (eg the ford range keepers on USN ships).

You would need a 3 axis platform and a way of tracking the aircraft velocity and heading changes during the tracking, integrating accelerometers would be best but maybe just using air speed and heading would probably do.
That is a lot more mechanical computing to add for 1942. The bombsight would trace a fixed spot on the ground or sea irrespective of motion and the bombardier would make adjustments which would be in fact the wind/target motion.

This is I think beyond 1942 tech.

I do not believe an typical allied escort whether or frigat, sloop or destroyer was much of a threat to a level bomber at 12000ft in 1942. A cruiser would be a different matter but they were relatively rare.

My feeling is that it would be sometime in late 1942 that the allies would respond with better radar, proximity fuses and by then the use of guided weapons from higher altitude would change the game again.

The RAF's accurate bombing of Tirpitz is unremarkable: it was a 800ft by 100ft target. The only thing I find fascinating is how they accumulate the tallboy bombs aero ballistic data.

 

[Greyman]

What made it possible to successfully bomb the ships of convoy Faith from between 12000ft to 15000ft was the use of a computing bombsight, the Lotfe 7.

According to the wiki article;

"In his assessment of the action Admiral Charles Forbes, the Commander-in-Chief, Plymouth strongly criticised the troopships for not taking evasive action during the attack."

I imagine that would help accuracy quite a bit.


EDIT:
I'm no bombing/bombsight expert but the procedure for operating the Mk.XIV sight includes entering indicated wind speed and wind direction into the computer. I'm not sure if this is what you were referring to though.

 

[Juha]

...Convoy Faith was about 3 troop ships/merchantmen and 3 escorts. Only one of the escorts was a destroyer HMCS Iroquois. The Allied escorts were bulked out by low end frigates and sloops that were slow, had poor fire control, reciprocating steam engines instead of turbines, little armament and what there was only manually trained and whose radar was good for surface search of u-boats only. They were all about screening of U-boats using cheap microwave radar and a sonar. Faith it seems was attacked by, it seems, only 4 Fw 200's. There were two other warships in the distance, one of which was attacked.

Iroquois, the only true destroyer, had a type 291 air search radar that was fine for early warning. It was developed of metric ASV radar and was connected to a PPI display. It also had a secondary role in assisting anti aircraft fire by providing slant range to an accuracy of about 200m, which is pretty miserable...

As I have wrote already once, sloops were rather slow but powerfully armed ships for their size with good A/S AND AA armament, see e.g. https://en.wikipedia.org/wiki/Black_Swan-class_sloop

 

[Milosh]

There was 2 destroyer type vessels in Convoy Faith.

HMCS Iroquois, a Tribal-class destroyer that served in the Royal Canadian Navy.

HMS Douglas, aa Admiralty type flotilla leader (also known as the Scott-class) of the British Royal Navy.

HMS Moyola, K-260, a River Class frigate

HMS Swale, K-217, another River Class joining the convoy was also attacked.

 

[pattern14]

Getting back to the He 177, it was a flawed design, partly due to the twin engined bomber mindset of the Luftwaffe heads at the time. The 4 engined he 277 was a much more promising design. German bombers never had the success of their allied counterparts for a myriad of reasons, although you can trace the root of the problem back to the initial offensives. The Third reich did not envisage having to have an effective long range multi engined bomber force, as they believed in a short war that could be won with existing weapons. Technical woes, material shortages, lack of training and manpower eventually finished them off.

 

[fastmongrel]

The RAF's accurate bombing of Tirpitz is unremarkable: it was a 800ft by 100ft target. The only thing I find fascinating is how they accumulate the tallboy bombs aero ballistic data.

From 10,000ft (not actually sure of drop height) even a big ship like the Tirpitz is still a tiny target, if it was so unremarkable why wasnt everyone doing it. No617 and No9 were highly trained specialised units with possibly more combat and training flight hours than any other bomber squadrons before or since and even they only hit with 2 out of 29 bombs dropped.

 

[Shortround6]

German bombers never had the success of their allied counterparts for a myriad of reasons, although you can trace the root of the problem back to the initial offensives. The Third reich did not envisage having to have an effective long range multi engined bomber force, as they believed in a short war that could be won with existing weapons. Technical woes, material shortages, lack of training and manpower eventually finished them off.

