FW-190A8 Speed Chart

[Legioneod]

I've been working on a speed chart for different aircraft in order to compare their performance at different altitudes, the problem that I am having is converting IAS to TAS accurately.

 

I've been using two methods to convert my data, TacView and a IAS-TAS Calculator:

https://www.dauntless-soft.com/products/Freebies/TrueAirspeedCalculator/

 

The problem is they are giving me two completely different results, and neither one really matches historical charts.

 

TacView seems to be close to what I experienced in-game but at certain altitudes it gives me very odd (and I assume, incorrect) results.

The Calculator gives me numbers way above any historical charts I have ever seen.

 

What would be the best way to get more accurate data?

 

Here is my test results so far(keep in mind none of this is finished and I will probably run the test multiple times.)

Units are MPH and Ft.

.

 

Here is a graph to better visualize my results. (I know it's kinda crappy, I really dont know how to use excel so I just made this quickly in Photoshop)

Edited September 16, 2018 by Legioneod

[AndyJWest]

Where are you getting the temperature data for the TAS calculator from? 

[Legioneod]

6 minutes ago, AndyJWest said:

Where are you getting the temperature data for the TAS calculator from? 

The game, I just opened up the map in the mission editor and looked at the temps.

If I knew what the temps were at each altitude I'd have more accurate results I think.

Edited September 16, 2018 by Legioneod

[AndyJWest]

The mission editor only shows the temperature at ground level. You need to allow for the lapse rate: typically around -2° C per 1,000 ft. This will bring the two results a lot closer.

[Legioneod]

8 minutes ago, AndyJWest said:

The mission editor only shows the temperature at ground level. You need to allow for the lapse rate: typically around -2° C per 1,000 ft. This will bring the two results a lot closer.

Thought about doing that, I'll try it and see.

 

I'm curious why TacView doesnt show more accurate results.

 

EDIT: Found this, gonna plug in the data and see what I come up with.

http://meteorologytraining.tpub.com/14269/css/14269_75.htm

Edited September 16, 2018 by Legioneod

[-=PHX=-SuperEtendard]

I use this website http://indoavis.co.id/main/tas.html  and the temperature data I measured it with the Pe-2 and Bf 110. I compared the settings I use with a German test that listed both IAS and TAS, and the TAS results I calculated from the reported IAS were very close to the real TAS (1-2 km/h difference in most cases).

I tested the A-8 with full fuel and 50% shutters and got this:

[HandyNasty]

http://www.newbyte.co.il/calc.html

My tests in meters and kph of 190A-8 TAS give me for combat mode / boosted mode (with 50% percent rads*). I used the link above for cas to tas conversion. i mainly use this link for rough estimation, keeping in mind it might have some error margin

 

 

I seem to roughly find same values as SuperEtendard.

 

* On deck I find a difference of 34 kph between full open rads and fully closed rads on boosted mode (aka : 560kp vs 594kph). Which is why i want the engine thermodynamics of the A8 revisited.

 

 

Edited September 16, 2018 by =FSB=HandyNasty

[PainGod85]

1 hour ago, =FSB=HandyNasty said:

http://www.newbyte.co.il/calc.html

My tests in meters and kph of 190A-8 TAS give me for combat mode / boosted mode (with 50% percent rads*). I used the link above for cas to tas conversion. i mainly use this link for rough estimation, keeping in mind it might have some error margin

 

 

I seem to roughly find same values as SuperEtendard.

 

* On deck I find a difference of 34 kph between full open rads and fully closed rads on boosted mode (aka : 560kp vs 594kph). Which is why i want the engine thermodynamics of the A8 revisited.

 

 

 

Emphasis mine.

 

What. The. Actual. F...

 

No way the radiator flaps should increase drag this much.

[Ehret]

Just now, PainGod85 said:

No way the radiator flaps should increase drag this much.

 

No way? The La-5 has 36km/h and the P-39 40km/h differences between 0-100% cowl/flush rads @ SL @ full boosts. Other planes are probably similar.

Edited September 16, 2018 by Ehret

[Finkeren]

8 hours ago, PainGod85 said:

 

Emphasis mine.

 

What. The. Actual. F...

 

No way the radiator flaps should increase drag this much.

