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XyZspineZyX
11-04-2003, 08:26 AM
Since Skychimp is posting about the P-51's radiator causing no drag or actually increasing thrust/speed (and maybe rightfully so), I wanted to take this ooportunity to make my first and last pitch to Oleg to reduce/eliminate the radiator drag of the 190A.

The 190A used a system of internal mechanisms and controllable gills as part of its cooling system and had no external, drag inducing features. This would really be a significant and, more importantly, proper change to the 190 IMHO. The 190A suffers heavily from radiator drag as it is now and this is very detrimental to the 190A since its main advantage is speed and it often holds only a slight edge.

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"Ice Warriors", by Nicolas Trudgian.



Message Edited on 11/04/03 07:26AM by kyrule2

Message Edited on 11/04/0307:29AM by kyrule2

XyZspineZyX
11-04-2003, 08:26 AM
Since Skychimp is posting about the P-51's radiator causing no drag or actually increasing thrust/speed (and maybe rightfully so), I wanted to take this ooportunity to make my first and last pitch to Oleg to reduce/eliminate the radiator drag of the 190A.

The 190A used a system of internal mechanisms and controllable gills as part of its cooling system and had no external, drag inducing features. This would really be a significant and, more importantly, proper change to the 190 IMHO. The 190A suffers heavily from radiator drag as it is now and this is very detrimental to the 190A since its main advantage is speed and it often holds only a slight edge.

<center>
http://www.brooksart.com/Icewarriors.jpg

"Ice Warriors", by Nicolas Trudgian.



Message Edited on 11/04/03 07:26AM by kyrule2

Message Edited on 11/04/0307:29AM by kyrule2

XyZspineZyX
11-04-2003, 09:04 AM
Just to add a quote:

"The engine oil coolers and induction system are totally enclosed by an extremely neat cowling and cooling is assisted by an engine driven fan behind the propeller."

Again, I believe this significantly detracts from the effectiveness of the 190A as it is unable to sustain its high speeds as it should without overheating or suffering from inaccurate radiator drag.

<center>
http://www.brooksart.com/Icewarriors.jpg

"Ice Warriors", by Nicolas Trudgian.

XyZspineZyX
11-04-2003, 10:42 AM
kyrule2 wrote:
- Since Skychimp is posting about the P-51's radiator
- causing no drag or actually increasing thrust/speed
- (and maybe rightfully so),

Sorry, but Skychimp is wrong in that opinion.
The drag is present anyway for the closed radiator. But in this position the construction of radiator cowling with laminar flow around it really has small drag that allow to get greater speed of the plane itself in comparison with usual radiator cowl placed in that aerodynamically 100% _optimal_ area (like say on Yak-3 or on Yak-9U, that has it in the same place, but hasn't laminar airflow in the place of the P-51D airintake and fuselage. Germans also tried to place there after great experimantal works, but it was too late...You may see it on experimental FWs and Bfs). But when it begins to open - drag will increases anyway.



I wanted to take this
- ooportunity to make my first and last pitch to Oleg
- to reduce/eliminate the radiator drag of the 190A.

Eliminate - it will be not correct from any point of view.
Reduce - I will check if it is there the case. You are wrong about that if it is internal, than it has no drag... It has..., and as more open airflow across the channel - more drag, if to try to explane by simple words.



- The 190A used a system of internal mechanisms and
- controllable gills as part of its cooling system and
- had no external, drag inducing features. This would
- really be a significant and, more importantly,
- proper change to the 190 IMHO. The 190A suffers
- heavily from radiator drag as it is now and this is
- very detrimental to the 190A since its main
- advantage is speed and it often holds only a slight
- edge.
-
- <center>
- http://www.brooksart.com/Icewarriors.jpg
-
- "Ice Warriors", by Nicolas Trudgian.
-
-
-
- Message Edited on 11/04/03 07:26AM by kyrule2
-
- Message Edited on 11/04/03 07:29AM by kyrule2



Oleg Maddox
1C:Maddox Games

XyZspineZyX
11-04-2003, 11:23 AM
S! All,

From my understanding of fluid dynamics, you get best heat exchange from non-laminar flows past hot surfaces, since the boundary layer effect for laminar flows kills conductive energy transfer, leaving only the slower radiative transfer process. So the idea is to get turbulent or near-turbulent flows of incoming cold air near the hot engine parts, thereby boosting conductive heat transfer. Turbulence causes drag, therefore radiator design is a trade-off between drag and cooling efficiency - but there will always be drag from an open radiator.

