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

Which is better, Me 262 or the Gloster Meteor?


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Admittedly if you have put nimonic hot end components in you have improved the Schwalbe considerably (the Americans did that, of necessity).

Then, there are all the other myriad of problems such as
- bad design rigour in terms of the undercarriage - liable to catastrophic failure If not the undercarriage, then watch our for the wings failing catastrophically
- poor rough field capability leading to inflexible deployment and susceptibility to allied targeting of concrete airstrips
- likelihood of flameouts due to surge
- very poor thrust to weight ratio (around half)
- poor thermal efficiency (around 20% difference)
- poor braking
- lack of air brakes
- poor integrity of construction - admittedly, this may be because they were using slave labour, but that was their problem - it fell to bits - they werent even game to do a roll in it!
- the axial flow engine was more susceptible to damage by gunfire, both because of its relatively large size (much longer) and being more flimsily built

Apart from that it was not all that bad, really.
 
I was not aware of signficant problems with the wings and would appreciate where you got that from.
- poor rough field capability leading to inflexible deployment and susceptibility to allied targeting of concrete airstrips
Show me any WW2 jet that operated from grass strips. In fact, show me any jet that operated from grass strips before the Jaguar which is the first I can think of.
- likelihood of flameouts due to surge
Again show me any early jet that wasn't suseptable to flame outs. Note, even the Hunter a plane I am very fond of in its first version, flamed out every time the guns were fired.
- very poor thrust to weight ratio (around half)
And the Meteor was how much better? Show me any early jet that was much better.
- poor thermal efficiency (around 20% difference)
On this you might have a point if you can tell me what your comparing things with.
- poor braking
Somethng a lot of german aircraft had a problem with
- lack of air brakes
True but it had other features used for many years and the lack of which didn't stop it being a success.
- poor integrity of construction - admittedly, this may be because they were using slave labour, but that was their problem - it fell to bits - they werent even game to do a roll in it!
Where on earth did you get that from
- the axial flow engine was more susceptible to damage by gunfire, both because of its relatively large size (much longer) and being more flimsily built
I don't know how much you know about jet engines but I promise you that it was no more vulnerable than any other jet of its time. All jets are wide open to damage from anything hitting them be it a bullet or a stone. Even modern ones have to be careful and they are far stronger than early engines.

Apart from that it was not all that bad, really.
Wrong again, it was exceptional. Immune to interception when up to speed and able to pick its time and place to attack despite vast odd, I would say it was better than OK. Show me another plane in history of any time period that could do that. The F15 would be the only contender I could think of, another not bad aircraft.
 

For the most part, all this could have been applied to just about any early jet in one capacity or another.

Show me any WW2 jet that operated from grass strips. In fact, show me any jet that operated from grass strips before the Jaguar which is the first I can think of.
I seen L-29s operate from grass strips. I know the MiG-23 can as well.
 

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i) Some increase in critical Mach number, however, probably resulted from the 18.5 leading-edge sweepback.
OK. Some. But if so, why was its critical Mach number less than that of the Meteor? It means it was pretty insignificant, or that the Me262 was worse to start off with. This is borne out by the source Design for Air Combat: (DESIGN FOR AIR COMBAT)
In terms of sweepback, the Me 163 Komet is discussed briefly and its reasons being given primarily for aerodynamic balance and to increase the moment arm on the control surfaces of the wing's trailing edge... In terms of the Me 262, it says:
"The more conventional Me 262 was originally designed with straight wings. But, because it was one of the world's first high speed aircraft not to have the forward weight concentration of piston engines, it turned out to be tail heavy. In order to restore the balance between the lift and mass centres, the wing outboard of the engine nacelles was swept back, as it had been on the DC3 airliner for similar reasons. Eventually the Me 262 was given a leading edge sweepback of 18.5 degrees across the span, a modest sweep which had little effect on drag..."


ii) In addition to improving takeoff and landing performance, the slats improved the high-g turning capability in maneuvering flight.
If it improved take-off and landing performance, I dread to think what it would have been without them. The take-off and landing performance was abysmal, as is confirmed by the statement in Me262PilotDebrief that they were developing assisted take-off systems. They needed between 2700 to 3300 feet on a concrete runway for take-off and landing with an experienced pilot. Fey recommended adding another 1050 feet for an inexperienced pilot. The landing speed of 155 mph made it not much better than Concorde's 170 mph. You can't land in a dirt field at that speed.
As I mentioned with regard to maneuvering, the structural integrity of the aircraft was appalling, as is indicated by the ME 262 Projects feedback:
"...a detailed analysis of landing gear stresses was directed. This process revealed that a shock loading was generated by the spin-up forces of the large, heavy main wheels, which had to be reacted into by the wing landing gear attachment structure. This placed a severe demand upon wing spar area and the airframe simply had to absorb these forces. Over time, this would have had a devastating effect upon the aircraft..." That means it's going to fail, Glider.