 

The flaps themselves only account for a small fraction of the total increase in drag. Most of it is caused by the increased airflow over the engine and through the cooling system. 

 

 

[HandyNasty]

8 hours ago, PainGod85 said:

Emphasis mine.

 

What. The. Actual. F...

 

No way the radiator flaps should increase drag this much.

 

my tests show me similar results for other planes. Not claiming here my tests are 100% accurate

 

Difference between max rads and fully closed rads for : 

- 109F-4 boosted mode on deck : 501/549 kph (48kph diff)

- La5 Boosted mode on deck, outlet effects only : 513/548kph (35kph diff)

- yak1B on deck : 506/544 (38kph diff)

- P-39* on deck, boosted mode : 534/574kph (40kph diff)

- Mig3 on deck, boosted mode : 493/536ph (43kph diff)

- Mc202 on deck, boosted mode : 499/517kph (18kph diff)

- SpitVb on deck boosted mode, engine merlin 45 : 521/538 (17kph diff)

 

Seems the 34kph difference for the A8 are not extreme, considering the results of my tests. Then again, I know nothing of drag induced by flaps or airflow through rads.

 

 

* difference between max rads and 60%/45% for water/oil, aka flush setting

 

 

[Legioneod]

11 minutes ago, =FSB=HandyNasty said:

 

my tests show me similar results for other planes. Not claiming here my tests are 100% accurate

 

Difference between max rads and fully closed rads for : 

- 109F-4 boosted mode on deck : 501/549 kph (48kph diff)

- La5 Boosted mode on deck, outlet effects only : 513/548kph (35kph diff)

- yak1B on deck : 506/544 (38kph diff)

- P-39* on deck, boosted mode : 534/574kph (40kph diff)

- Mig3 on deck, boosted mode : 493/536ph (43kph diff)

- Mc202 on deck, boosted mode : 499/517kph (18kph diff)

- SpitVb on deck boosted mode, engine merlin 45 : 521/538 (17kph diff)

 

Seems the 34kph difference for the A8 are not extreme, considering the results of my tests. Then again, I know nothing of drag induced by flaps or airflow through rads.

 

 

* difference between max rads and 60%/45% for water/oil, aka flush setting

 

 

 

Ran another test today but only got a 29kph difference between fully open and fully closed 558/587. I've also never been able to go any faster than 587 on the deck.

[kramer]

La-5 shutters are like huge airbrakes, similar to modern fighters, FW190 has tiny shutters. The shutters of FW190 are far too small to influence the drag significantly but they can disturb the airflow - but only to the point of A-3 without shutters at all.

La-5 and especially La-5FN's engine themperature model looks far, far too optimistic - La-5FN can fly 10 min full boost / max RPM with both oil radiator and shutters completely closed, in the hottest enviroment, without any consequences with engine being still cold. In real La-5FN manual Forsazh was restricted due to thermal reasons... A-8 in similar settings will boil in 30-60 seconds.

 

FW190A-3 and A-5 looks believable.

FW190A-8 - far too pesimistic, it's far hotter in every conditions than A-5. With the same engine and the same cooling system in every identical circumstances.

 

It's possible Fw190A-8 has some new mechanics and La-5FN some old system, very save, very conservative when you practically can't overheat the engine, even with all radiators fully closed in the hottest enviroment.

Who knows, we will see what the next patch with reworked A-8 will present. Developers know about all that for sure.

Edited September 17, 2018 by kramer

[Finkeren]

As already said: The size of the shutters/cowl flaps doesn’t matter that much. The real kicker is the increased airflow through the aircraft. 

[PainGod85]

26 minutes ago, Finkeren said:

As already said: The size of the shutters/cowl flaps doesn’t matter that much. The real kicker is the increased airflow through the aircraft. 

 

You are aware this is literally saying airflow inside a computer case fitted with just one intake fan decreases if you cut a few more holes into the side opposite of said fan, yes?

[AndyJWest]

43 minutes ago, PainGod85 said:

 

You are aware this is literally saying airflow inside a computer case fitted with just one intake fan decreases if you cut a few more holes into the side opposite of said fan, yes?

 

No, it isn't 'literally' saying anything of the sort. 

