Which jet was better, the Me 262 or the Gloster Meteor?

"One of the longstanding myths surrounding the Me 262 is that it should have been ordered into production sooner. Had the airframes been completed earlier they would merely have had to wait longer to receive engines. Thus, had the Luftwaffe exercised less caution and ordered the Me 262 into mass production at an earlier date, it would not have materially affected the situation."
"One of the major problems was that Junkers was producing a state-of-the-art engine without the proper materials. Ideally, nickel and chromium would have been used in the high-temperature areas of the engine. However, these materials were in short supply in Germany, and substitute materials were pressed into service for the production 004B. For example, the combustion chambers were made out of Tiefziehblech Flw 1010, basically a mild steel alloy that was coated with aluminum powder for heat resistance, resulting in frequent failures. The early production 004B engines had a service life of less than 10 hours, compared to almost 50 hours for the pre-production 004A that had used better materials. The flow through the engine had a tendency to break down at moderate speeds and high altitudes, resulting in compressor stalls. The fuel flow was also extremely difficult to regulate, the turbine burning out if the fuel was admitted too quickly, and flaming-out if admitted too slowly. More than any other single factor, the difficulties in getting reliable engines limited the Me 262's effectiveness..."

"...The general performance of the Meteor Mk I was inferior to the Me 262, but the Mk III closed most of the gap. Top speeds were roughly comparable, but the Meteor had better acceleration. The Derwent engines were more reliable than the Jumos in the Me 262 and had better throttle response..."
Me 262 Wunderplane Or Compromise

It should be noted that there was plenty of nickel available in Germany for armour plate. There would have been ample tied up in the hull of the Tirpitz alone, which never fired on an enemy ship, and spent most of the war hiding in the Norwegian fjords.

"> > What about the combustion chamber burnouts? This was caused by fast
> > throttle handling leading to excess fuel supply before engine
> > compressor spool up had diluted the fuel with air sufficiently. The Me
> > 262's Jumo 004B suffered from it, the BMW003 however was far more
> > immune from it because it had throttle limiting; something apparently
> > incorporated in the Jumo 004D which was entering into production as the
> > war closed."
>
>" So the engine which wasn't used was better than the engine which was used?
> That hardly helps the Me 262 as it historically existed."

"...The Jumo 004D engine was built, entering mass production and certainly
used on test aircraft. It was scheduled to reach the troops in the
first week of April 1944. It had two primary modifications: an
'acceleration limiter' that prevented over temperature situation
developing in the engine due to throttle handling and [f]uel injection
nozzles to provide finer atomisation at idling speeds and high
altitudes. Due to this and other modifications thrust went from 900kg
to 1050 and official MTBO went from 25 hours to 60 hours."

"I've seen documentation that looks to me that either whole aircraft
with Jumo 004D were to be sent out in the first week of april 1945 or
that the engines (as replacemements) were sent out. This was a month
before war's end..."

source The story of German U-864

Magnon said:

"...The Jumo 004B-4 reliabillity issue was in part caused by a lack of acceleration control in the primitive centrifugal governor based fuel delivery control system, this allowed the pilot to damage the turbine blades via too fast a throttle movement which would then need to be replaced.

Click to expand...

What you described there was typical of just about any early jet engines - now I'd agree more prone to the Jumo.

Your cut and past posts don't say much.

It should be noted that there was plenty of nickel available in Germany for armour plate. There would have been ample tied up in the hull of the Tirpitz alone, which never fired on an enemy ship, and spent most of the war hiding in the Norwegian fjords.

Click to expand...

The Tirpitz was an asset held in perpetual reserve. The Admiralty had always hoped on an improved situation where they would be able to get her into battle (which never happened). Trying to recover anything on that scale would have meant moving her from her protected position into a drydock capable of a large scale salvage operation and that just wasn't going to happen.

Also, the Nickle itself was worthless to the BMW-003, Jumo 004B and the Hs11 without Chromium.

The Jumo had stainless steel blades. Stainless has around 8% chromium...

The bottom line is that Germany had the materials, just misdirected them.

Actually, the (hollow) blades were made from a material called Cromadur, which is chromium, manganese, and iron...

The compressor components were made from aluminum coated mild steel.

The lack of raw specialty metals needed for the engines was simply not available as Germany's resources were stretched thin, so they had to improvise.