iii) The Me 262 seems to have been a carefully designed aircraft in which great attention was given to the details of aerodynamic design. Such attention frequently spells the difference between a great aircraft and a mediocre one.
Well, now with the Me 262 Project implemented and the necessary rigorous design review being carried out, the chickens are coming home to roost on the Schwalbe's design.
iv) As compared with the German fighter, the Meteor was characterized by both higher wing area and drag area.
The small wing area and high wing loading is usually regarded as a liability in terms of dogfighting. Aerodynamically it has some plusses, but also a lot of minuses. This is borne out by the fact that the Meteor was more stable at high speed, more stable in a dive, could out-turn the Schwalbe. The low wing loading of the Lockheed P80 is usually pointed to as a point of superiority versus the Me 262. You can't have your cake and eat it too.
v) The paper compares the Me262 with the Meteor IV a post war development of the Meteor.
I didn't comment on what the paper said about the Meteor F IV. If I did, I would have quoted:
"...Clearly, the performance of the Meteor F. Mk. 4 was much superior to the performance of the Messerschmitt Me 262A ... To put this comparison in proper perspective, however, the Meteor F. Mk. 4 did not fly until after the end of World War II and had a thrust-to-weight ratio of 0.47 as compared with 0.28 for the earlier German aircraft..."
 
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The paper compares the Me262 with the Meteor IV a post war development of the Meteor.

It should have compared the 262 to the F.1. The Meteor IV didn't fly till the spring of 45.

Without going back on this thread, where did you come up with the 155 mph landing speed?

EDIT - I think your "155 mph landing speed" should have been "155 mph approach speed." Depending who you spoke to the Me-262 landed between 112-125 mph. From Zeno. page 4...

http://www.zenoswarbirdvideos.com/Images/Me262/ME262WendeL.pdf

Again from Zeno, this flight manual was prepared by the AAF.

http://www.zenoswarbirdvideos.com/Images/Me262/262PilotHandbook.pdf

Page 13 gives a stall speed "between 112 - 125 mph." I'd go with the 125 MPH if landing heavy.
 
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It's a bit optimistic to say that the Me 262 was particularly ahead in aerodynamics. It might look it, but in practice it's not. There's a nice report on ww2aircraftperformance.org which gives the drag for the various parts of both Meteor and Me 262. The lower drag of the Me 262 is pretty much all down to the smaller wing (itself having a knock on effect on takeoff/landing and turn performance)

I'm not sure what power issues you are referring to about the Meteor. There was a pretty well laid out plan for being able to adopt a variety of engines with increasing power. In 1943 alone you've got Welland, F2 and Goblin flying. Then various marks of Derwent as more power was got out of the engine (and eventually Sapphire and Avon engines mounted in the nacelles for some time to climb records postwar).
 
In spite of this far higher stress in the jet engine's most critical component, the endurance of the Derwent in service was over ten times that of the Jumo.

I'd like to see a wartime Derwent engine manual listing the presrcibed TBOs for the jet, and the actual values achieved in service - which were typically half or third that of the nominal values. People keep throwing around such statements 99% of the time without any idea whatsoever what were the actual TBO times for these engines...
 
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I'd like to see a wartime Derwent engine manual listing the presrcibed TBOs for the jet, and the actual values achieved in service - which were typically half or third that of the nominal values.
Agree. We had a lengthy discussion about this several months ago, mainly centered around the Welland, but I would say that although the Derwent had higher TBOs than the very first turbines, I doubt they ever made them, either attributed to operator error or teething pains.
 
To help with the reading I have amended your replies but have tried to retain the essence.
i) Some increase in critical Mach number, however, probably resulted from the 18.5 leading-edge sweepback.
OK. Some. But if so, why was its critical Mach number less than that of the Meteor?..."
I don't know which is the honest reply. However neither do you. I do know that the Me262 had a 50 mph advantage over the Meteor III which was operational so does it matter. A different question is why did the Meteor snake so much at high speed making it a poor gun platform at operational speeds. Again I don't know the reply but I do know the 262 is a hell of a lot faster and a better gun platform.