[Finkeren]

1 hour ago, PainGod85 said:

 

You are aware this is literally saying airflow inside a computer case fitted with just one intake fan decreases if you cut a few more holes into the side opposite of said fan, yes?

 

No I'm not saying anything of the sort. In fact, I'm kinda saying the opposite (though not really either) The reason cowl flaps/shutters exist is to control the airflow over the engine or through the radiator system. The more you open these flaps, the greater the airflow. This airflow causes drag, quite a lot of it in fact, since a radial engine block or the inside of a liquid cooling system is pretty draggy compared to the smooth outer surface of the aircraft. It is this drag that contributes the majority of the drag increase, when cowl flaps/shutters are opened, not the flaps themselves. Hence it doesn't really matter how small and insignificant the cowl flaps on the Fw 190 look compared to, say, the La-5, because that's not what creates most of the drag.

Edited September 17, 2018 by Finkeren

[kramer]

They definitely create significant drag if they have significant surface. Even Fw190A-3 with holes permanently opened and full airflow is faster than Fw190A-5 with small shutters fully opened. 

[Finkeren]

12 minutes ago, kramer said:

They definitely create significant drag if they have significant surface. Even Fw190A-3 with holes permanently opened and full airflow is faster than Fw190A-5 with small shutters fully opened. 

 

I’m not saying the drag created by the flaps/shutters is insignificant, just that it is smaller than the drag caused by the airflow through the engine/cooling system.

[HandyNasty]

9 hours ago, Legioneod said:

Ran another test today but only got a 29kph difference between fully open and fully closed 558/587. I've also never been able to go any faster than 587 on the deck.

I actually managed to get 596kph right now on Kuban autumn map, height above sealevel 50 meters, fully closed rads, fully loaded. Speed from ingame instrument panel and not cockpit reading . So I presume is CAS (and not IAS).

Engine died like 10 seconds after reaching 596kph.

[JtD]

2 hours ago, Finkeren said:

I’m not saying the drag created by the flaps/shutters is insignificant

 

If you're not saying it, then I am.

 

In fact, a properly designed outlet flap can reduce drag when compared to just a flapless hole in the side (same airflow assumed).

[Finkeren]

5 minutes ago, JtD said:

 

In fact, a properly designed outlet flap can reduce drag when compared to just a flapless hole in the side (same airflow assumed).

 

Perhaps, but flaps like ones on the La-5 certainly can’t be completely insignificant drag-wise. Yet, obviously it pales in comparison to the drag cause by the airflow over the engine and through the cooling system.

[PainGod85]

4 hours ago, Finkeren said:

 

No I'm not saying anything of the sort. In fact, I'm kinda saying the opposite (though not really either) The reason cowl flaps/shutters exist is to control the airflow over the engine or through the radiator system. The more you open these flaps, the greater the airflow. This airflow causes drag, quite a lot of it in fact, since a radial engine block or the inside of a liquid cooling system is pretty draggy compared to the smooth outer surface of the aircraft. It is this drag that contributes the majority of the drag increase, when cowl flaps/shutters are opened, not the flaps themselves. Hence it doesn't really matter how small and insignificant the cowl flaps on the Fw 190 look compared to, say, the La-5, because that's not what creates most of the drag.

 

3 hours ago, Finkeren said:

 

I’m not saying the drag created by the flaps/shutters is insignificant, just that it is smaller than the drag caused by the airflow through the engine/cooling system.

 

Your increase in drag isn't produced inside the engine cowling. You cannot possibly increase effective drag by opening or widening a hole behind a fan, just as you cannot stem flooding by enlarging the hole made in a levee.

 

Instead, the increase in drag on the 190 is caused by turbulence induced by the air exiting the engine compartment. This is mirrored by the RL results on the A-4 airframe, which - in its earliest iterations - still had the A-3's gills instead of cooling flaps.

 

http://www.wwiiaircraftperformance.org/fw190/fw190-619-nr2.html

http://www.wwiiaircraftperformance.org/fw190/fw190-619-nr3.html

 

Nr 2 is for reference stating the plane has gills, Nr 3 is the actual test.

 

http://www.wwiiaircraftperformance.org/fw190/fw190-665-nr3.html

 

The clean plane with gills and no MG FF belt hatches is 18 kph slower than the plane with split flaps completely closed and said belt hatches.

