Replace Me-109 with Me-155?

[cimmex]

I would like to know from what source is the info that in Germany was lack of propellers during the war. This is pure nonsense. If you refer to pictures of planes without propellers, those are made after the war mostly in the British occupied zone because they ordered the groundcrew to remove the propellers to disable serviceable planes.
cimmex

 

[davebender]

Why?

2,000hp DB605D engine has just entered mass production. You would be hard pressed to find a piston engine with a better power to weight ratio during early 1945. Production cost was relatively cheap too. One could argue it would be better for Fw-190 / Ta-152 airframe then the much heavier Jumo 213 engine which required a longer nose plus rear fuselage extension.

 

[GregP]

Hi Cimmex,

I would like to know the English-language source for your assertion that a propeller shortage was NOT in effect. I have read it WAY too many times for there not to be some basis in fact, the most obvious one being the fact that the transportation system was broken late in the war, and any trucks or trains running on roads or tracks were attacked by hordes of Allied fighters, thus making supply a complex affair late in the war.

The LAST thing the Germans would do is to fly aircraft to the fuel source for refueling. They'd be seen and the fuel reserve tanks would have been destroyed easily.

So, right back at you, how can you claim it was NOT true? Any sources for that claim dispute?

 

[DerAdlerIstGelandet]

How about both of you post your sources, instead of playing a tit for tat game.

I would especially like to hear about a prop shortage. I have not read about it "too many" times...

 

[Shortround6]

Why?

2,000hp DB605D engine has just entered mass production. You would be hard pressed to find a piston engine with a better power to weight ratio during early 1945. Production cost was relatively cheap too. One could argue it would be better for Fw-190 / Ta-152 airframe then the much heavier Jumo 213 engine which required a longer nose plus rear fuselage extension.

Slight problem. The 2000hp take-off/sea level fades to 1800hp at 4900 meters and down to 1550hp at 6000 meters. Not much different than the Jumo 213A except it needs MW 50+ C3 fuel to pull the 2000hp. What was the 213A good for with MW 50?

 

[Aozora]

Why?

2,000hp DB605D engine has just entered mass production. You would be hard pressed to find a piston engine with a better power to weight ratio during early 1945. Production cost was relatively cheap too. One could argue it would be better for Fw-190 / Ta-152 airframe then the much heavier Jumo 213 engine which required a longer nose plus rear fuselage extension.

1) The DB605 had reached the end of its development/power potential with the D series. There was far more growth potential with the Jumo 213 and its more direct equivalent the DB 603 series, both of which were considered to be more reliable than the DB 605.

2) The DB 605 was only used in the 109. No sense in building one engine type for one aircraft type when both were at the end of their development lives without a great deal of work.

 

[cimmex]

How about both of you post your sources, instead of playing a tit for tat game.

I would especially like to hear about a prop shortage. I have not read about it "too many" times...

Well, I'm interested in WWII aircrafts since around 40 years and during the time I read hundreds of related books and magazines but never found any hint concerning lack of propellers during the war. There was no reason because no material shortage and the VDM or Schwartz production companies were never heavily bombed. Sure the transport to the units was hindered by strafing planes a lot but Germany had and has a very tight railroad net and when one route was blocked there was always a maybe longer alternative track. Mr. GreP made this claim several times in the past, so I asked in a very credible German forum LBB « Luftwaffe Bullet Board » Forum zur deutschen Luftfahrtgeschichte
cimmex

 

[riacrato]

1) The DB605 had reached the end of its development/power potential with the D series. There was far more growth potential with the Jumo 213 and its more direct equivalent the DB 603 series, both of which were considered to be more reliable than the DB 605.

2) The DB 605 was only used in the 109. No sense in building one engine type for one aircraft type when both were at the end of their development lives without a great deal of work.

There was still plenty of potential for the DB605, or room for improvement, if you want to put it negatively. Especially, in the supercharger department. DB605L would probably have been the more "definitive" DB605.

 

[Civettone]

There was far more growth potential with the Jumo 213 and its more direct equivalent the DB 603 series, both of which were considered to be more reliable than the DB 605.

I think you are wrong there. The DB 605 was way more reliable than the other two.

Kris

 

[davebender]

RLM wanted Genshagen retooled for DB603 engine production during 1944 but were unable to provide Daimler-Benz with the necessary machine tools. DB605D was the alternative as Genshagen conversion required far fewer machine tools.

