The first real jet engine

[Shortround6]

The German axial flow compressors were actually not very good, having pressure ratios of under 4 to 1. Many of the centrifugal jets could match that and few exceeded it.
For the axial engine to really beat the centrifugal engine it needed to use a higher pressure ratio, this actually took several more years after WW II to get any significant advance (5 to 1 in not that much better than 4.1 to 1.) The Axial engines, while thinner were often much heavier for similar amounts of power.

The axial engine promised more power and better fuel economy, it took until the early 50s to fulfil that promise.

 

[Duske]

It is still a centrifugal flow turbine engine produced after WW2.
.
BTW, the Lockheed F-94 had a centrifugal flow engine was was capable of reaching mach 1 in a dive. The MiG-15 couldn't do it due to aerodynamic issues (critical mach number)

No doubt the Germans produced the first practical axial flow turbine engines used in production aircraft, but the Centrifugal engine was still a player until centrifugal engines were made more efficient and reliable and that didn't happen until after WW2

I don't believe the Avon was a copy of any German engine as it was being developed in 1945

Good to hear. No doubt about that the Whittle radial engine was a great design - due to it`s very simple construction by needing less parts as a real
axial one. That`s why North Korea is still using the MIG 17. It seems that nothing can ruin a radial Jet engine. More or less we are talking about a few working parts within the radial one..

Rollce-Royce had the Whittle one in full production - by not knowing anything about the German axial engine.
Right after the war they changed to the axial one - same chape. It`s a kind of funny - or ?
Unless you are telling me which Britisch axial Jet engine was available at that time ! NON - you bet

When visiting the RAF-Museum at Handon both engines were placed side by side. The Whittle one
was discribed as the first and best Jet engine ever. I got angry. Then a simple guard told me: The German
axial engine was the better one. So you better come down from your high nosed opinion.
The guard did know why - because he is confronted day by day with the same Problem.

 

[tomo pauk]

Sorry for my bad English but I`ll try my best..
The Soviets did capture some Me 262 as more than 1400 units were build. 350 were used in combat. Within the Luftwaffe the Me 262 had a TMO of only 2 hours. (time of overhaul) due to melting compressor shovel blades.There was a great lack of metal ingredients like mangan and kobalt for making the shovels heat resisting. Germany did send U-Boots toward Indonesia were does ingredients could be found on the sea ground. Almost all U-Boots were sunk. This was not known by the Soviets as they tested the Me 262. Many planes crashed. Unable to fix this problem the Soviets did build the Whittle Jet engine in license for the MIG 15. Due to the Whittle one could not reach Mach 1 they connected the first afterburner to that engine, developed by Junkers.
Called then the MIG 17.

The Avon was a copy of the Jumo 004 and BMW 003, no doubt about that as it was done in 1945.
When the British had something equal why then did they send such a week Whittle one into the air ?

A radial Jet engine used within helycopters is not a jet engine we are talking about.
None of your named axial Jet engines reached ever production as you said.

My intension was only finding out who was the first creating the first fully operatinal axial Jet engine. No doubt about that !

Your statements disagree with last two sentences, and it is not about language.
British have had axial jet engines in development before 1945, as provided by members that have proven track record here. Avon could not be a copy of both Jumo 003 and BMW 003, but just one of them. What one, and where is a proof?
No engine was called MIG 17.

 

[pbehn]

From what I have read a centrifugal compressor is best for low rates of flow and lower compression ratios, which describes early jets pretty well. Until the problems of stable axial compressors and stable combustion were solved a centrifugal compressor was just as good as an axial one. Most technologies advance step by step and an axial compressor was fairly well known from engine superchargers.

 

[swampyankee]

Centrifugal compressors are, in many applications, both more robust and more efficient than axial-flow units. Creare and NREC both have modern centrifugal compressor designs for gas turbines with stage pressure ratios of ten and more with acceptable efficiency -- polytropic efficiencies of about 0.8 -- and range of operation. Most engines under about 20 lbm/sec will use mixed axial-centrifugal compressors because axial stages start getting too susceptible to FOD, cost too much to manufacture, and start having problems with range of operation.