Now, it makes good sense to design a radiator inlet that minimises drag, because it is always in the airstream, closed or open. But if you want to reduce your engine temperature by air cooling, that means increasing drag, even if only by a little bit!

So I agree with Oleg on the principles, for what it's worth.

Have fun!
IV/JG7_4Shades

XyZspineZyX
11-04-2003, 11:28 AM
That would apply to more planes with radial engines - La7, I16, isn't it?

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XyZspineZyX
11-04-2003, 11:40 AM
S!

Sure, planes with radial engines and open cowls have very turbulent airflow paths, so they have heaps of drag by modern standards. But even planes with small and neat radiator inlets may also have significant drag if the inner airflow path is sufficiently turbulent.

It is all a matter of degree, but you can't get useful cooling without also getting at least some drag.

IV/JG7_4Shades

XyZspineZyX
11-04-2003, 03:35 PM
kyrule2 wrote:
- The 190A used a system of internal mechanisms and
- controllable gills as part of its cooling system and
- had no external, drag inducing features. This would
- really be a significant and, more importantly,
- proper change to the 190 IMHO. The 190A suffers
- heavily from radiator drag as it is now and this is
- very detrimental to the 190A since its main
- advantage is speed and it often holds only a slight
- edge.

I just want to point out that elimination of the external drag inducing parts of the radiator may only cause a slight improvement in drag. It is the flow of the cooling air through the radiator system that causes most of the drag. Just because the air flows internally doesn't mean that it stops producing drag.




Message Edited on 11/04/0304:36PM by Oryx

XyZspineZyX
11-04-2003, 03:44 PM
i wonder if a Pilot of a Fw190 with BMW engine could set the Side "flaps" of his cooling system to automatik with his crank ?

http://www.jagdgeschwader53.flugzeugwerk.net/diverses/franky.gif

XyZspineZyX
11-04-2003, 03:44 PM
You are almost perfectly right /i/smilies/16x16_robot-happy.gif


FourShades wrote:
-
- S! All,
-
- From my understanding of fluid dynamics, you get
- best heat exchange from non-laminar flows past hot
- surfaces, since the boundary layer effect for
- laminar flows kills conductive energy transfer,
- leaving only the slower radiative transfer process.
- So the idea is to get turbulent or near-turbulent
- flows of incoming cold air near the hot engine
- parts, thereby boosting conductive heat transfer.
- Turbulence causes drag, therefore radiator design is
- a trade-off between drag and cooling efficiency -
- but there will always be drag from an open radiator.
-
- Now, it makes good sense to design a radiator inlet
- that minimises drag, because it is always in the
- airstream, closed or open. But if you want to reduce
- your engine temperature by air cooling, that means
- increasing drag, even if only by a little bit!
-
- So I agree with Oleg on the principles, for what
- it's worth.
-
- Have fun!
- IV/JG7_4Shades
-
-
-
-



Oleg Maddox
1C:Maddox Games

XyZspineZyX
11-04-2003, 03:47 PM
Thank you again Very well explained by simple words /i/smilies/16x16_robot-happy.gif