It's difficult to believe anyone would whine about being forced to use DB605D engine. If it needs a better supercharger or turbocharger to improve high altitude performance then build one but the basic engine design was outstanding.

 

[Aozora]

I think you are wrong there. The DB 605 was way more reliable than the other two.

Kris

That's not what I am reading; eg:

If the 605 was way more reliable than the 603 and Jumo 213 then the Luftwaffe must have been in bad shape once all three engines had been adopted.

 

[davebender]

What does this mid 1943 report have to do with DB605 engines produced after teething problems were fixed?

 

[GregP]

When I get some free time, I'll see if I can dig up the references to propeller shortage.

Read it maybe 25+ years ago and it could take time, but it's out there somewhere. Can't say if it is right. I seem to remember Martin Caiden as part of it but could be mistaken there. Way back, I rode in his Ju-52 once. A VERY neat ride in an historic airframe. I lost my pics while moving and they were Polariod things, so they can't be replaced digitally.

Anyway, the gist was that transporation was so disrupted that the props were readily available but could not be gotten to the factory reliably due to Allied aircraft attacks on transport and there were airframes without props ready for delivery for 2 - 3 months before the collapse.

Can't say if I can find it again, but I'll look for it as I get time.

Until then, we KNOW there were fuel and pilot shortages, fuel reserves notwithstanding. It simply could not be transported without being destroyed. Lots of Bf 109's and Fw 190's didn't fly late in the war due to empty fuel tanks. It happens when the end is near and is notr slight on the service or the pilots OR the transport people. It is the fog of war that happened at the time. Nobody is saying there was a lack of bravery or desire, the fuel just wasn't there.

Kind of like in the movie Road Warrior. There WAS fuel, but nobody could GET it.

I have definitely read that props were there but in short supply.

So was food. Anyone who says otherwise is going against what I've personally heard from Germans people who lived it. 8 people who were there and KNOW.

If they couldn't transport FOOD, why would props be any different? The ONLY reason the airframes could be made in the last 2 months is the Aluminum and rivets were already at the factory in great numbers. That's from a Messerchmitt worker who was there and BUILT Bf 109's. I have NO personal knowledge of it but believe my old acquaintence, especially since he had pictures (actually photographic slides) that he showed a couple of times when we had a group together.

 

[Aozora]

What does this mid 1943 report have to do with DB605 engines produced after teething problems were fixed?

Have you got any report stating that the "teething problems" were fixed and that Petrick Mankau's conclusion that the RLM regarded the 605 as a sick engine, which remained problematic to the end of the war, is wrong? Note that even the 1943 extract was written some 18 months after the DB 605 was first introduced, which means that it should have been well past "teething problems".

 

[GregP]

So many DB 605-powered fighters flew that it is hard to believe there were major issues ...

 

[riacrato]

It is well known that the DB 605 had an oil problem through most of 1943. A problem that led to start und notleistung being blocked as a workaround an that was fixed by installing a larger oil cooler and radiatior and most of all an oil slinger to eliminate foaming. Nothing new here and I think I have that same book on my pc somewhere, can't remember if the author bothered to give a reference for that statememnt. He or they certainly aren't experts on the DB 605 development. That the teething problems could've been fixed earlier is another matter, but they still were basically that. I'll stop now, because probably or hopefully someone with vast knowledge about these problems will chime in but nothing of what you have posted relates DB 605 reliability to that of the 603 or the Jumo so I wonder how you can arrive at such a statement.

 

[Tante Ju]

Have you got any report stating that the "teething problems" were fixed and that Petrick Mankau's conclusion that the RLM regarded the 605 as a sick engine, which remained problematic to the end of the war, is wrong? Note that even the 1943 extract was written some 18 months after the DB 605 was first introduced, which means that it should have been well past "teething problems".

It's funny detractors always choose the last "problematic" report, but forget of papers mentioning the fix. The lubrication teething troubles of the DB 605 were fixed in the summer/automn of 1943. Mankau's book also reports this, but this has been missed by Aozora, unfortunately... the transprict of the relevant GL meeting has been transcribed full in kurfurst seite.

Kurfürst - Transcript of Generalluftzeugmeister meeting on 7th September, 1943.