So, yes, modern engines are being built with centrifugal compressors.

Some history: Early Gas Turbine History. Aurel Stodola was also not German.

 

[Duske]

The German axial flow compressors were actually not very good, having pressure ratios of under 4 to 1. Many of the centrifugal jets could match that and few exceeded it.
For the axial engine to really beat the centrifugal engine it needed to use a higher pressure ratio, this actually took several more years after WW II to get any significant advance (5 to 1 in not that much better than 4.1 to 1.) The Axial engines, while thinner were often much heavier for similar amounts of power.

The axial engine promised more power and better fuel economy, it took until the early 50s to fulfil that promise.

Today we are talking of a jet-engine thrust of 120 kN. The Me 262 did show only 8 kN. It was the very beginning of a real axial Jet engine.
But with this one the Me 262 was 160 ml faster than any piston engine driven fighter.

 

[Duske]

From what I have read a centrifugal compressor is best for low rates of flow and lower compression ratios, which describes early jets pretty well. Until the problems of stable axial compressors and stable combustion were solved a centrifugal compressor was just as good as an axial one. Most technologies advance step by step and an axial compressor was fairly well known from engine superchargers.

It`s so simple: With the Whittle radial Jet engine the compressed air had to be transfered around some Corners until reaching the burning Chambers.
This did slow down the air flow. An axial Jet engine Shows a straight through air flow - nothing better than that. By having only one compressor the radial one reached it`s end very fast - by beeing unable reaching Mach 1. After the war all had just to encrease the Diameter of the compressor for getting a most powerful axial Jet engine - till today.

 

[pbehn]

It`s so simple: With the Whittle radial Jet engine the compressed air had to be transfered around some Corners until reaching the burning Chambers.
This did slow down the air flow. An axial Jet engine Shows a straight through air flow - nothing better than that. By having only one compressor the radial one reached it`s end very fast - by beeing unable reaching Mach 1. After the war all had just to encrease the Diameter of the compressor for getting a most powerful axial Jet engine - till today.

Yes I know, the early days of jet planes were full of stories about flame outs and compressor stalls, these were the problems that had to be solved with axial flow engines on both sides of the channel and indeed both sides of the Atlantic.

 

[Duske]

The Germans may have had the first operational jet engine. That does NOT mean that all others were copied from it.
It took 3-6 years to bring an engine (even big piston ones) from initial design to operational use.
Nobody took a captured engine, copied it , and put it into service in a year.

let alone modified one to make 2-4 times the power in one to two years after seeing a captured engine.

What`s wrong about a well running German axial Jet engine captured and opened by Rollce-Royce within a few hours,
Guess it would have taken them only a few month to copy this one and drive it to the first Rollce-Royce axial engine ever - as shown.

 

[pbehn]

What`s wrong about a well running German axial Jet engine captured and opened by Rollce-Royce within a few hours,
Guess it would have taken them only a few month to copy this one and drive it to the first Rollce-Royce axial engine ever - as shown.

Because by the time there was a captured 262 to look at the British already had their own axial flow engines, I have no doubt they looked with interest at the design but the concept was already in testing before a 262 went into service.

 

[buffnut453]

Because by the time there was a captured 262 to look at the British already had their own axial flow engines, I have no doubt they looked with interest at the design but the concept was already in testing before a 262 went into service.

Burn the heretic! How dare you suggest that any nation had ANY technological parity with Germany, let alone superiority.

