Official Fulqrum Publishing forum - Speed graphs for Spitfire and Hurricane

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- - Speed graphs for Spitfire and Hurricane (http://forum.fulqrumpublishing.com/showthread.php?t=31450)

Quote:

Originally Posted by Osprey (Post 414682)

I removed the BS so we can be clear about your position.

lmfao

i was gonna write that

is there a performance chart like the ones BS posted for the IIa?

all this arguments and the spit IIa may become the "default" red fighter for a more even fight on most servers?

until they pork that one too.

Quote:

Originally Posted by Kwiatek (Post 414936)

I translated there is not information about confirmed lower power output but only about correct mainfold pressure, temperature and not guarantee engine power - nothing more. No info about lower power output.

Ok, so we have established that your tests were not corrected for nominal engine outputs, and therefore, irrevelant as we do not know what powers were developed during the tests.

Hint: We know exactly in the case

Quote:

Exacly that why it looks that V15 prototype didnt used variable hydraulic supercharget but only 2 position one. With variable supercharger speed polars will be much more smooth.

Problem is, you do not seem to understand how the hydraulic coupling the DB 601 works. It has two oil pumps, one constant supply (fixed speed, MS, thats the first "straight" line up to around 2000 m in the power curves), one variable supply to set the amount of slip (speed of supercharger) via oil pressure. You can set the second one for full oil delivery, and voila, it operates exactly like a fixed speed supercharger with two fixed ratio gears.

Quote:

Please - Your own site:

http://kurfurst.org/Performance_test...w_109V15a.html

" It appears that variable-speed hydraulic supercharger control was either not present or not engaged in the tests (ie. testing seperately with both supercharger gears) : low-altitude and high-altitude supercharger speeds were engaged at a given boost pressure, therefore the curves do not show the characteristic shape of the DB power curve - this would result in a more smooth,curved transition and improved in performance between the supercharger`s two critical altitudes (ca between 2200 and 4800m) in level flight."

Well you just have to read it now I think... I have bolded it out for ya.

Quote:

Again for prototype V15 and German prospect not FOR SERIAL PRODUCTION plane. Nothing knew. I would like to see such speeds for serial planes.

Again I suggest you read the conditions of the airfame for the V15. Its the same as the serial production airplane.

As for the speeds for serial production planes, it can be read here. 500 km/h at SL.
http://kurfurst.org/Performance_test...chreibung.html

Suorce? I dont see any information about these.

Quote:

As we know serial production 109 E had variable hydraulic supercharger so how and for what would like to disable MS gear????

I do not know. "Disabling" the MS gear is easy - you just have to set the barometric control so that the second oil pump in the hydraulic coupling operates at maximum delivery, and voila, the hydralic coupling operates now at minimum slip and maximum supercharger speed.

As noted, G-6 tested at Rechlin shows the same. I suppose more accurate figures can be collected.

Quote:

Maby Germans, Frenchs, Swiss and Americans made phone call and decided to blocked MS gear in their 109 for test?

The French definietely did not, but they got similar results to the V15 trials.

The rest is plainly in the files. Both V15 trial and the US trial show that they tested both in MS and FS gear. The Swiss is a bit of a guesswork, but then explain me:

a) Why did the Swiss get a straight curve instead of a curved one, ie. a characteristic feature of the DB's barometric control, *when engaged*
b) Why did the Swiss get a result exactly like the Germans in V15 trials while using the Hohenlader (FS gear).

Quote:

Again totally bulshit for me and not confirmed anywhere.

Well again the Swiss tests show exactly the same results as WNr 1774 tests in MS gear. Mere coincidence? I don't think so. No less than 35-40 km/h difference between planes? I do not think so either.

Please translate the text below, then explain how it is different from the "serial production" E-1. Especially the Motorhaube noch roh, Rückstoßer oben unverkleidet part.

An Bf 109 V 15 a, der Mustermachine für die E-1-Serie, wurden die Geschwindigkeitsleistungen erflogen. Aus Zeitmengel konnten nicht die günstigen Rückstoßer
und Ansaughutzen erflogen werden, sodaß evtl. noch Leistungssteigerungen möglich sind.

Zustand des Flugwerkes. Oberfläche : serienmäßiger Anstrich, Motorhaube noch roh, Rückstoßer oben unverkleidet. 2 Flügel- und 2 Hauben-MG eingebaut. Eindrahtantenne. Fahrwehr eingezogen, Sporn außen.

Quote:

Originally Posted by Kurfürst (Post 414858)

What is so 'unhistorical' about it?

According to the graph WEP is available in the game up to FTH, which is not correct. It was only authorized for take-off and up to 1-1.5km. So it's like the other take-off boosts which is shows in G50 or Blenheim graph, they should all only be available at low altitudes.
IIRC the DB601 manual also authorized the use only for overload conditions and short runways, not for regular take-off.