Oryx wrote:
- kyrule2 wrote:
-- The 190A used a system of internal mechanisms and
-- controllable gills as part of its cooling system and
-- had no external, drag inducing features. This would
-- really be a significant and, more importantly,
-- proper change to the 190 IMHO. The 190A suffers
-- heavily from radiator drag as it is now and this is
-- very detrimental to the 190A since its main
-- advantage is speed and it often holds only a slight
-- edge.
-
- I just want to point out that elimination of the
- external drag inducing parts of the radiator may
- only cause a slight improvement in drag. It is the
- flow of the cooling air through the radiator system
- that causes most of the drag. Just because the air
- flows internally doesn't mean that it stops
- producing drag.
-
-
-
-
-
- Message Edited on 11/04/03 04:36PM by Oryx



Oleg Maddox
1C:Maddox Games

ZG77_Nagual
11-04-2003, 03:54 PM
Nice thread - very informative. This is what I understood of how the mustang radiator works, though I'd not have been able to put it so clearly.

http://pws.chartermi.net/~cmorey/pics/whiner.jpg

XyZspineZyX
11-04-2003, 03:56 PM
Oryx wrote:
- kyrule2 wrote:
-- The 190A used a system of internal mechanisms and
-- controllable gills as part of its cooling system and
-- had no external, drag inducing features. This would
-- really be a significant and, more importantly,
-- proper change to the 190 IMHO. The 190A suffers
-- heavily from radiator drag as it is now and this is
-- very detrimental to the 190A since its main
-- advantage is speed and it often holds only a slight
-- edge.
-
- I just want to point out that elimination of the
- external drag inducing parts of the radiator may
- only cause a slight improvement in drag. It is the
- flow of the cooling air through the radiator system
- that causes most of the drag. Just because the air
- flows internally doesn't mean that it stops
- producing drag.


What kyrule is trying to say is that Fw-190 gets the cooling from the cooling fan, there is no radiator flap setting that can be changed from the cockpit. For any other ww2 fighter when the pilot gets the overheat message, he should reduce MP/RPM and open the radiator. This is the main difference, Fw-190A pilot does not need to open any radiator flap. This is the moment when Fw-190A is in advantage, cooling is made simply by moving the trottle to max continuous setting, where in any other fighter the pilot should also open the radiators.

There is another advantage of the cooling fan. Cooling is made in function of engine speed (because it is geared to it) and not by the air speed. When a normal radial engine fighter climbs, he can use the max setting for only 1 minute, whereas Fw-190 has no aditional limitation. Also in dive radials often had problems with overcooling, which is a similarly dangerous condition for the engine (not simulated in FB). Fw-190A once again does not have problems with overcooling because the cooling is not a function of air speed, but engine RPM.

This is why all important post war radial engine fighters copied the Fw-190A cooling fan.


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Message Edited on 11/04/0309:56AM by Huckebein_FW

XyZspineZyX
11-04-2003, 04:03 PM
Oleg, if you still read this thread, please review CEM on german planes when Autopitch is selected. If I want to select max cruise setting, by moving the throttle to 1.0 ata, the RPM drops to idle (around 1300RPM), when it should stay above 2100RPM.

Also Fw-190 (at least A5 and later and D9) had constant speed props, not variable pitch props. Prop should behave like a constant speed prop the moment I switch to Manual Pitch, unfortunately it doesn't. Dora doesn't even have a pitch angle gauge.

Please take a look at german planes CEM.


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XyZspineZyX
11-04-2003, 04:06 PM
nevertheless in the Fw190 BMW cockpits was a crank that "made" something with the cooling !

http://www.jagdgeschwader53.flugzeugwerk.net/diverses/franky.gif

XyZspineZyX
11-04-2003, 04:08 PM
Huckebein_FW wrote:

-
-
- This is why all important post war radial engine
- fighters copied the Fw-190A cooling fan.
-
-

What engines are those Huck?




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"Only a dead 'chamber pot' is a good 'chamber pot'!"

XyZspineZyX
11-04-2003, 04:12 PM
Huckebein_FW wrote:
- What kyrule is trying to say is that Fw-190 gets the
- cooling from the cooling fan, there is no radiator
- flap setting that can be changed from the cockpit.

