Quality of serial built fighers

[CAPILATUS]

Some thoughts came up in my mind through out different topics...

The question is - were there any quality standads for sereal built fighters in Germany, USA, England in WWII? What was the limit for them?

Why I have asked - the serial built La were worse of "La-etalon" by up to 40km/h in horizontal speed at Sea Level, I've got some documental proofs for that. By the end of the war they came very close to etalon.

What's about German's ones than? Or may be sometimes serial built fighters came even better?

PS. Any links or documents proving or disproving are appreciated.

[Trexx]

I definitely do not understand the question...

[CAPILATUS]

quote:Originally posted by Trexx

I definitely do not understand the question...

OK.
For example, one P-51D standard was built and tested. It's shown speed at Sea Level 600km/h and 700km/h at 8000m. Afterward it was started for the mass production. After 1000 planes were built we're taking 1001st for flying test and it shows us 570km/h at ground and 680km/h at alt.

We can see the quality got lower. So the question was it fact for the mass producted planes in USA, UK, most interested in Germany in 1944-45. Or ALL the planes had the same flying characteristics as the first one.

[Trexx]

quote:Originally posted by CAPILATUS

quote:Originally posted by Trexx

I definitely do not understand the question...

OK.
For example, one P-51D standard was built and tested. It's shown speed at Sea Level 600km/h and 700km/h at 8000m. Afterward it was started for the mass production. After 1000 planes were built we're taking 1001st for flying test and it shows us 570km/h at ground and 680km/h at alt.

We can see the quality got lower. So the question was it fact for the mass producted planes in USA, UK, most interested in Germany in 1944-45. Or ALL the planes had the same flying characteristics as the first one.


Hmmm. I see.

[GregP]

In WWII, the continental United States did not suffer from enemy bombing raids. We also did not suffer from lack of raw materials, except for a distinct lack of alloys to make turbo-superchargers early in the war. Tungsten was in short supply (as a result, the P-39 didn't get the turbosupercharger the prototype had).

Therefore, there is no reason to suppose the U.S.A. suffered any "loss of quality" in series aircraft manufacture. We were not under "duress" in the factories.

The Japanese suffered loss of quality, mostly due to lack of raw materials and allied bombing raids on factories. There was no loss of ability or knowledge.

The Germans suffered from allied bombing raids, but were adamant about the quality of their machines. As a result, many German airframes were made that never got propellers or even engines. But the Me 109s that came off the assembly line in 1945 were good-quality machines, even if the design was dated. Around 1945, some were ready to fly, but never got any fuel.

The British also suffered from bombing raids, but never really suffered from quality loss in their aircraft. They seemed to have had no difficulty in getting Tungsten since most of their machines HAD superchargers.

The Soviets did suffer from loss of quality. There were several reasons. One was German bombing raids that resulted in moving the entire aircraft production facilities some thousnad or more miles eastward to get them out of range of the Germans. Another was lack of proper raw materials, forcing many Soviet designers to use wood instead of duralumin or aluminum in airframes, along with a lack of skilled labor. Still another was the general lack of Soviet-designed modern engines. The main liquid-cooled Soviet fighter engine line (Klimov) was a development of the Hispano-Suiza 12Ybrs. The main Soviet radial engines (Shvetsov, Mikulin) were developments of the Wirght Cyclone radials. Most of the better Soviet engines did not come along until after 1943. Soviet technicians also had a tough time with turbo-superchargers, and I suspect lack of proper raw materials was a major factor; Tungsten was not widely available to them. Another factor in Soviet aircraft performance was the quality of the fuel generally available to the Soviet Air Force. I believe it was mostly 87-OCtane and was not all that clean, being left in open drums a lot of the time. The Kliomv VK-105 might have been a nuch better engine had 150-Octane fuel been widely available. I do not know about the quality of Soviet oil supplies, but I suspect the oil they had was different than what the U.S.A. used since they were mostly operating in frigid weather and seemd to have little trouble starting and running engines whereas the U.S.A. had a tough time in ALaska with frozen engines.