@Buchon,

Quote:

Originally Posted by Kwiatek (Post 414944)

Beacuse it show maximum speed for Spitfire MK1 which mean for 87 octan - +6 1/2 mainfold pressure (boost) - so not red but blue line from RAE charts.

Red line is for maxium continous weak mixture power which mean +2 1/2 mainfold pressure ( boost) for economical flying.

^this.

@Kurfurst, still waiting for your proof that all MKII's were limited to 9lbs from my post earlier,

Quote:

Originally Posted by Kurfürst (Post 414858)

. The Spit II I am afraid is correct, the type was limited to +9 lbs during the BoB, even with 100 octane

I am genuinely intrigued by this, and not messing around, on what is that based?

I've seen this obviously, dated july 1940

http://www.spitfireperformance.com/spit2pnfs3.jpg

and as Crump has pointed out in the other thread that all Spit MkII's were using 100 octane fuel in June 1940.

So what have you got that proves they were only on 9Lbs boost during BoB?

Quote:

Originally Posted by Buchon (Post 414927)

As I said you are comparing a base performance line and Boosted performance line,which is wrong.

Here a really good graph posted by Kwiatek where we can see a base performance line and Boost performance lines, pls watch it :

http://www.spitfireperformance.com/s...-rae-12lbs.jpg

The red line is base performance line, without Boost, I know that is max weak mix and calculated but its a good reference, the real speed should be a slight better then.

So we have a 246mph of sea level without Boost and 283mph with Boost.

Now we can extrapolate that data to the graph made by Klem which contain the B6 data :

http://img842.imageshack.us/img842/9...performanc.jpg

Obviously he is comparing base performance line with Boost line but that don't mean that its not a interesting graph because we have here the sea level speed of the base performance line posted by B6.

As you can see the B6 graph data shows a sea level speed of 255mph without Boost, considering that the 246mph mark of Kwiatek graph is weak mix calculated I can say that it´s pretty accurate.

So, what is wrong with the B6 graph ?

I can say nothing but we need the freaking Boost modeled :!:

I'm not sure who is misunderstanding who but all the curves on the chart I posted, excluding the curve I overlaid from B6's data, are original data from tests made at the time and the first line (lowest speeds in pale blue) are for the boost at +6 1/4lbs Merlin III with 87 octane and a three bladed constant speed propeller. The higher boost curve at +12lbs with 100 octane is the next one listed and in a deeper blue.

My curve takes B6s data (orange line, which only went down to 3000m), projected down to 0 feet (yellow line). The projection may turn out to be not strictly accurate but is a fair basis for the question.

If you look at Kwiatek's chart you will see along the line that starts at 283mph @ 0 feet the words +6 1/4 lbs boost, i.e. the max with 87 octane. The red line is when running 'Max Weak mix' which would of course yield less power and the boost pressure is not given but the pilots notes state that at the weakest setting the max permitted are +2 1/4lbs boost and 2.600 rpm. These are probably the settings reptresented by the red line.

Quote:

Originally Posted by 41Sqn_Banks (Post 414951)

I know an easy fix for that, since the graph WEP shows performance which was achiveable without WEP in real life, simply rewrite the WEP line to Nominal in the FM.

Then add a new WEP line in the FM which is only useable for 1 min / ca 1.5 km and boost performance even further.

Things would be perffect then, and very historical. :D ;)

Quote:

IIRC the DB601 manual also authorized the use only for overload conditions and short runways, not for regular take-off.

I don't remember seeing such restriction. It would be strange in the DB manual anyways.

Quote:

Originally Posted by Kwiatek (Post 414944)

http://i45.tinypic.com/35be654.png

I have to say this again?

There no Boost performance modeled in the game, that´s why its in the Bugtraker, they are working to implement this.

The graph that B6 posted contain no Boost :

http://i47.tinypic.com/2lsw2ux.jpg

That´s why the Patch line is below of the Flight Tests from 3000 to 6000, once the boost is implemented it will raise.

We need the freaking Boost implemented correctly :!:

Quote:

Originally Posted by fruitbat (Post 414957)

@Kurfurst, still waiting for your proof that all MKII's were limited to 9lbs from my post earlier,

I am genuinely intrigued by this, and not messing around, on what is that based?

I have posted this paper (and of course I got it from someone else). But others (I think 41 Banks) have pointed out that this page was amended, given the amendment no, likely in 1941 IIRC. So in short the +12 limit only appears in later manuals, but the 1940 ones.

The unamended (likely first or early) version from July 1940 shows the limit as +9 for 5 min Combat (+12 is enabled, but only for take off for a limited time/altitude).