 

E: Also, I want to gouge out my eyes. 

 

http://www.wwiiaircraftperformance.org/fw190/fw190a4.html

 

Fw 190 flight tests, or: "Let's arbitrarily change plane conditions so we cannot directly attribute performance changes to any one modification we made."

Someone shoot those engineers.

Edited September 17, 2018 by PainGod85

[AndyJWest]

17 minutes ago, PainGod85 said:

...You cannot possibly increase effective drag by opening or widening a hole behind a fan, just as you cannot stem flooding by enlarging the hole made in a levee...

 

False analogy. The 'airflow behind the fan' (or in this case propeller) has two alternative routes: through the cowling, or around it. It is entirely possible that permitting more  of the airflow to pass through the cowling (and around all the obstructions in it) will result in more drag than restricting the airflow through it. Indeed, the reason engine cowls are fitted in the first place is to reduce drag.

[=362nd_FS=RoflSeal]

The only real information on the outlet cowls on the FW-190 is from the A-4 where they were first introduced in the middle of production. Either way, it doesn't matter for the A-5/A-8 considering the engine is the same and produces the same power.

 

http://www.wwiiaircraftperformance.org/fw190/fw190-711-nr2.html

 

 

The results: t_zyl = 255 / 260° for climb with combat power and split flaps closed, and t_zyl = 220° with flaps fully open, showed good agreement with the measured temperatures of 0028 (Comparison report: "Fw 190 with split flaps from 9.6.42 "). Level flight values were determined at 1,640 feet (500 meters) with t_zyl max = 180° or 175° and at 26,247 feet (8000 meters) with t_zyl max = 200° or 190° for split flaps "closed" or "open". This shows that the cooling effect of the split flaps in level flight is minor but increases somewhat with increasing height. This fact is, however, not relevant, since the split flaps remain closed in level flight at all altitudes, even in the tropics.

 

http://www.wwiiaircraftperformance.org/fw190/fw190-665-nr3.html

 

	The speed loss with the split flaps fully open at this power is 22 – 25 mph (35 – 40 km/h). It should be noted that the aircraft is slower by ~6 mph (10 km/h) compared to Serial Nr. 711, also equipped with split flaps.  Special attention must be paid to the split flaps actuator set up under 40 kg pre-load, since the pre-load decreases with time and then the flaps stand open in level flight.
2.)	Climb rate (Graph No. 2) could be flown only with split flaps open, otherwise the maximum cylinder temperatures would have been exceeded under the currently prevailing outside air temperatures. The service ceiling with closed split flaps was therefore determined by considering the known rate of climb loss with open flaps (~ 1.5 m / sec).

 

This makes clear that the split flaps are only for slow flight/climbing flight, they have little effect on cooling in high speed flight. Ingame, the A-5 and A-8 overheat if the flaps are closed.

 

For the A-5 running tested with the 1.58/1.65 ata boost that would be introduced in the A-8

http://www.wwiiaircraftperformance.org/fw190/BMW-VB-126.html

 

Level Flight

Cylinder head temperatures:

Head temperatures were measured at the cylinders 8, 9, 11 and 12, where temperatures on cylinder 8 were lowest and on cylinder 9 were highest. In full throttle altitude second supercharger gear the highest temperatures result, which on the hottest cylinder for summer would be 216°C and for the tropics would be 226°C and would pose no threat for the short flight duration.   Climb   The cylinder head temperature was increased by 13°C on the hottest cylinder compared to normal combat power and was 211°C in 6 km altitude, where outside air temperature was equal to summer conditions, so that for tropical conditions 221°C result. The flight speed was Va = 265-270 km/h and the cooling flaps were opened to "position 3".

 

And just for extra info the A-9, the aircraft has a slightly different cooling system in regards to the fan.

 

http://www.wwiiaircraftperformance.org/fw190/fw190-410230-nr1.html

 

The highest cylinder temperatures were recorded in climbs with combat power and fully opened split flaps at cylinder 1. With the production fan at the reversal altitude of ~ 7000 m a temperature tzyl 1 = 235 ° on the hottest European summer day (cina + 15°) results. The short term temperature limit of  240° is therefore not exceeded. With the oil cooler F 20750 as used up to now the oil intake temperatures into the engine at the temperature reversal height of 8000 - 8500 m have been determined as tÖME = 82° (based on the hottest summer day, cine + 20°). The permissible maximum has been given as 85° also for the F-engine by the manufacturer, so that this cooler meets the requirements in Europe.