The Stalin purges of designers and factory managers were a thing that never happened in the West, so our best designers survived and developed better engines and airframes instead of being shot.

Just some observations.

[Kutscha]

Not exactly true Greg.

When the Germans were looking at 1.98ata for the K-4 there was a comment made why they should go for this 1.98ata boost when the quality of the airframe was so bad. This was in official correspondence.

quote:The Germans suffered from allied bombing raids, but were adamant about the quality of their machines. As a result, many German airframes were made that never got propellers or even engines. But the Me 109s that came off the assembly line in 1945 were good-quality machines, even if the design was dated. Around 1945, some were ready to fly, but never got any fuel.

[CAPILATUS]

quote:Originally posted by GregP

In WWII, the continental United States did not suffer from enemy bombing raids. We also did not suffer from lack of raw materials, except for a distinct lack of alloys to make turbo-superchargers early in the war. Tungsten was in short supply (as a result, the P-39 didn't get the turbosupercharger the prototype had).

Therefore, there is no reason to suppose the U.S.A. suffered any "loss of quality" in series aircraft manufacture. We were not under "duress" in the factories.
I go along with, it's quite reasonable, but any documents can prove that?

quote:Originally posted by GregPThe Germans suffered from allied bombing raids, but were adamant about the quality of their machines. As a result, many German airframes were made that never got propellers or even engines. But the Me 109s that came off the assembly line in 1945 were good-quality machines, even if the design was dated. Around 1945, some were ready to fly, but never got any fuel.
I have some sources refering to bad quality of Germans airframes built in 1944-45, the same sources claim there was only one factory for Bf's in Hungary satisfying Bf-109 standards. What I'd like to know, as far this quality was so bad.

quote:Originally posted by GregPThe British also suffered from bombing raids, but never really suffered from quality loss in their aircraft. They seemed to have had no difficulty in getting Tungsten since most of their machines HAD superchargers.
Same as with American fighters, I need proofs or any refer.

quote:Originally posted by GregPThe Soviets did suffer from loss of quality. There were several reasons. One was German bombing raids that resulted in moving the entire aircraft production facilities some thousnad or more miles eastward to get them out of range of the Germans. Another was lack of proper raw materials, forcing many Soviet designers to use wood instead of duralumin or aluminum in airframes, along with a lack of skilled labor. Still another was the general lack of Soviet-designed modern engines. The main liquid-cooled Soviet fighter engine line (Klimov) was a development of the Hispano-Suiza 12Ybrs. The main Soviet radial engines (Shvetsov, Mikulin) were developments of the Wirght Cyclone radials. Most of the better Soviet engines did not come along until after 1943. Soviet technicians also had a tough time with turbo-superchargers, and I suspect lack of proper raw materials was a major factor; Tungsten was not widely available to them. Another factor in Soviet aircraft performance was the quality of the fuel generally available to the Soviet Air Force. I believe it was mostly 87-OCtane and was not all that clean, being left in open drums a lot of the time. The Kliomv VK-105 might have been a nuch better engine had 150-Octane fuel been widely available. I do not know about the quality of Soviet oil supplies, but I suspect the oil they had was different than what the U.S.A. used since they were mostly operating in frigid weather and seemd to have little trouble starting and running engines whereas the U.S.A. had a tough time in ALaska with frozen engines.
Well, I can't agree if it was matter of proper raw materials, if it was their mistake. It wasn't. The average life time of any fighter being involved in battles on the East front was about only 40-50hours. So no point to waste so expanive duralumin, to lose just in fly 40hours on the front. There is another point, it's well known the Soviets were ones of the world leaders in subsonic aerodynamics, they even had wind tunnel as huge as to allow'em to reserch any fighter with the original size. The matter of fact a friction ratio of wooden polished surface is less, than aluminium one. Sure the aircraft being serial manufactured suffered in quality, but not due to the reasons you described.