As I understood it, he specifically asked about cooling drag. The fan doesn't make a difference there - the air still has to move through the internal system and as such produces drag. In addition, the fan is taking energy from the engine, which overall has a very similar effect to drag.

The other points you are raising (about the operation of the system) may be worth having a look at, but I was responding to what the original poster wrote about drag.

XyZspineZyX
11-04-2003, 04:19 PM
Both Bf-109 and FW-190 had constant speed propeller automatic. We may name it by different ways in different languages, but even sovit planes had this automatics with constant speed prop....

It drops initially due to low speed of changind the prop pitch by automatics.

Howver I told already that engine gauges do not reflect 100% correct settings on low rpm. That was currently no possible to model.


D-9 had not this gauge historically.


Huckebein_FW wrote:
- Oleg, if you still read this thread, please review
- CEM on german planes when Autopitch is selected. If
- I want to select max cruise setting, by moving the
- throttle to 1.0 ata, the RPM drops to idle (around
- 1300RPM), when it should stay above 2100RPM.
-
- Also Fw-190 (at least A5 and later and D9) had
- constant speed props, not variable pitch props. Prop
- should behave like a constant speed prop the moment
- I switch to Manual Pitch, unfortunately it doesn't.
- Dora doesn't even have a pitch angle gauge.
-
- Please take a look at german planes CEM.
-
-
- <center> <img
- src="http://www.stormbirds.com/images/discussion-m
- ain.jpg"> </center>



Oleg Maddox
1C:Maddox Games

XyZspineZyX
11-04-2003, 04:22 PM
Huckebein_FW wrote:
- Oleg, if you still read this thread, please review
- CEM on german planes when Autopitch is selected. If
- I want to select max cruise setting, by moving the
- throttle to 1.0 ata, the RPM drops to idle (around
- 1300RPM), when it should stay above 2100RPM.
-
- Also Fw-190 (at least A5 and later and D9) had
- constant speed props, not variable pitch props. Prop
- should behave like a constant speed prop the moment
- I switch to Manual Pitch, unfortunately it doesn't.
- Dora doesn't even have a pitch angle gauge.
-
- Please take a look at german planes CEM.
-


sry, but , all Fw190 BMW and Junkers have a CSP in 1.11 and 1.2b .

the Doras RPM is just very high, but that was a feature of the Jumo213 ! because he gots his power from his RPMs not from the cubic capacity.


that the Dora has no "pitch gauge" is historical, it had none

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XyZspineZyX
11-04-2003, 04:31 PM
MiloMorai wrote:
-
- Huckebein_FW wrote:
-
--
--
-- This is why all important post war radial engine
-- fighters copied the Fw-190A cooling fan.
--
--
-
- What engines are those Huck?


Tempest V and Fury had such cooling fans.


<center> http://www.stormbirds.com/images/discussion-main.jpg </center>

XyZspineZyX
11-04-2003, 04:36 PM
Thanks for the response Oleg, and you are correct that "eliminate" was too strong of a word. I hope you will still check/consider reducing it as you say.

Huckebein did get the gist of my thread. This is a very informative thread, thanks for all the responses.

Oh, and it is good to see you Oleg, hope all is well.

<center>
http://www.brooksart.com/Icewarriors.jpg

"Ice Warriors", by Nicolas Trudgian.

Message Edited on 11/04/03 03:37PM by kyrule2

Message Edited on 11/04/0303:40PM by kyrule2

XyZspineZyX
11-04-2003, 04:59 PM
Those are a/c, not engines Huck./i/smilies/16x16_smiley-happy.gif

Tempest V was powered by the H-block Napier Sabre, a liquid cooled engine, and never had a 'cooling fan'.

Since when was just only the Bristol Centaurus an important post war radial engine for fighters.



Huckebein_FW wrote:
-
-
- Tempest V and Fury had such cooling fans.
-
-


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"Only a dead 'chamber pot' is a good 'chamber pot'!"