Generally the cylinder temperatures measured with closed split flaps in level flight at combat power near sea level are very low. The highest value at the hottest cylinder for a European summer day is only 157°, while all other heads show temperatures between 130 - 145° (see chart 12). Already for European conditions difficulties due to overcooling of the engine can be expected, in particular from the installation of a fan with an even higher flow rate. A further reduction in the outlet cross section in order to reduce air flow is not possible, since, as shown in charts 6 and 13, in climbs under the same conditions the short term temperature limits are almost reached.

 

[Makz]

So Germans tested FW-190s with fully closed split flaps in level flights?

Edited September 20, 2018 by Makz

[CUJO_1970]

On ground, typically = flaps open, in climbing flaps set to "position 3" (~half open) Cylinder head temps with closed flaps were noted as being very low, even at combat power. There was a greater concern for over-cooling, not over-heating.

 

The 10 minute limit at 1.58/1.65ata, seems to be in place for engine parts stress, not over heating. The A-8 we have in the sim uses the 801/TU power egg - distinguished from the earlier 801D2(F-600) it incorporated strengthened parts developed for the 2,400hp 801F that itself never made it to series production.

 

The A-9 used more features from the 801F development that it was given a completely new model designation. The new fan on the A-9 reverted back to the earlier 14-bladed fan IIRC.

[MiloMorai]

You remember correctly CUJO.

[-=PHX=-SuperEtendard]

7 hours ago, Makz said:

So Germans tested FW-190s with fully closed split flaps in level flights?

 

I don't know, there is a chart for a 1.58 ata Fw 190 A-8 showing around 565 km/h at sea level. In game you achieve that speed with 85% open shutters, I don't know which were the conditions of that test (open shutters? center bomb rack? etc).

Edited September 20, 2018 by -=PHX=-SuperEtendard

[Makz]

9 часов назад, -=PHX=-SuperEtendard сказал:

 

I don't know, there is a chart for a 1.58 ata Fw 190 A-8 showing around 565 km/h at sea level. In game you achieve that speed with 85% open shutters, I don't know which were the conditions of that test (open shutters? center bomb rack? etc).

Without ETC (ohne ETC), with moving landing gear flaps (mit beweglichen fahrwerks-klapen), sealing of engine hoods (abgedichtete triebwerksspatte), surface putty (oberflache gespachtelt). Looks like it is good enough preparation for a good speed results. Was it with closed split flaps too?

565 km/h its 1.65ata (see ladedruck 1.58/1.65). At 1.58ata aproximately 544 km/h.

Edited September 21, 2018 by Makz

[=362nd_FS=RoflSeal]

11 hours ago, Makz said:

Without ETC (ohne ETC), with moving landing gear flaps (mit beweglichen fahrwerks-klapen), sealing of engine hoods (abgedichtete triebwerksspatte), surface putty (oberflache gespachtelt). Looks like it is good enough preparation for a good speed results. Was it with closed split flaps too?

565 km/h its 1.65ata (see ladedruck 1.58/1.65). At 1.58ata aproximately 544 km/h.

No, A-8's engine could no develop 1.65 ata in first gear. 1.58/1.65 means 1st gear is 1.58 ata, 2nd gear is 1.65 ata.

 

For some reason that A-8 is a bit slower then other tests

 

http://www.wwiiaircraftperformance.org/fw190/Fw_190_A-8_15-3-44.pdf

 

 

At SL:

Around 555kph at 1.42ata, and 578kph at 1.58ata

 

[MiloMorai]

Fw190A-8 Hand book with flight data, https://issuu.com/joete6/docs/pilot_manual_-_flugzeug-handbuch_-_

[Makz]

11 часов назад, RoflSeal сказал:

No, A-8's engine could no develop 1.65 ata in first gear. 1.58/1.65 means 1st gear is 1.58 ata, 2nd gear is 1.65 ata.

Thanks! My mistake.