Back to fuel. Greg, you'd be surprised! I do not believe the Soviets had any problems with supply, no way. The even had fuel for Aerocobras being brought to them in huge numbers. I met some notes Russian pilots used higher octane fuel assinged for P-39 not because air regiments had no fuel for their VKs or ASHs engines, just because their planes got some extra power. It's very interesting, because I didn't meet any documents of any experiments with engines being tuned for different fuel, but I saw an interview with veteran serving in Yak regiment he insisted pilots used the fuel as "it was plenty of, BOTH".

general lack of Soviet-designed modern engines
??? Greg, it not a secret VK-105PF, VK-107, ASH-82FN engines are ones of the best in WWII.

The thing I tried to pay attention is quality of airframes which was not ideal for Russian mass producted planes. And I heard some that the same problem was in Germany in 1944-1945.

[GregP]

Hi Capilatus,

I believe the Yak-3/7/9 a,d the La-5/FN/7 were some of the best fighters of the war. It is very good to hear that fuel wasn't a real problem. I had heard otherwise, but ... again ... with no proof. I stand corrected.

The Soviet VK-105/107 and the Ash line of radials were good engines. I am not sure they were better than comparable American or English engines, but they were good engines. They HAD to be, and oeprated in climatic consitions that contemporary weatern engines could not. I was not denigrating Soviet design. I was making the point that the Germans were bombing Soviet factories, the factories were moved, and the best Soviet designs were post-1942.

Before that time, the Soviet planes were not low in quality, they were simply outdated, and were shot down in droves by the advancing Germans.

After 1943, the Soviet Air Force turned the tide on the Luftwaffe and achieved equality first, and the superiority.

I hope my point was that after 1943, the Soviet Air Force went from being targets to taking the offensive, an admirable turnaround and a very good statement of Soviet aeronautic achievement.

[ickysdad]

greg,
P-38's operated alright in the Aleutions ,alot better then they did in Northern europe . On tungsten Greg your forgetting that(if I'm not wrong) the US produced over 300,000 aircraft during the war including something like 10,000 P-38's(each with 2 engines) and 15,000-18,000 P-47's both planes had turbo's plus if I'm not wrong all the B-17's & B-24's had turbo's and those planes had 4 engines each. Also the US was turning out alot of special tungsten cored ammo for thier anti-tank guns if I'm not wrong and were doing it for British guns also.So evidently tungsten wasn't in too short of supply in the US. I'm thinking the Us was the largest producer at this time of tungsten.
On soviet engines and aircraft Gordon & Khazanov state that soviet planes did have 100 octane fuel by war's end but by then the USAAF & RAF had 150 octane fuel. They also state that soviet planes did have some problems with structural issues because of lack of certain strategic materials and that engines couldn't use augmented power hardly at all..

[Kutscha]

GE made some 303,000 turbo chargers, mostly the B type during the war.

[Mark J]

Most British aero engines of the war used SUPERCHARGERS. These are mechanically driven unlike turbosuperchargers which are exhaust driven.
Turbo superchargers need high quality alloys like tungston for the impellor that sits in the exhaust path and which drives the compressor impellor.
SUPERCHARGERS, being mechanically driven, don't have a high speed vane sitting in the exhaust and so don't need special alloys. I understand the supercharger impellors used in British engines were made from a 'normal' steel with conventional heat treating or case hardening. I also understand, the USA built most of the turbosuperchargers used during the war while most other nations used mechanical superchargers that didn't need tungston.

cheers

[GregP]

Yes, we built a lot of turbos in WWII, but we didn't have enough to keep up with the demand. The P-39 didn't get its turbo, and we put out a lot of non-turbocharged aircraft atht we would have preferred to be turbo units.

Superchargers are nice, but the limit of supercharging is about 4000 to 500 hp on piston engines. After that, they consume the extra power they produce.

I think that if you do the research, you'll find that U.S. turbocharger use started out as a trickle and gradually built up as we ramped up production. Production started out very slowly and didn't pick u[ untl around the end of 1942, as I recall. I may be wrong there, but I don;t think so. Yes, tehre WERE so turbo-supercharged planes like the P-38 around, but not in the numbers that were needed immediately.