XyZspineZyX
11-04-2003, 05:06 PM
MiloMorai wrote:
- Those are a/c, not engines Huck./i/smilies/16x16_smiley-happy.gif
-
- Tempest V was powered by the H-block Napier Sabre, a
- liquid cooled engine, and never had a 'cooling fan'.
-
- Since when was just only the Bristol Centaurus an
- important post war radial engine for fighters.

I meant Tempest II.
Bristol Centaurus was the only important post war radial engine used for the first time for fighters that entered in production after ww2. (I know that some Tempest II were produced before VJ day, but none were used in combat before VJ day).


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Message Edited on 11/04/0311:10AM by Huckebein_FW

XyZspineZyX
11-04-2003, 05:27 PM
Huckebein_FW wrote:

-
- I meant Tempest II.
- Bristol Centaurus was the only important post war
- radial engine used for the first time for fighters
- that entered in production after ww2. (I know that
- some Tempest II were produced before VJ day, but
- none were used in combat before VJ day).
-
-

How can it be a post war fighter engine if there was a/c produced during WW2? In fact, it had been used since June 1943 to power the Tempest.

The F4U-5 and later marks did not use a fan. These were produced from 1946. With almost 800 a/c built, this is more than the SF.


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"Only a dead 'chamber pot' is a good 'chamber pot'!"

XyZspineZyX
11-04-2003, 05:41 PM
MiloMorai wrote:
-
- Huckebein_FW wrote:
-
--
-- I meant Tempest II.
-- Bristol Centaurus was the only important post war
-- radial engine used for the first time for fighters
-- that entered in production after ww2. (I know that
-- some Tempest II were produced before VJ day, but
-- none were used in combat before VJ day).
--
--
-
- How can it be a post war fighter engine if there was
- a/c produced during WW2? In fact, it had been used
- since June 1943 to power the Tempest.

Tempest II by everybody is considered a postwar Tempest variant. Since Tempest II was the first production fighter to receive Bristol Centaurus engines, then it was a postwar engine.


- The F4U-5 and later marks did not use a fan. These
- were produced from 1946. With almost 800 a/c built,
- this is more than the SF.

Yes, but all Corsairs had troubles with overheating in climb. Also -32W on Corsair had little modifications over it's ww2 predecesor -18W, only ancillary systems were different: superchargers, boost control and so on.

Anyway this is completely beside the point. If you want to discuss this further open another thread.



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Message Edited on 11/04/0311:42AM by Huckebein_FW

XyZspineZyX
11-04-2003, 06:00 PM
Huckebein_FW wrote:

- Anyway this is completely beside the point. If you
- want to discuss this further open another thread.


Indeed, please take that topic somewhere else.


<center><img src= "http://perso.wanadoo.fr/christophe.arribat/stoffwjabo.jpg" height=205 width=385>

<center>"We are now in a position of inferiority...There is no doubt in my mind, nor in the minds of my fighter pilots, that the FW190 is the best all-round fighter in the world today."

British Air Marshall, Sholto Douglas, 17 July 1942

XyZspineZyX
11-04-2003, 06:10 PM
JG53Frankyboy wrote:
- i wonder if a Pilot of a Fw190 with BMW engine could
- set the Side "flaps" of his cooling system to
- automatik with his crank ?

Right, it shouldn't have automatic cooling flaps. Please correct that.
And as you're there, pls consider changing the how to control radiators. It would be easier with 3 keys (I just give some key bindings which could be default then):
E - "Open" radiator/cowling flaps one notch
C - "Close" radiator/cowling flaps one notch
E + C (yep, that's a new button then when pressing both) - Switch between Auto and Manual
Like this, It's easier to get to certain positions instead of rolling though all options (Closed, 2, 4, 6, 8, Opened and Auto) in one direction. It was suggested already some times here. Many players would appreciate it /i/smilies/16x16_smiley-happy.gif .

Oleg_Maddox wrote:
- Both Bf-109 and FW-190 had constant speed propeller
- automatic. We may name it by different ways in
- different languages, but even sovit planes had this
- automatics with constant speed prop....