Cromadur has over double the chromium content of standard stainless!


The bottom line is that Germany had the materials, just misdirected them.

I see that you keep emphasizing that Germany had the materials, but misdirected them.

The fact of the matter was, that when Germany desperately needed the raw materials for these engines, it was too late, and the sources for the materials were no longer available.

Had the RLM taken a bigger interest in Heinkel's He280 and what the combat jet aircraft offered in the late 1930's, then the jet engine would have been developed in a time when Germany's resources were available in larger quantities. Even if they had gotten behind Messerschmitt and his proposals in 1941, there was still time to develope the jet engines with the right materials, but that opportunity was passed over as well.

I also see you make reference to "steel" being a component of the Cromadur and Tinadur. Steel is iron containing carbon to give it strength, which was not present in the custom alloy. It was iron, which came from Sweden combined with the rare and exotic metals which came from various areas within the shrinking Third Reich.

The iron used in the custom alloy was there because of other needed materials not being available, so they had to use iron as a substitute, and in much larger quantities to make up for shortages of the other materials. This resulted in a much heavier composition and prone to heat fatigue and subsequent failure.

Krupp manufactured the Cromadur alloy, and it's composition was as follows:
12% Chromium
18% Manganese
70% Iron

You'll see references to Tinadur which was used developed and used to some degree in the late production 004B engine, and it's composition is as follows:
6% Titanium
12% Chromium
18% Nickel
64% Iron

And as a side note, Stainless steel is an alloy of Iron and a minimum of 11% Chromium.

The bottom line is, Germany did not have the materials available late-war, and had to improvise...

I didn't refer to "steel" as a component in lieu of iron. My source did, and I thought it of so little importance that it was not worth correcting.

The bottom line is also that all you are doing is google-copy-paste whatever negative you can find on the plane. Clearly you knew the Me 262 to be inferior and directed your "research" accordingly .

Sorry

If the shoe fits wear it...

I dont buy the argument about it being impossible to introduce the Me262 earlier than it was either. The argument to support this is basically that the engines were not ready before April '44. Might be true, but if the airframe was pushed forward, then so too would the engine completion....and the desaign and development of the engine had been completed some months or years before that April'44 date.

In other words, if the airframe was pushed forwad, then so too would the other elements of the package

http://www.airforce-magazine.com/MagazineArchive/Pages/2008/November%...

© airforce-magazine.com material is under copyright by the Air Force
Association. All rights reserved

The bottom line is that time was required to research around the problem of suitable materials. It needs time, even when you throw every resource you have at the problem.

One of the problems that Heinkel and Messerschmitt faced early on, was Udet's disdain for those type of aircraft. When the He280 demonstrated it's capabilities in 1941, that should have amazed the RLM but instead received a literal yawn. The Luftwaffe leadership knew about the jet technology well before that point, but technically speaking, it wasn't until the demonstration of the He280 in the spring of 1941, that a jet powered combat aircraft proved what it could do.

Had it been recognized for what it was, and additional funding been made available for further developement for Messerschmitt and Heinkel, then the jet engine technology between the three manufacturers (Junkers, BMW and Heinkel-Hirth) would have had quite a head start in the war's timeline.

Unfortunately, there never was any significant backing by the RLM until later in the war.

What a difference 3 years would have made.

The British had that same problem... I think Machiavelli referred to something appropriate to this:


And Arthur Koestler:

parsifal said:

I dont buy the argument about it being impossible to introduce the Me262 earlier than it was either. The argument to support this is basically that the engines were not ready before April '44. Might be true, but if the airframe was pushed forward, then so too would the engine completion....and the desaign and development of the engine had been completed some months or years before that April'44 date.

In other words, if the airframe was pushed forwad, then so too would the other elements of the package

Click to expand...

The question is what are your variables. If you accept the political situation and the attitude towards / funding for jet engines as is I doubt any significant improvement can be made. And who says the airframe was pushed? It matured fairly normally as development proceeded and based on the results of the evaluation of the prototypes. It's not uncommon for one part of a system to mature faster than another one (see EF Typhoon).

With regard to Udet's lack of enthusiasm for jet propulsion in 1941, I have read somewhere that Hitler in about 1941 halted work on any weapon system that had a development timeline of more than six months, as he apparently believed that the Soviet Union would be defeated within that time.