 

[Shortround6]

Perhaps I misunderstood you. I thought you (or the historians you set store by) were claiming that the British and Americans copied or developed German designs after the war?
there is no question that things have advanced in the over 70 years since the end of WWII but there is also no doubt that both the Americans and British were working on axial flow compressors well before they ever got a look at the two German ones.
There is also little doubt that the compressors to beat in post war periods were the Allied centrifugal compressors and not the German ones.
The Compression ratio of the Junkers 004 B4 engine was 3.0 to 1 with a mass airflow of 43lbs/sec
The Compression ratio of the BMW 003 A2 engine was 3.1 to 1 with a mass airflow of 42.5lbs/sec
The Compression ratio of the JE J-33(I-40) engine was 4.1 to 1 with a mass airflow of 79lbs/sec
The Compression ratio of the DH Goblin II engine was 3.6 to 1 with a mass airflow of 60lbs/sec
The Compression ratio of the Derwent I engine was 3.9 to 1
The Compression ratio of the Metrovick F2/4 engine was 4.0 to 1 and it produced 3500lbs of thrust for a weight of 1750lbs (ony 120lbs more than the Jumo 004)

The Germans may have been the first to have an "operational" but that certainly does NOT mean that modern jets are descended from those engines except in the very loosest of terms.

You might want to check the speed of some of those piston engined planes too. The 262 lucky to be 160kph faster than the last of the piston engine planes not 160 mph

 

[tomo pauk]

What`s wrong about a well running German axial Jet engine captured and opened by Rollce-Royce within a few hours,
Guess it would have taken them only a few month to copy this one and drive it to the first Rollce-Royce axial engine ever - as shown.

Are you stipulating that Rolls Royce copied a 'well running German jet engine'?

 

[Duske]

Yes I know, the early days of jet planes were full of stories about flame outs and compressor stalls, these were the problems that had to be solved with axial flow engines on both sides of the channel and indeed both sides of the Atlantic.

Yes I know, the early days of jet planes were full of stories about flame outs and compressor stalls, these were the problems that had to be solved with axial flow engines on both sides of the channel and indeed both sides of the Atlantic.

Correct ! Herrman the German did design the J 79 engine of General-Electric. The most famous axial Jet engine ever - even used in the B 52 and in all other fighters of the USAF. But then he made a mistake by disigning an oversized afterburner which did lead to 15o crashes of the F 104 Starfighter and 126 killed German pilots.

 

[Shortround6]

It`s so simple: With the Whittle radial Jet engine the compressed air had to be transfered around some Corners until reaching the burning Chambers.
This did slow down the air flow. An axial Jet engine Shows a straight through air flow - nothing better than that. By having only one compressor the radial one reached it`s end very fast - by beeing unable reaching Mach 1. After the war all had just to encrease the Diameter of the compressor for getting a most powerful axial Jet engine - till today.

Hmmm, guess those guys who designed multiple stage engines using centrifugal compressors really screwed up. Like the RR Dart
and the Garrett TPE331

over 13,500 built.
Granted not a supersonic engine but sometimes common wisdom isn't so wise.

 

[pbehn]

Please don't forget that there was actually a war on. This war meant that projects like jet engines were put on the back burner in UK in 1939/40 due to the imminent threat at hand. By the same token it was given increased priority in Germany as an answer to daylight massed bomber raids. When discussing "operational" "reliable" and "in service" they were completely different concepts in 1944 for the RAF and LW.

 

[Duske]

Are you stipulating that Rolls Royce copied a 'well running German jet engine'?

Yes !

 

[pbehn]

Correct ! Herrman the German did design the J 79 engine of General-Electric. The most famous axial Jet engine ever - even used in the B 52 and in all other fighters of the USAF. But then he made a mistake by disigning an oversized afterburner which did lead to 15o crashes of the F 104 Starfighter and 126 killed German pilots.

Who are you discussing?

 

[tomo pauk]

Yes !

Where is your proof?

 

[Shortround6]

Correct ! Herrman the German did design the J 79 engine of General-Electric. The most famous axial Jet engine ever - even used in the B 52 and in all other fighters of the USAF. But then he made a mistake by disigning an oversized afterburner which did lead to 15o crashes of the F 104 Starfighter and 126 killed German pilots.

where are you getting this crap from????

The B-52 used Pratt and Whitney engines (of several different models) never a J-79 unless an experimental model or for engine development.

The over-sized afterburner had little or nothing to do with crashes. An approach speed of over 225mph with a dead engine did. Plane used blown flaps with bleed air tapped off the engine. Flying low level in bad weather in plane that glided like a brick meant very few engine failures weren't going to end in a crash/