[Kutscha]

The P-39 did not get turbos because there was still bugs to be worked out in them and the B-17 needed them.

America was not producing a/c in mass quantaties either, early in WW2.

If the superchargers had gone to fluid coupling instead of geared coupling not so much power would have been lost driving the gears.

[GregP]

Kutscha,

They STILL can't make a supercharged engine of much more than 5000 hp today, at least of a size and reliability level suitable to power a military aircraft on flights of several hours.

Sure, the Reno air races can and do have some powerplants that turn out 5500 - 5800 hp. but they run 8 laps at those power levels, and often don't even run that far.

Fluid coupling hasn't been able to change that in 60 years, so I don't see how it would have helped in 1943.

[ChrisMcD]

Just to add some points

1) British Superchargers - Rolls Royce, in particular, prefered to use the exhaust gasses for extra thrust. I cannot remember the exact details, but it was about 400 lbs of thrust which became very significant at higher speeds when the efficiency of propellors dropped off.

I agree with the comments about GE superchargers taking time to get into full production. You pick up comments about both the P40 and the early P51's (Apaches?) suffering from the lack of them. One theory about the useless Brit P38's was that the US was reluctant to risk letting the Germans get a look at their turbocharger technology. It makes more sense than most, when you consider that the P38 was supposed to be a fast climbing, high altitude interceptor that would obviously be crippled without the turbochargers that were so basic to it's design. A seconday theory is that Arnold got the UK Purchasing Commission to order P38's so that Lockheed could get large scale production lines planned without having to go thru Congress.

2) Quality of production. There was a big debate in 1940 when it was discovered that rebuilt Hurricanes were some 30 mph slower than new builds. Expected problems from the 'shadow' factories were only really evident on engines, where there were a number of quality control problems with batches from car manufacturers early on.

3) As I understand it Russian aluminium production took a while to build up and was not helped by the Germans taking out a lot of hydroelectic plants. So it was wood or nothing in the early war years. When things got better a number of planes were redesigned in metail (ie Lagg 7 to 9).

4) Russian engine development lagged (sorry) a bit in the early years of the war, so there was a tendency to keep structural weights low and to do a lot of work on wood/bakelite composites (ie Lagg 3). They had good metalurgy and did a great work of catching up. As I understand it the Russian copies of the Nene had better metals than the Rolls Royce ones.

5) Japanes engines appear to have been the ones most troubled by quality problems. The Nakajima Homare was a very compact design and later production models had a lot of problems. They also had a lot of problems with the lubrication of the DB 601 copies.

[GregP]

Hi ChrisMcD,

The British pumps were Turbochargers. In WWII, the term was Turbosupercharger. Later, it was shortened to Turbocharger.

Turbochargers are better than superchargers for engines that operate at a fairly constant RPM. They are less suited to racing automobiles that need power RIGHT NOW in the middle of a corner.

Aviation was a perfect application for them.

[BuzzLightyear]

Turbosuperchargers allowed for better fuel efficiency over mechanical superchargers, as well.

Fluid drive was promising. It was used in the P-63 Kingcobra and later in the F8F-2 Bearcat and F4U-5 Corsair. In addition to better fuel efficiency, they generally allowed for higher critical altitudes over machanical superchargers, with the added benefit of not having to shift gears. Climb and speed charts for planes with fluid driven superchargers are nice and smooth, like those for planes with turbosuperchargers.

[Mark J]

The Junkers 211 and 213 inline engines had fluid drive superchargers, as did the DB 601, 605 and 603. These engines were all running in 1939. The BMW 801 had a single stage two speed mechanical supercharger although it was latter adapted to run an exhaust driven turbosupercharger. German aero engines had good blower technology but were let down by the low engine ratings ( low forced induction pressure ) which reflected their generally low fuel rating so they couldn't raise the compression ratio's.

cheers

[Groggy]

quote:Originally posted by GregP

Hi ChrisMcD,

The British pumps were Turbochargers. In WWII, the term was Turbosupercharger. Later, it was shortened to Turbocharger.