The Meteor III had a take off distance to 50 ft of 1,000 yards, not so different to the 262. As for the dirt road non concrete operating jets. I am still waiting for your examples. The Meteor also hadan approach speed of 150mph and a touchdown speed of 115mph which seems similar to the 262.
FJ gave the Mig 23 which is a similar timeline to the Jaguar and the L28 which was around 1960. Your imput would be appreciated Correct but the difference is OVER TIME. A peace time development built to the standards of the year 2000, are very different to those built in late 1944 when the life expectancy of a warplane was measured in months, we have all heard about war weary aircraft. If you have examples of any failing during the war in any numbers please support your statement, if not it doesn't stand.

See previous statement.

A few points here.
i) If you have a 50 mph speed advantage why dogfight?.
ii) The Meteor wasn't more stable at speed. It yawed making it unsuitable as a gun platform. It was also very tiring to turn even at moderate speeds.
iii) Are you saying that high drag area is a good thing on a high speed jet?
 
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I can not contribute to this discussion at the moment, with me being 11,000+ km from home and no sources available (and the fact that I don't have the time while on vacation over here...), but I would just like to thank all of the forum members involved in this discussion. Very good and interesting debate and discussion going on. I enjoy reading it the few hours a week that I have the time to do so at the moment.

So again thanks guys.
 
From INCO site - Inco?s Sudbury Nickel Mines were Critical During World War Two (Part 6 of 7) ? by Stan Sudol Republic of Mining

"One of the most noted contributions during the war was the invention of a new alloy for jet-propelled aircraft engines by International Nickel metallurgists from the Henry Wiggin Company Ltd. facilities in Birmingham.

This new alloy called "Nimonic 80" allowed the jet engine's turbine parts, particularly the blades, to operate for long periods under tremendous stress, high heat and corrosive exhaust without deforming or melting. This new alloy was superior to German aircraft technology. The first British airplane outfitted with the new engine was the Meteor which first flew in 1943 and was finally approved for the air force in July, 1944.

The RAF Meteor squadrons were mostly used to counter the threat from the 7,000 V1 flying bombs that Germany fired across the English Channel at Britian. The Meteors could achieve a top speed of 480 m.p.h. This speed was fast enough to allow the Meteors to fly alongside the V1s and 'knock' them out of the sky by using their wing tips to flip the rockets on their backs.

After the war, the "Nimonic 80" nickel alloy set the stage for a revolution in jet propelled aviation. Inco research scientists would go on to be responsible with the development of about 80 per cent of the specialized nickel-based super-alloys that are used in jet engines today..."

From CHAPTER VI: Soviets in the Air

MIG Fighters with Rolls-Royce Turbojets

In 1946 the Soviets bought fifty-five Rolls-Royce centrifugal compressor type turbojets — twenty-five Nenes and thirty Derwents. These Rolls-Royce engines, the most advanced in the world for the time, were well suited to Soviet production methods and introduced the Soviets to the use of a centrifugal turbojet. Up to 1947 Russian jets were all of the axial-flow type based on German designs. These Rolls-Royce turbines proved to be the best possible equipment for the MiG-15, which was designed by Siegfried Gunther and put into serial production under the name of the Soviet designers Mikoyan and Gurevich. Gunther was brought to Moscow and appointed chief designer in the construction office in Podberezhye.

Two versions of the Rolls-Royce engines were produced at Engine Plant No. 45 near Moscow from 1948 to the late 1950s. The plant was toured in 1956 by U.S. Air Force General Nathan Twining, who noted that it contained machine tools from the United States and Germany, and had 3,000 workers engaged in producing the Rolls-Royce Nene.

In 1951 the American counterpart to this Rolls-Royce engine was the Pratt Whitney J-42 Turbo-Wasp, based on the Nene, but not then in quantity production. When the Korean War broke out in 1950, therefore, the Russians had thousands of improved Rolls-Royce Nene engines in service powering MiG-15s, whereas the U.S. Air Force had only a few hundred F-86A Sabres with comparable engines. Several engines from MiG-15s captured in Korea were evaluated by the United States Air Force. Reports were prepared by engineers of Pratt Whitney Aircraft Division of United Aircraft Corporation, the Wright-Patterson Air Force Base, and Cornell Aeronautical Laboratory. We know from these analyses that by 1951 the Soviets had two versions of the original Rolls-Royce Nene in production quantities. The first version, the RD-45 that powered an early MiG-15, was a direct copy of the original Rolls-Royce Nene and delivered 5,000 pounds of thrust. The second version of the RD-45 delivered 6,000 pounds of static thrust at sea level and 6,750 pounds of thrust with water injection. The turbine blades in the Soviet RD-45 engines were made of a stainless steel alloy of the Nimonic-80 type, while the burner liner and swirl vanes were made of Nimonic-75. Parts of the Nene sold to Russia in 1948 were fabricated from Nimonic alloys — "Nimonic" being the registered trademark of Henry Wiggin and Company of Birmingham, England. Both Nimonic-75 and Nimonic-80 were developed by Mond Nickel about 1940, and the specifications had previously been published by the Ministry of Supply in the United Kingdom on the grounds that it was nonstrategic information.