Part of it the beginning was who the enemy was expected to be and what did you really need to hit the enemy. The He 111 seems to be rather unappreciated. The H-16 model (and earlier H models weren't that different) could haul eight 250kg bombs 1885km or cutting that to roughly 1/3 for a practical radius, about 390 miles. To meet weight limits the fuel tanks were not quite full. Leaving one 250kg bomb out would allow full tanks.
At any rate it is just about 390 miles from Emden to Manchester. About 380 miles from Heinsburg to Bristol. The Germans could cover a very large part of England from bases near the German border using HE 111s. London was a piece of cake.
The Germans could also hit large parts of France. Marseille was in easy range, La Rhochelle was a bit of stretch, 440 miles. From Saarbruecken is about 390 miles to Cherbourg. Brest and Bordeoux may have only been reachable with reduced bomb loads (four 250kg bombs?).
The British have a bit of a problem. While they can hit the Ruhr pretty well it is around 260 miles from Emden to Berlin. Many German cities are within range of early British bombers with decent bomb loads but Berlin was not.
GOing back to the Germans, it is around 600 miles from eastern Poland to Moscow. If we use the range X 1/3 + radius formula then the German 4 engine bomber would need a range of 2900-3000km to hit Moscow after the Germans took all of Poland. Please note that at this range a Halifax II might be carrying about 3000lbs worth of bombs. The Halifax II might not have been the most streamline plane going but it was using Merlin XX engines. A German 4 engine bomber that could hit Moscow in the Summer of 1941 (let alone the Urals) was a pipe dream.

What was going to do the Germans more good in 1940/41, 400 He 111s or 200 4 engine He X77s?

 

[Juha]

From 10,000ft (not actually sure of drop height) even a big ship like the Tirpitz is still a tiny target, if it was so unremarkable why wasnt everyone doing it. No617 and No9 were highly trained specialised units with possibly more combat and training flight hours than any other bomber squadrons before or since and even they only hit with 2 out of 29 bombs dropped.

Lancasters bombed from 12,000 ft to 16,000 ft, most between 14,000 ft and 15,500 ft. Cloud hinderance was noticeable especially near the end of the raid many planes lost the sight of the ship before the dropping point.

 

[SpicyJuan11]

Hey Juha, would you mind giving me the rest of the He 177 bomb bay dimensions? Many thanks!

 

[parsifal]

Tirpitz was an exceptionally difficult target to hit. She was protected on three sides by steep Fjord walls, had a full regt of flak protecting her, torpedo nets, smoke machines. Attacking aircraft had to either fly high, as was done in the November attacks and only had a short time in which to sight up the target, due to the canyon walls either side, or run the gauntlet up the Fjord itself.

On the day of the attack, the 617 sqn was lucky. weather was clear, but there were no fighters, cloud cover partially obscured the target, but it was still possible to see her. Blind bombing aids were used to assist in sighting up, but the final bomb releases were done visually. Smoke machines were activated, but the screen was only partial at the time of the bomb releases.

There was probably no better protected warship in the world at that time. And hitting a warship sized target at 16000 feet is never easy

 

[Juha]

Hey Juha, would you mind giving me the rest of the He 177 bomb bay dimensions? Many thanks!

Sorry but the drawing is on the cross-section of the fuselage, so no info on the lenght of the bomb bay, there might be that info in the text but I don't have time to look it. IMHO the easiest way to find out is to look on a good sideway picture of He 177, measure the lenght of the bomb bay and with the knowledge of the lenght of He 177 calculate the lenght of the bomb bay.

 

[kool kitty89]

Getting back to the He 177, it was a flawed design, partly due to the twin engined bomber mindset of the Luftwaffe heads at the time. The 4 engined he 277 was a much more promising design.

The 277 was a more advanced late-war design not really feasible as an alternative to the 177. The early proposal for developing the He 177 with 4 engines (namely DB 601 or Jumo 211) would be more practical but likely still suffer from some of the He 177's other teething problems related to advanced features. Still, it would at very least reduce the number of technical hurdles to overcome.

The Third reich did not envisage having to have an effective long range multi engined bomber force, as they believed in a short war that could be won with existing weapons. Technical woes, material shortages, lack of training and manpower eventually finished them off.

As Shortround06 already noted, the He 111 was relatively long ranged (though not as long as the Wellington), and pre-war the LW did have plans for long range strategic bombing capabilities with the development of the Ju 89 and Do 19 resulting from that. Walther Wever was the major proponent of this and the program died out after his death in 1936. (the subsequent Bomber A requirement that led to the He 177 did share some of the same goals, but even aside from the added dive bombing requirement it pushed a number of other advanced requirements beyond the scope of the older Ju 89, particularly the 500 km/h requirement)

GOing back to the Germans, it is around 600 miles from eastern Poland to Moscow. If we use the range X 1/3 + radius formula then the German 4 engine bomber would need a range of 2900-3000km to hit Moscow after the Germans took all of Poland. Please note that at this range a Halifax II might be carrying about 3000lbs worth of bombs. The Halifax II might not have been the most streamline plane going but it was using Merlin XX engines. A German 4 engine bomber that could hit Moscow in the Summer of 1941 (let alone the Urals) was a pipe dream.