Turbochargers are better than superchargers for engines that operate at a fairly constant RPM. They are less suited to racing automobiles that need power RIGHT NOW in the middle of a corner.

Aviation was a perfect application for them.


problem sorry post later

[Groggy]

quote:Originally posted by ChrisMcD

Just to add some points

1) British Superchargers - Rolls Royce, in particular, prefered to use the exhaust gasses for extra thrust. I cannot remember the exact details, but it was about 400 lbs of thrust which became very significant at higher speeds when the efficiency of propellors dropped off.

I agree with the comments about GE superchargers taking time to get into full production. You pick up comments about both the P40 and the early P51's (Apaches?) suffering from the lack of them. One theory about the useless Brit P38's was that the US was reluctant to risk letting the Germans get a look at their turbocharger technology. It makes more sense than most, when you consider that the P38 was supposed to be a fast climbing, high altitude interceptor that would obviously be crippled without the turbochargers that were so basic to it's design. A seconday theory is that Arnold got the UK Purchasing Commission to order P38's so that Lockheed could get large scale production lines planned without having to go thru Congress.

2) Quality of production. There was a big debate in 1940 when it was discovered that rebuilt Hurricanes were some 30 mph slower than new builds. Expected problems from the 'shadow' factories were only really evident on engines, where there were a number of quality control problems with batches from car manufacturers early on.

3) As I understand it Russian aluminium production took a while to build up and was not helped by the Germans taking out a lot of hydroelectic plants. So it was wood or nothing in the early war years. When things got better a number of planes were redesigned in metail (ie Lagg 7 to 9).

4) Russian engine development lagged (sorry) a bit in the early years of the war, so there was a tendency to keep structural weights low and to do a lot of work on wood/bakelite composites (ie Lagg 3). They had good metalurgy and did a great work of catching up. As I understand it the Russian copies of the Nene had better metals than the Rolls Royce ones.

5) Japanes engines appear to have been the ones most troubled by quality problems. The Nakajima Homare was a very compact design and later production models had a lot of problems. They also had a lot of problems with the lubrication of the DB 601 copies.


Pof. John Allen said that when he was at Farnborough he found through very careful tests that a hurrican At 30000feet the exhaust thrust provided half the thrust half from the airscrew. which surprised me, I will ask him again at the weekend.

[Kutscha]

Mark, how can you say 'low fuel rating'? German C3 was equivelent to Allied 100/150 PN fuel while B4 was equivelent to Allied 100PN. The Germans used the bottom of the 'rich/lean' while the Allies used the top of the 'rich/lean' for fuel rating.

The DB60x engines used higer CRs than Allied engines. The Merlin/Griffon engines had 6.0:1 while the DBs had up to 8.5/8.3:1 CRs (one bank at 8.5, the other at 8.3).
http://www.axiomdigital.com/db605.htm

[ChrisMcD]

Hi Groggy,

Yeah I know terms change - but you know what I meant.

What I find interesting is the way the Brits (particularly Rolls Royce) were determined not to use exhaust gases to power superchargers. Is this special pleading after the facts, or was exhaust thrust really worth having.

After all, Rolls developed centrifugal jets by scaling up supercharger compressors. So why could they have not used experience of hot section turbines to quickly develop turbosuperchargers for the Griffons that ended up in the Shakletons.

Remember the Napier Nomad, which was intended to go into the Shakleton, was suposed to have a turbosupercharger. Also, if I remember correctly Rolls had to license a mechanical supercharger drive from Farman (or Hispano Suiza) so it was hardly a case of 'not invented here'!

