Top SL speed

[Hummingbird]

Like I said the performance with the new prop 9-129 (aka Dünblatt) was calculated, but there's litterally zero reason to believe the performance illustrated with the series prop is, as the aircraft had long since gone operational by then.

 

Also the real life performance with the series prop would be needed in order to accurately estimate any improvement with the new prop.

[iFoxRomeo]

Like I said the performance with the new prop 9-129 (aka Dünblatt) was calculated, but there's litterally zero reason to believe the performance illustrated with the series prop is, as the aircraft had long since gone operational by then.

 

Also the real life performance with the series prop would be needed in order to accurately estimate any improvement with the new prop.

 

Did you read the second marking: The calculations show...

 

These sheets on kurfurst.org are calculations. Full stop. It doesn't matter if they did flight test or not(Aspera Gmbh performed flighttest). We don't have these tests available and there is no indication, that the test values are incorporated into these calculations sheets; otherwise it needs to be stated in the sheets or the supplemented papers to these sheets, that some of the performance curves are measurements and some are calculations. But that is not the case.

Assumptions don't help here.

 

And why are flight measurements needed for a calculation of the new propeller performance? Its still a calculation, "just" with new variables for the propeller; the "calculated airframe" remains the same.

 

Quote from kurfurst.org: Actual flight test trials with the ... Dünnblattschraube ... showing improvements in good agreement with the Messerschmitt Projektbüro report.

 

But kurfurst.org doesn't provide the test trials.

 

If you can show a sheet that is named "Flugversuch" then the situation changes. But "Projektbüro" is quite obviously not a evaluation center. E.g. a paper from E-Stelle Rechlin would be a official evaluation.

 

Fox

[Hummingbird]

Sorry but suggesting the R&D department is shut off from the world just isn't credible, they would naturally use real life test results to compare with, calculate & verify performance with improvements to parts.

 

To suggest that they were using calculated performance curves for an aircraft that had by then been in active combat for over 3 months is absurd to say the least. There can be little doubt they had long since established the performance of the series aircraft at that point, and to use anything but real life performance in comparison with a calculation of projected performance with a new part is ridiculous, period.

[iFoxRomeo]

Sorry but suggesting the R&D department is shut off from the world just isn't credible, they would naturally use real life test results to compare with, calculate & verify performance with improvements to parts.

 

To suggest that they were using calculated performance curves for an aircraft that had by then been in active combat for over 3 months is absurd to say the least. There can be little doubt they had long since established the performance of the series aircraft at that point, and to use anything but real life performance in comparison with a calculation of projected performance with a new part is ridiculous, period.

 

Well, in this case assumptions are what I call absurd. No use in further discussing with you, because you refuse to read and accept what the source states and prefer your assumptions instead. You are only interested in enforcing your position based on your assumptions. Facts are of no interest for you.

 

I don't think you will read this. You will especially ignore the notes. But nevertheless...

 

Everything from kurfurst.org

 

Original in german:

 

 

And translated in english:

 

 

 

 

Have fun, bye bye.

[Yo-Yo]

Just one note - Mach effect WERE NOT TAKEN IN ACCOUNT...

[grafspee]

Just one note - Mach effect WERE NOT TAKEN IN ACCOUNT...

 

Yes, this thing when you reduce engine rpm, and suddenly you get in to much higher speeds.

We just need to change gear ratio of propeler reduction gear box and K-4 will hit +600km/h at SL

Wonder why all the warbirds didn't got their reduction gear boxes changed, because all of them perform much better at reduced rpm.Now combine this reduced prop rpm with ability for engine to stay in max power settings, effect will be even bigger.

Edited August 29, 2020 by grafspee

[Yo-Yo]

Yes, this thing when you reduce engine rpm, and suddenly you get in to much higher speeds.

We just need to change gear ratio of propeler reduction gear box and K-4 will hit +600km/h at SL

Wonder why all the warbirds didn't got their reduction gear boxes changed, because all of them perform much better at reduced rpm.Now combine this reduced prop rpm with ability for engine to stay in max power settings, effect will be even bigger.

You do not take in account that reducing prop rpm ruins overall thrust, including high speed region.

[grafspee]

You do not take in account that reducing prop rpm ruins overall thrust, including high speed region.