The RD-45 (Nene) was produced in Moscow and also at Magadan from 1951 onwards, at Khabarovsk, at Ufa Plant No. 21, and at the Kiev Plant No. 43 from 1951 until sometime after 1958.

In 1967 the Soviet Strategic Air Force operated about 120 Tu-14 Bison bombers, 70 Tu-20 Bear bombers, and 1,000 Tu-16 Badger bombers. The Soviet Navy also operated these three types of aircraft.

From the information in Table 6-1 we can trace the operational jet engines of the 1960s from the Junkers and BMW prototypes taken from Germany at the end of World War II or from those sold by the Rolls-Royce Company as "peaceful trade" in 1946. Both groups of prototypes were developed by German engineers transferred to Russia as forced labor, with equipment and instruments imported as "peaceful trade." When the K-series and the AM-series turbojets were well along the development road the Germans were returned home. The Soviets have had no difficulty since in making design improvements to the original German and British concepts and technologies. These are the engines that power operational Soviet military aircraft.

So were German engineers responsible for the Russians dropping the axials and copying the British centrifugal designs?
 
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An American source writes of a comparison of the Schwalbe and the Meteor:
...After the end of the war the Me 262 as well as other advanced German technology was quickly swept up by the Americans (as part of the USAAF's Operation Lusty), British and Soviets. Many Me 262s were found in readily-repairable condition and were confiscated. The Me 262 was found during testing to have advantages over the early models of Gloster Meteor. It was faster, had better cockpit visibility to the sides and rear (mostly due to the canopy frame and the discoloration caused by the plastics used in the Meteor's construction), and was a superior gun platform as ...early Meteors had a tendency to snake at high speed and exhibited "weak" aileron response.
The Messerschmitt ME 262
Note that in order to rigorously test the Schwalbe for a satisfactory period, the Americans had to replace the original turbine hot end components with Nimonic. There was an element of sour grapes from some in the American camp to the British achievements in jet engine technology because it reflected badly on them that a nation with just 40% of their population had managed to beat them to it. At least the Germans had a more comparable population (75% that of the US).

In terms of visibility, the Meteor F III had a much improved bubble canopy. Against the charge of instability, Galland says in his book "The First and the Last" that the Schwalbe was also unstable at high speed and was hopeless as a low level bomber for this reason and also for its short range:
"...According to its flying properties and its safety conditions it was highly unsuited for an aimed-bomb release; diving or gliding were out of the question because of the unavoidable excess of the permissible top speed (i.e. unlike the Meteor, it had no air brakes). At speeds of over 600 mph the aircraft became uncontrollable..."
Also the NASA article (ch11-2) concurs that "snaking... plagued many of the earlier jet fighters."The fact that an up-engined Meteor F III set the world speed record in November of 1945 indicates that, if anything, the shoe was rather on the other foot in this regard. In the early 50s Adolf Galland flew Meteors in the Argentinean Air Force, which had obtained a hundred of the aircraft in 1946. Fifty were true F IVs, but the other fifty were refurbished war surplus ex RAF Meteor F III aircraft which had been re-engined with Derwent Vs. The Argentinean witnesses reported:
...The flight lasted about an hour and when it was finished, he said: If the Me-262 had had the Meteor's engines, it would have been the best fighter in the world! He qualified the plane of being very good and of having very refined lines...

Although the Meteors did not engage with Schwalbes and vice versa, the later Meteor F IIIs did encounter and engage with Fw 190s over the low countries.
"...The biggest frustration for the pilots of 616 Squadron was that they never clashed with the Me 262, or indeed with any German fighter aircraft. They came close towards the end of the war when a flight of Meteors encountered a force of Fw 190s, but they were forced to abandon their attack when other RAF fighters mistook them for Me 262s..."
It would be an absolutely futile exercise for them to engage with Fw 190s if they then had poor aileron response. The British pilots were forbidden to fly behind enemy lines because if they were to come down, the secret of Nimonic would be out. If it was too late for the Germans by that time, it certainly was not for the Soviets. (By the way, the Meteors on the continent had to be painted white to stop "friendly" fire from people who mistook them for Me 262s. They were still fired on...)