[Trexx]

It is fascinating that racing planes and some military ones just before World War Two, had flush exhaust ports. Streamlining was applied to their construction as anything that could be kept out of the slipstream was. (ie: Supermarine SB6 and Hurricane prototypes too)

Then, shortly thereafter, especially on the Spitfire and the Hurricane, the purposely bent-back exhaust tubes are all of a sudden very conspicuous. This untapped thrust source must of been considered very much worth exploiting. The percentage of thrust figures stated earlier, seem exaggerated however. But I've heard things such as an extra five to ten miles per hour (depending on atmosphere density) was derived from piston exhaust, and even more when water injection was applied.

[Mark J]

Kutscha
Thanks for the link, very interesting. They did alright on 97 octane and even better with water injection.
OK, I stand corrected :)

cheers

[DoBravery]

Did the German's use forced labor in the aircraft industry as they did in such programs V-1, V-2?

I couldn't imagine quality being great under those conditions.

[Kutscha]

Yes. Willie went to jail because he used forced labour.

[Trexx]

quote:Originally posted by DoBravery

Did the German's use forced labor in the aircraft industry as they did in such programs V-1, V-2?

I couldn't imagine quality being great under those conditions.


The Bacham Natter interceptor was especially designed to be built by a 'slave type' work force by having many components easily roughed together to be subsequently finished and married up with more 'sensitive' parts by higher skilled laborers (loyal to the Reich).

The same techniques were also used on the He-162.

[Groggy]

quote:Originally posted by Trexx

It is fascinating that racing planes and some military ones just before World War Two, had flush exhaust ports. Streamlining was applied to their construction as anything that could be kept out of the slipstream was. (ie: Supermarine SB6 and Hurricane prototypes too)

Then, shortly thereafter, especially on the Spitfire and the Hurricane, the purposely bent-back exhaust tubes are all of a sudden very conspicuous. This untapped thrust source must of been considered very much worth exploiting. The percentage of thrust figures stated earlier, seem exaggerated however. But I've heard things such as an extra five to ten miles per hour (depending on atmosphere density) was derived from piston exhaust, and even more when water injection was applied.


Hi Trexx,

I would have agreed with what you have written, So was very surprised when told the figure for the Hurricane at 30000ft was 50% thrust from the exhaust. The investigation was done in 1942 at Farnborough by the gentleman who gave me the figures. We met again at the weekend and he confirmed the figures.
The explanation given in part was the altitude, the decrease in the speed of sound meant that the airscrew was now in a regime were compressibility was a more significant factor and decreased the thrust accordingly.
While conversely the jet component increased because of the reduced atmosphere.
Look at the difference in thrust between seal level and a vacuum for rocket motor.
There were other factors but I did not understand completely the explanation.

This was a rigorous investigation and the results helped confirm the British intent to convert to jets as soon as practicable.
Can some please give a value for the speed of sound at sea level and at 30000 feet? I am guessing a difference of about a hundred mile an hour.

Another aside, the RR Clyde was ground tested before its cancellation at power out puts which were to have given the operational Westland Wyvern a speed of 500 mph at sea level.
I remember reading of a maximum figure of 520 mph at an unspecified altitude for this aircraft engine combination. This must have been at the limits for prop driven aircraft.

[curmudgeon]

This has become a fascinating topic, but it will never be found under its current heading ...

[Romantic Technofreak]

The deterioration of the German fighter quality around 1944/45 depends on the fact that quality was traded for quantity. When Albert Speer took over the supervision of the German armament production, he did everything to increase the output in numbers. Mostly this was done by the use of armies of slave workers, which were not only hungry and unmotivated, but also unskilled. So, in result, assembled parts often did not really fit (this could be easily compared to captured Allied fighters), and engines often did not return their announced power and endurance.

The German engines, especially the DB 60X ones, were generally some size bigger than their British counterpart, the RR Merlin, for to deliver the approximately same performance. As much as I know, this is due to the fact that Germany did not have the same amount of high-temperature-stable materials to use. The German engines were bigger, heavier, thus making the aircrafts heavier, thus pressuring to keep the wing area small for to save weight, thus hampering the aircraft´s maneuverability... you see what I mean...!