BTW if anyone reads Mankau book, there is lot of reference and talks to DB 605 issues before September 1943 in GL meetings. Then afterwards - they cease.

Bottomline - even though the early 605 did not reach the robustness of for example, Jumo engines, it was quite sufficiently reliable even when introduced, even the first versions having a service life of 80-100 hours in practice. That's much better than early BMW 801s, or that achieved Napier Sabres achieved, like ever. The latter did not seem to last more than 20 hours even at the height of their "reliability" record.

Aozora needs to bring strong evidence to his claims into discussion to even be considered. By 1945, DB 605 series was producing 2000 HP, and they still saw potential for ca. 2300 HP in immidiate future. Two stage superchargers were developed for them, which gave outstanding (better even than Griffon 65 for exampe, which was the best of operational Allied V-12 altitude engines) altitude performance. Sure it had potential.

Of course in the long run DB 603/Jumo 213 series offered greater potential, at almost the same size and a bit more weight, but the 605 series still had potential IMHO.

 

[Aozora]

It's funny detractors always choose the last "problematic" report, but forget of papers mentioning the fix. The lubrication teething troubles of the DB 605 were fixed in the summer/automn of 1943. Mankau's book also reports this, but this has been missed by Aozora, unfortunately... the transprict of the relevant GL meeting has been transcribed full in kurfurst seite.

Kurfürst - Transcript of Generalluftzeugmeister meeting on 7th September, 1943.

"Teething troubles" hardly covers issues which took two years to resolve - still doesn't explain why M P say there were still unresolved problems with the engine right through until the surrender of the Nazis.

BTW if anyone reads Mankau book, there is lot of reference and talks to DB 605 issues before September 1943 in GL meetings. Then afterwards - they cease.

Because Mankau Pertrick are concentrating on material relating to development the 110 or 210/410. It's interesting that one way of resolving the issues with the 210 was to replace the 605s with 603s. In addition, reading about the development of Fw 190Ds and Ta 152s, for example, Kurt Tank didn't consider using the DB 605, which is a good indication as to the value he placed on it as an engine.

Bottomline - even though the early 605 did not reach the robustness of for example, Jumo engines, it was quite sufficiently reliable even when introduced.

Thus proving my point that it was not way more reliable than either the DB 603 or Jumo 213. "Sufficiently reliable" could mean anything.

That's much better than early BMW 801s, or that achieved Napier Sabres achieved, like ever. The latter did not seem to last more than 20 hours even at the height of their "reliability" record.

Evidence please, particularly with the claim about the Sabre.

Aozora needs to bring strong evidence to his claims into discussion to even be considered.

I'm not the only one who needs to produce "strong" evidence.

By 1945, DB 605 series was producing 2000 HP, and they still saw potential for ca. 2300 HP in immidiate future. Two stage superchargers were developed for them,...

What was the average TBO for this series? Any solid figures showing that DB 605Ds averaged more than say 20 hours?

...which gave outstanding (better even than Griffon 65 for exampe, which was the best of operational Allied V-12 altitude engines) altitude performance.

The Griffon 65 was a medium altitude rated engine, plus the Griffon had not reached its full power potential. Daimler Benz might have envisaged ca 2,300 hp, but that's purely hypothetical.

 

[Gixxerman]

and most of all an oil slinger to eliminate foaming.

I've never heard of an 'oil slinger' before have no idea what this is, just out of interest would anyone care to explain please
(with a diagram or pic if poss)?

 

[razor1uk]

I think the term 'oil slinger' could refer to a type of device that flung oil onto the walls of its collection chamber either by centrifugal rotation or via a nozzle/spray, that would allow air bubbles to escape the oil easier hence quicker, perhaps, or something with an edge or change of angle upon a shaft that would help stop oil going where it isn't needed by flinging it off at that point - like stopping it before a bearing or trying to minimise flung oil being lost into the piston bores loosing some of it to ring creep by and burning..

For a large engine needing a fast and efficient supply of cooled un-aerated oil, but to do this at the flow rates required would/could need to progress through an R&D period, let alone combat certification. Using a scaled up idea from earlier engines, might not always work, due to space, design changes and material requirements - the latter seems to be what 'hung up' there usage.


This DB605 related sub topic is going around yet again...
http://www.ww2aircraft.net/forum/av...ne-top-fighters-field-34534-2.html#post950376