Back to the original source again:
...The Me 262 did have a shorter combat range than the Meteor...

...Messerschmitt also conducted a series of flight tests with the series production Me 262. In these dive tests, it was established that the Me 262 was out of control in a dive at Mach 0.86, and that higher Mach numbers would lead to a nose-down trim that could not be countered by the pilot. The resulting steeping [sic] of the dive would lead to even higher speeds and disintegration of the airframe due to excessive negative g loads...

The Messerschmitt ME 262

A Schwalbe would have to throttle right back if it found itself in a dive with the Meteor, running a risk of flame-out if it was done too quickly. As mentioned, the Meteor had air brakes, the Schwalbe didn't. With its low wing loading and better acceleration and deceleration, the Meteor could maintain relatively high thrust and have several strategies to take the Schwalbe out before it was able to respond.

Extract from the Me 262 A1 Pilots Handbook -

Changing Power in Flight: Move the throttles slowly forward or aft...

Specific instruction for take-off:
Note: By opening up the throttles too fast up to 7000 rpm there is a danger of causing cavitation [read surge] in one of the compressor stages. That is, by running up too quickly the compressor is overloaded and the smooth air flow breaks up just as it does over a stalled wing. If the take-off is continued, insufficient air flows through but the same amount of fuel is injected, resulting in insufficient power...

Without sufficient power, the plane was likely to destroy itself on take-off anyway. But if it managed to struggle into the air, it should also have been added here that there was a high likelihood of destroying the compressor or alternatively burning out the turbine blades and hence destroying the engine as the air flow dropped and the air-fuel ratio plummeted. But on the other hand, this contingency is also covered later in the Handbook:
Broken Vanes in Jet Unit:
Indicated by - vibration in the unit
Action - turn off the jet to prevent fuel lines from breaking and causing a fire.
 
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Some interesting stuff in the previous posting. If I may comment on the following.

I don't think that the Meteor ever engaged Fw190 fighters in the air or any other german aircraft but I will come back to that in a moment. It has been reported but I don't remember seeing this in the squadron records but it was a whjile ago and my memory could well be wrong. It is also untrue to say that all Meteors were painted white only the first four EE239, EE235, EE240 and EE241 sent to europe on detatchment to Melbroek were painted white. Before combat operations started these were replaced by more up to date versions of the Meteor.
It also wrong to say that Meteors were banned from operating behind enemy lines, its an often repeated statment but incorrect.
Meteors made a number of attacks behind german lines often attacking transport and other targets as well as airfields and on the 24th April two were damaged attacking Nordholtz. It was on one of these attacks where Meteors almost made their first air to air kill on 3rd May. Of all aircraft it was a Fi 156 Storch but when checking the gun footage it was deemed that the Storch had just landed with its wheels on the ground and therefore it didn't count.
They did try to use Meteors against German fighters keeping two manned aircraft on the runway for long periods near Brussels but the only interceptions were of friendly aircraft. On the one occaision where a German Jet was plotted (9th April) the runway was blocked by 149 wing aircraft preparing for a mission. An nterception was attempted but by the time they reached 30,000ft they were unable to close.

Re friendly fire concerns. The 2TAF were quite used to being attacked by the USAAF, there was a phrase going around
When we fire, the Germans duck
When the Germans fire, we duck
When the Americans fire, everyone ducks.

At least the Meteor could simply outrun the threat. Above quote from 2nd Tactical Airforce by Christopher Shores.
 
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Thanks for the correction, Glider. There is a lot of information there which must have come from a log of Meteor operations at the time... is it published in a book?

I know this is strictly off-topic, but there is some interesting information on Austrlian F8 Meteors in Korea, and their encounters with MIGs:

It seems to have been often outnumbered, and the opposing pilots were quite often experienced Russian fighter aces ex WWII. The Australian pilots protested that they had been trained for ground attack (see below). Also note that the MIG was a pure fighter, the Meteor was pretty handy at ground attack and could give a good account of itself in a dogfight too.