A developed Ju 89 should have been able to manage Moscow (though likely not the Urals). The Fw 200 should have managed it as well, but bombload was fairly limited (4 or 6 250 kg bombs for the C-2) and the Ju 89 should have had a good deal more potential for expanded internal bomb capacity than the Fw 200. (the initial 16x100 kg bombs isn't very impressive, though)

If the He 111 could be modified to increase internal fuel capacity (or use drop tanks) along with perhaps 1000 kg of bombs and manage the same distance, that would probably be a good deal more cost effective and more useful for adapting between strategic and tactical bombing needs. (the Do 217 might be useful in a similar configuration, but obviously wouldn't be available in numbers by 1941)


In any of those cases you still run into the problem of escorts or limiting attacks to night bombing. (or possibly high altitude day bombing - Jumo 207 powered Ju 89 derivatives might have managed that, but again you're running into more specialized aircraft; 207s on the He 111 would likely leave it a bit underpowered and limit practical take-off weight or require RATO, though the added fuel efficiencies of diesels and high altitude cruise might still allow better long-range loadouts than a Jumo 211 powered He 111 with expanded internal/external fuel)

 

[SpicyJuan11]

Sorry but the drawing is on the cross-section of the fuselage, so no info on the lenght of the bomb bay, there might be that info in the text but I don't have time to look it. IMHO the easiest way to find out is to look on a good sideway picture of He 177, measure the lenght of the bomb bay and with the knowledge of the lenght of He 177 calculate the lenght of the bomb bay.

Yeah, I originally thought of doing that, but then I still don't have its depth. The reason why I want it in the first place is because I'm trying to compare it to that of the He 277.

 

[Koopernic]

Tirpitz was an exceptionally difficult target to hit. She was protected on three sides by steep Fjord walls, had a full regt of flak protecting her, torpedo nets, smoke machines. Attacking aircraft had to either fly high, as was done in the November attacks and only had a short time in which to sight up the target, due to the canyon walls either side, or run the gauntlet up the Fjord itself.

On the day of the attack, the 617 sqn was lucky. weather was clear, but there were no fighters, cloud cover partially obscured the target, but it was still possible to see her. Blind bombing aids were used to assist in sighting up, but the final bomb releases were done visually. Smoke machines were activated, but the screen was only partial at the time of the bomb releases.

There was probably no better protected warship in the world at that time. And hitting a warship sized target at 16000 feet is never easy

Steep fjord walls do absolutely nothing to protect from level bombers, they did however block the Tirpitz's own warning radar and FLAK. The Tirpitz was exceptionally poorly protected, the kriegsmarine reports of the time are emphatic that much more shore based FLAK was needed, in fact I can't even see any FLAK on the photo recon. The Luftwaffe was exhausted: extremely thinly spread, short on fuel, hadn't been told that the Tirpitz had been moved to a new Fjord, whose defences hadn't been built up. She was sunk in November 1944 as the Luftwaffe was collapsing and was short of men and machines.

The bomb aiming was not remarkable or exceptional from the height it was conducted considering that several dozen tall boys were dropped. It was well within the capability of any competent bomb aimer from the Luftwaffe, USAAF, RAF using a Lotfe 7, Norden or SABS2. Assuming bombing from 14000ft hitting a ship with a 100ft beam represent an error of of 0.7%. An 800ft length would be impossible to miss.

With nearly three dozen bombs dropped its surprising they didn't get more hits suggesting the heavy FLAK distracted the RAF crews somewhat.

Statistically it's the equal of dropping 36 marbles onto a 1cm wide model battleship from waist high. You are bound to get a hit.

No ones heavy AAA worked well at that altitude. The USN Reckoned that 80% of the aircraft it shot down were defended by 40mm bofors and 20mm oerlikon.

 

[Greyman]

Statistically it's the equal of dropping 36 marbles onto a 1cm wide model battleship from waist high. You are bound to get a hit.

Wow.

 

[fastmongrel]

Statistically it's the equal of dropping 36 marbles onto a 1cm wide model battleship from waist high. You are bound to get a hit.

That has to be the dumbest thing anyone has said on this forum all year. Try dropping the marbles whilst jogging past the 1cm wide model and see how many times you hit it.

 

[parsifal]

It turned out that way I guess, but it should have been so very different, and I firmly believe that no-one else other than the very best, like 617 could have attempted it.

The shore based flak support was not located immediately arounfd the target. It opened fire more than 13km away from the target. It was located mostly on the peaks, giving most of the flak excellent fields of fire.

There were two elements of the active defences that failed to work properly. The defending fighters were present, and were scrambled. If they had managed an interception, the heavily overloaded Lancasters,. stripped down as they were and lacking most of their defensive weaponary, would have been sitting targets. But the fighters were vectored to the wrong fjord.