If so, it's a prime example of "underestimating your enemy." The Japanese referred to it as "victory disease." Or from an ancient Greek perspective:

From a technical viewpoint, with regard to a previous comment about the importance of pressure ratio to jet engine efficiency, I quote:

The efficiency of a jet engine is strongly dependent upon the Overall Pressure Ratio (Combustor Entry Pressure/Intake Delivery Pressure) and the Turbine Inlet Temperature of the cycle.​

Source: Jet engine - Everything on Jet engine (information, latest news, articles,...)
The Derwent and Jumo engines had very similar maximum cycle temperatures, but the pressure ratio of the Derwent was 30% better than the Jumo...

In terms of the importance of acceleration and "specific excess power,":
The lower wing loading and quicker response of the Derwent to throttle would be crucial to maneuverability.

These factors were obviously not important in the Me 262s designated role of bomber destroyer.

I apologise again for the "cutting and sticking."

Magnon said:

"> > What about the combustion chamber burnouts? This was caused by fast
> > throttle handling leading to excess fuel supply before engine
> > compressor spool up had diluted the fuel with air sufficiently. The Me
> > 262's Jumo 004B suffered from it, the BMW003 however was far more
> > immune from it because it had throttle limiting; something apparently
> > incorporated in the Jumo 004D which was entering into production as the
> > war closed."
>
>" So the engine which wasn't used was better than the engine which was used?
> That hardly helps the Me 262 as it historically existed."

"...The Jumo 004D engine was built, entering mass production and certainly
used on test aircraft. It was scheduled to reach the troops in the
first week of April 1944. It had two primary modifications: an
'acceleration limiter' that prevented over temperature situation
developing in the engine due to throttle handling and [f]uel injection
nozzles to provide finer atomisation at idling speeds and high
altitudes. Due to this and other modifications thrust went from 900kg
to 1050 and official MTBO went from 25 hours to 60 hours."

"I've seen documentation that looks to me that either whole aircraft
with Jumo 004D were to be sent out in the first week of april 1945 or
that the engines (as replacemements) were sent out. This was a month
before war's end..."

Click to expand...

Another feature of the 004D was that it solved the vibration problems limiting it to 8700 RPM. It could safely go to 10,000 RPM with considerably increased thrust. (that would have been limited to emergency situations I believe, perhaps for take-off as well) The BMW-003E could also overrev iirc, but that was definitely limited to emergency use. (and was supposed to be carefully inspected after any such use)

The 004D also improved fuel economy somewhat.

Magnon said:

Cromadur has over double the chromium content of standard stainless!

"The production Junkers Jumo 004B-1 and the Jumo 004B-4 turbines and
stator blades used an austenitic 'stainless steel' like steel alloy
called tinadur or [a] concurrently used alternative called cromadur.
Tinadur was about 6% titanium 18% nickel 12% chromium with the balance
steel while cromadur substituted super-scarce nickel with manganese to
achieve an alloy of about 18% chromium, 15% manganese with only traces
of nickel with the balance steel. The BMW engines used a similar
alloy series called sicromal. This alloy was also used on gasoline
engined turbo superchargers and its shortage also explains the minimal
use of turbos on German aircraft."​

The bottom line is that Germany had the materials, just misdirected them.

Click to expand...

What gives you the idea they misused them and had enough early on?
That quote you site clearly states that turbochargers were also scarce due to limited supply of such materials.

There are other mitigating factors like advanced ceramics in development at the time, but that wasn't introduced before the war ended. (not sure if it could have been accelerated either, but perhaps)


The BMW-003C and D using more advanced reaction type compressors are pretty interesting though, but those were a little further off than the 004D (or slightly modified E).