Australian War Memorial - Out in the Cold: Australia's involvement in the Korean War

Meteor Operations in Korea


Jan J. Safarik: Air Aces Home Page

"Another important change in the F.8 was, of course, still further uprated engines in the form of Derwent 8 engines with 1,633 kilograms (3,600 pounds) thrust each. Other changes included structural strengthening, a Martin-Baker ejection seat as evaluated earlier on the F.4, and a revised "blown" cockpit canopy that provided improved pilot visibility. The F.8 could carry two 450 kilogram (1,000 pound) bombs or sixteen rocket projectiles."

"Although the Meteor may have been obsolescent in the 1950s, it served with distinction with the Royal Australian Air Force (RAAF) during the Korean War in the ground-attack role. The RAF began receiving Meteor F.8s at the end of 1949, most of which were modified to carry a radio compass, with the antenna in a small dome on the aircraft's spine. The RAAF received 93 ex-RAF Meteor F.8s for combat service in Korea from 1951 through 1953."

"The Meteor was used for escort duties at first, with the aircraft's initial combat mission taking place on 29 July. A month later, the Meteors mixed it up with MiG-15s and got the worst of it, with one Meteor lost and the pilot taken prisoner, and two others badly damaged. The Meteor seemed to be no match for the MiG-15, though Australian pilots protested that they might have done much better had they been trained for air-to-air combat rather than ground support, but by the end of 1951 the Meteor had been relegated to the ground-support role.
This was dangerous work, all the more so because a Meteor had to be held smooth and level on its firing run for its gyro-stabilized gunsight to operate accurately, making the aircraft vulnerable to ground fire. 32 were lost in action. Despite the aircraft's general inferiority to the MiG-15, the Australians were able to score at least three "kills" against the Soviet fighter with the Meteor. After the war, the F.8s were sent home to Australia, to be replaced by Commonwealth CA-27 Sabres in the mid-1950s.
Keith Meggs : The Gloster Meteor
 
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My info came from 2nd Tactical Airforce Volume 3 pages 540 to 543. Next time I go to the National Archives I will try to look at the squadron diary which is always a good place to check for this type of information.

Re the meteor as a GA aircraft, GA is always, has always and no doubt will always, be a risky business. At least the Meteor had two engines giving it a fighting chance of getting home.
 
I don't know why people have a problem with MTBOs of around 150 hours for the Derwent. The hot end materials used were Nimonic 75 and Nimonic 80. These were substantially the same as those used in the Conway, which was the first jet engine to achieve a MTBO of 10,000 hrs.

For a history of the man who led the team which developed Nimonic, see Leonard Bessemer Pfeil 1898-1969, a PDF document which can be downloaded from the royal society on rsbm.royalsocietypublishing.org . Their design life was aimed at 300 hrs, which was regarded as being "the nominal life of an aircraft in wartime." The criterion provided by Whittle was 0.1% elongation at 12 tonnes/sq.in. at 650 C.

He was a descendent of a Frankfurt banker who migrated to England in the 19th Century, I think. He was no relation to Henry Bessemer.
 
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Because in actual operation, early turbine engines were "hit or miss" in actually making TBO. Some of this was attributed to operator error as some former recip converts had to get used to watching EGT on start while controlling fuel to the engine. Hot starts and over temps can cut a TBO in half, if not cause the engine to self destruct at a moments notice. Other problems were with fuel controllers which were constructed with rubber bellows and seals that would fail prematurely due to their operational environment. You also had common quality problems encountered during manufacture from improper heat treat to assembly errors. Remember, this was a new technology that was rushed into service during WW2 and many of its inherent manufacturing bugs were not quickly worked out for years to come. As late as the Korean War you were seeing 2nd generation turbines like the J-35 and J-47 being changed out after 50 hours of operation and reached a 1200 hour TBO by the mid/ late 50s.
 
I don't know why people have a problem with MTBOs of around 150 hours for the Derwent.

My only problem is that it is undocumented, and we have no real idea what was the manufacturer's specs for TBO in wartime for the engine, nor what was the practical TBO that could be achieved in actual service (as this quite typically waay lower in practice than the paper numbers in all engines, due to hasty maintaince, pilot abuse etc.).
 
The other aspect to look at here is that if the Derwent had an achilles heel in terms of reliability, it might have been more the bearings rather than the turbine blades or the compressor. At 16,500 rpm they were pushing the envelope of the then state of the art for rolling element bearings.

The factor which is critical, I would think, is that bearings tend to fail fairly slowly compared to turbine blades. At the end of a sortie, the engine might be checked and found to have a noisy bearing, which would be a damned nuisance, but not catastrophic. A failure in a turbine blade is likely to be much more than just a damned nuisance.
 

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