The smoke pots, which so often had thwarted so many attempts previously had been emplaced, but were not yet functional leaving the target largely unobscured. As it was the target was still partially obscured by cloud cover.

As far as passive defences are concerned, I can assure you that mountains have a very real and adverse effect on bombing accuracy, when using unguided iron bombs. Mountains produce unstable air turbulence, affecting aircraft stability and the trajectory of the frefall bombs. Mountains affect sighting times for the bombers, meaning they have less time to sight up, account for wind currents and turbulence and identify the target correctly. Aiming up can take a few minutes to achive, especially when you are aiming for a relatively small precision target like a warship. Lastly, whilst the British benefitted from some impressive bombing and navigational aids by this stage of the war, the performance of these aids was somewhat affected by the presence of large landmasses around the target. Similar problems had bedevilled the BC attacks over the Ruhr at that time, which had far more gentle natural obstacles affecting the target.

A few things worked to assist 617 in this attack. The Tallboys they used were an incredibly heavy, but aerodynamic bomb. Whereas, even bombs of 2000 lbs weight would tend to tumble and get buffetted around by air turbuloence, the Tallboys were very stable and predictable in their descent path. Further, the flak was firing blind without benefit of radar, an unusual handicap, but it meant the flak was relatively innaccurate on this occasion. The air was still and visibility good.

Bombing any shipo from 16000 feet, with iron bombs without any real electronic assistance is dificult at the best of times, I can see youve never watched the progress of bombing runs on the range when you make claims like that. They are difficult even with the technology of the 70s and 80s which I am familiar with, but with the technology of 1944, it was more a matter of luck than good planning.

 

[fastmongrel]

Parsifal dont forget No9 squadron were also on the raid. No9 squadron (unlike 617 who used the SABS) used the standard Bomber Command MkXIV Automatic bomb sight.

 

[Koopernic]

Parsifal dont forget No9 squadron were also on the raid. No9 squadron (unlike 617 who used the SABS) used the standard Bomber Command MkXIV Automatic bomb sight.

The two sights would potentially work well together, the SABS IIB would calculate the cross and head wind and this could be communicated to the bombardiers flying those with the Mk14 who would enter the data manually.

That has to be the dumbest thing anyone has said on this forum all year. Try dropping the marbles whilst jogging past the 1cm wide model and see how many times you hit it.

The computing sights didn't take or require any intuitive guesses. They measured the ground speed with complete precision, they had access to the airspeed and air pressure within a fraction of a percent. Bomb tables for weapons such as the tallboy were meticulously measured. There was no guess work a in 'jogging past'. It was well within the range of ability of normal optics and machining. The USN and USAAF were the first with the ability, then the Luftwaffe then the RAF, then the Russian Air force.

Operation Catechism wasn't exceptional bombing by the standards of the bomb sight. Tirpitz was a sitting duck over 800ft long and 118ft at the beam. The crews, Bomber crews presumably being better than average RAF crews, had the discipline to disregard their own safety and use the bomb sight properly as per the instructions and drill. FLAK at that height was seldom effective.

I'm more impressed with the 4 Fw 200's who attacked convoy Faith and hit two moving ships with 2 bombs each(4 out of 8 dropped) and straddled and damaged several others while being shot at by a destroyer, sloop corvette and a Catalina.

A few things worked to assist 617 in this attack. The Tallboys they used were an incredibly heavy, but aerodynamic bomb. Whereas, even bombs of 2000 lbs weight would tend to tumble and get buffetted around by air turbuloence, the Tallboys were very stable and predictable in their descent path. Further, the flak was firing blind without benefit of radar, an unusual handicap, but it meant the flak was relatively innaccurate on this occasion. The air was still and visibility good.

Bombing any ship from 16000 feet, with iron bombs without any real electronic assistance is difficult at the best of times, I can see you've never watched the progress of bombing runs on the range when you make claims like that. They are difficult even with the technology of the 70s and 80s which I am familiar with, but with the technology of 1944, it was more a matter of luck than good planning.

I would say that had the Tirpitz been protected by an intercepting Geschwader or 'squadron' of Fw 190's perhaps up to half those Lancaster's, if intercepted, would have been shot down as happened to a similar raid in 1940 when 24 Wellingtons attacking Willehmshaffen lost 12 of their number to a squadron of Me 109E, a much less powerful fighter.

The absence of intercepting fighters was what made the raid possible and perhaps the wind patterns were stable. Everyone's Armour piercing bombs such as the Tallboy and Grand slam were made with precision so as to help them survive the impact of a hit and then penetrate the target, this would have made the bomb's aerodynamic characteristics consistent with the data accumulated on the bomb range.

Even from 16000ft the Tirpitz was not small; it was 118/16000 = 0.7375% for the beam and 800/16000ft = 5% across the length. So long as everything had been aligned and set properly those bombs were going to all get very close.