 

I don't know, so why in DCS when i reduce rpm plane fly faster despite the fact that engine producing less power. ?? Isn't it improving high speed region ?? by reducing prop rpm ??

Just immagine how fast K-4 would be flying if gear ratio would be possible to change. Just drop prop rpm a little and remain engine rpm. 620kph would be possible.

[amazingme]

Well, in this case assumptions are what I call absurd. No use in further discussing with you, because you refuse to read and accept what the source states and prefer your assumptions instead. You are only interested in enforcing your position based on your assumptions. Facts are of no interest for you.

 

I don't think you will read this. You will especially ignore the notes. But nevertheless...

 

Everything from kurfurst.org

 

Original in german:

 

 

And translated in english:

 

 

 

 

Have fun, bye bye.

 

Hummingbird's reasoning is perfectly justifiable, just as Yo-Yo's extrapolations are when he calculated different things for all birds where data were not available.

 

But, what does this mean? "This 12 km/h will be only added to the calculations, if the abovementioned MEASURES can be actually materialized for series production." (if that's the correct translation).

[iFoxRomeo]

Hummingbird's reasoning is perfectly justifiable, just as Yo-Yo's extrapolations are when he calculated different things for all birds where data were not available.

..

You are comparing apples with oranges.

 

 

These sheets are caluculations.

 

 

Flight tests and the results look like these:

Source: wwiiaircraftperformance.org

http://www.wwiiaircraftperformance.org/me109/VB-109-11-L-42.pdf

 

 

 

 

Abt. Flugerprobung, Gruppe Leistungen // Versuchsbericht Nr. 109 11 L 42

 

Section: Flighttest, Group: Performance // Testreport Nr. 109 11 L 42

 

 

 

 

Testflights include the aircraft registration, serial number, engine number, date of flight, pilots name etc.

 

None of these information are mentioned in the other sheets. No reference to a testflight.

 

 

Is it really so hard to understand that? Calculation is mentioned in the preliminary note multiple times, yet it is simply ignored.

 

 

...But, what does this mean? "This 12 km/h will be only added to the calculations, if the abovementioned MEASURES can be actually materialized for series production." (if that's the correct translation).

Measures -> actions, arrangements, steps

 

 

 

Fox

[amazingme]

You are comparing apples with oranges.

 

 

These sheets are caluculations.

 

 

Flight tests and the results look like these:

Source: wwiiaircraftperformance.org

http://www.wwiiaircraftperformance.org/me109/VB-109-11-L-42.pdf

 

 

 

 

Abt. Flugerprobung, Gruppe Leistungen // Versuchsbericht Nr. 109 11 L 42

 

Section: Flighttest, Group: Performance // Testreport Nr. 109 11 L 42

 

 

 

 

Testflights include the aircraft registration, serial number, engine number, date of flight, pilots name etc.

 

None of these information are mentioned in the other sheets. No reference to a testflight.

 

 

Is it really so hard to understand that? Calculation is mentioned in the preliminary note multiple times, yet it is simply ignored.

 

 

 

Measures -> actions, arrangements, steps

 

 

 

Fox

 

If you read carefully the document, it says that "The stated performance figures are going to be reached with well-built serial production machines FOR CERTAIN." No specials were included in the calculations: as in surface finish of airframe and prop, or improved rads and so on. Also, the documents that you provided are clearly incomplete.

Nevertheless, I would trust those engineers more than I trust you or anyone else that didn't took part in the development.

[iFoxRomeo]

If you read carefully the document, it says that "The stated performance figures are going to be reached with well-built serial production machines FOR CERTAIN." No specials were included in the calculations: as in surface finish of airframe and prop, or improved rads and so on. Also, the documents that you provided are clearly incomplete.

Nevertheless, I would trust those engineers more than I trust you or anyone else that didn't took part in the development.

 

Lol. Are you unable to open the provided link? There is the complete document! I just used two excerpts to show exemplary how Messerschmitt engineers structure their "Testflights and corresponding documents". There is no content from me at all, that you can or can not trust.

And I read the documents. I do understand german.

You trust the developers? Then read their documents and try harder to understand them.

The "...for certain" sentence also shows that this document is about calculated performance of the K4 and K6, not measured performance. That is what the fuss is all about.

 

Fox