There are a lot of other interesting designs, but probably most so the HeS 30 (109-006): very compact, powerful, and efficient, seems to have stalled partially due to funding limitations (the RLM seemed to favor Junkers and BMW considerably more), but mainly due to outright cancellation in 1943 when development was moving along fairly smoothly it seems. It was dropped along with the HeS-8 in favor of the HeS-011 which didn't make it before the end of the war.
In hindsight, it certainly seems like the HeS 30 should have been the main priority for the Heinkel-Hirth engineers, that or perhaps had Junkers taken more interest in Adolf Muller's designs before he left for Heinkel opposed to solely favoring the far more conservative 004 design. (that delayed things about a year I think) Granted, the design he'd been working on at Junkers hadn't been the one taken up at Heinkel . (supposedly it was the simplest and most straightforward design, though that would seem the obvious course for Junkers as well if they took more interest -obviously the most practical and quickly implemented design would be desirable)

Dropping the HeS-8 wasn't such a bad idea as it seems relatively wasteful an problematic in development, plus used the rather odd set-up with a radial turbine Ohain had initially used. (not so much problematic for development as cost prohibitive due to the large size requiring far more materials -which were, of course, quite scarce -I think the main problem was the stability of the annular combustion chamber -even the HeS 30 opted for flame cans and the 003 used can-annual chambers iirc -chamber is annular but with a series of cylindrical combustion chambers within) The earlier HeS-6 might have been more worthwhile, at very least for the short term as it at least seemed to be already working fairly well and had a decent amount of thrust (~1300 lbs in 1940), but was bulky so designs would have had to cater to it as the UK and US jets did early on. (probably most practical in the interim, and still with the rather costly radial turbine -unless the more durable nature of such a turbine would have facilitated full mild steel construction or a more dilute steel alloy -air cooling would be necessary, probably non-hollow hub vented cooling as with some 004s -far more suited to radial turbines)

It's rather unfortunate for the German Jet program that something more conservative and straightforward like DeHavilland's Goblin was not among the designs: simple with a single-sided centrifugal compressor, straight-through flame-can type combustion chambers, and a conventional axial flow turbine. (the Goblin had one of the shortest development periods of any jet engines of the war -granted it was also one of the few that had relatively unhindered development- but I think it was initially a privately funded project as well)



Anyway, one comment to the actual main topic:
The Meteor durring the war was a far, far less capable combat aircraft. The improvements made to the Mk.III helped a fair bit, but even then the performance gain was somewhat limited: once the much improved streamlined engine nacelles were introduced that had a major impact though. (the original stubby nacelles were the cause of the majority of the compressability/buffeting issues of earlier meteors -after that the tail surfaces became the biggest issue I think, but at much higher speeds than the nacelle problems)
If the Derwent II or IV engines were introduced before the end of the war (not sure if those actually saw full production though -soon after the war the new Derwent V became standard).

The only other issue was the ailerons being wired heavy to limit roll rate/stress due to concerns about integrity after a failure on one of the prototypes.

The Me 262 is a fundamentally superior arirframe though if you look purely from that aspect. Much cleaner high-speed oriented design. Thinner, higher aspect-ratio wing with slats to address low-speed lift issues. More flexible armament placement (I think 6 20 mm guns could fit reasonably, among other arrangements -the original plan for the meteor, but later found unacceptable).
Longer range as well, much more so with more efficient engines. (even the 004D; 003 more so -also lighter- not to even mention the HeS 30 )




Edit:
As for Udet, it's my understanding that he was the exception to the RLM's early lack of interest in Jets, particularly in the case of Heinkel and it was he who set the deal to allow Heinkel to merge with Hirth if the He 280 were to fly by April of 1941,
See: http://www.cressnet.ir/Journals/J_E...NEERING_FOR_GAS_TURBINES&POWER_2000_APRIL.pdf pg 196

The Germans were rolling out Tiger and Panther tanks until very late in the war, all with around 4.5% nickel in their armour plate. The Russians used about one third of that, but made up for it by inventing sloped armour, which gave them a similar result in terms of protection. The German tanks rolled to a stop in the battle of the Ardennes forest because they ran out of fuel. They ran out of fuel because the USAAF was destroying their synthetic fuel plants quicker than they could be rebuilt. If greater priority was given to the Me262 program, the bombers may not have got through. Instead of putting a couple of hundred very unreliable jets into the air, they should have been able to put a couple of thousand reliable ones. Just imagine two thousand Me262s against less than a thousand bombers!

With sufficient fuel, the Ardennes offensive may have worked. The Allies would have been in big trouble. Then again there was the A-bomb trundling along down the track...

I know its easy to make judgements with the benefit of hindsight, but I think it's fair to say they didn't get their priorities right in terms of giving nickel to the Me262 program.