There's still a difference. CSP regulate the rpm with a governor, which is like a restriction ("don't get higher than xxx"). And the Variable Prop + Automatic (like in 109s and 190As) just had all the range and could overrev very much at high speeds, and the automation worked different than the CSP's one.
BTW what's an aerochemical prop??? I saw that description in the FB readme, but I only see CSPs, fixed props and variable pitch + auto props in game...
CSP also should be able to overrev when reaching high speeds in a dive with "100% prop pitch" (in FB terms), and in fast accerelation. B-239 can overrev at 650km/h Indicated BTW, the only one that can in FB. I tried La-7, and it overreved at ~4000 rpm which is a lot more than 2500 which is maximum. I reached it by diving 600km/h IAS, then shutting down and restarting the engine in that dive. It runs up very much then. Well, Hurricanes and P-39 can even withstand 5000 or more rpm. Please have a look at this /i/smilies/16x16_smiley-happy.gif .

-
- It drops initially due to low speed of changind the
- prop pitch by automatics.
-
-
- Howver I told already that engine gauges do not
- reflect 100% correct settings on low rpm. That was
- currently no possible to model.
-
-
- D-9 had not this gauge historically.
-
-
- Huckebein_FW wrote:
-- Also Fw-190 (at least A5 and later and D9) had
-- constant speed props, not variable pitch props. Prop
-- should behave like a constant speed prop the moment
-- I switch to Manual Pitch, unfortunately it doesn't.
-- Dora doesn't even have a pitch angle gauge.

I never read about a FW-190A habvin a constant speed prop.
As far as I know they all had VDM Verstelluftschraube. I also have an american D-9 report. Think it's NACA. There it says it has a VS-111 constant speed prop or something like that. That would fit, too. Dora hasn't that prop pitch gauge because it has a CSP while the A models have that gauge, because they have a VDM like the 109s.
BTW: In Stuka I read "Achtung! Vollautomatische Verstelluftschraube - nach Ladedruck fliegen" in cockpit.

http://home.t-online.de/home/luftarchiv/cockpits/ju87.htm

(fully automatic variable pitch propeller - fly by manifold pressure)
And that's what the pilots also do in 109s. Fly by manifold pressure. Also when the FW Dora was new, Kurt Tank reported something like "nach Drehzahl fliegen" (fly by RPM), opposing to the A models where you fly by manifold pressure. That really describes the difference in systems.
The Junkers doesn't have that gauge BTW. Could be that it doesn't have a manual mode, it's quite slow and if the automatic get's broken, there's not that big difference of power like in fast planes.

XyZspineZyX
11-04-2003, 06:11 PM
Hi Oleg and thanks for your answer. I know it's very hard to answer to questions here on the forum, since every discussion eventually ends in a flame fest. But I'm very happy that sometimes you find the time to come here.



Oleg_Maddox wrote:
- Both Bf-109 and FW-190 had constant speed propeller
- automatic. We may name it by different ways in
- different languages, but even sovit planes had this
- automatics with constant speed prop....

Oleg I was not talking about the Auto Pitch setting on german planes, only about the Manual Pitch setting. Now the propeller on Fw-190 variants do not act like a constant speed prop when Manual Pitch is selected, though they should.

For example if I select max setting on Dora (1.8ata/3250RPM) with Automatic Pitch, then switch to manual, I can't select Prop Pitch: 100% like in any other constant speed ropeller plane. In fact I can't select anything above Prop Pitch: 60% without overreving the engine. This is not the behaviour of a constant speed propeller, rather of a variable pitch prop. If it was a constant speed prop on Dora moving the prop pitch to 100% should keep the RPM at 3250, now it will pass over 3500RPM.

The same is valid for the BMW801 equipped Fw-190.



- It drops initially due to low speed of changind the
- prop pitch by automatics.

It's true that when you change RPM and pitch for a lower setting then push throttle and RPM full forward it should take some time until the prop pitch is changed. But for some unknown reason german propellers take the longest time to move in pitch, whereas in reality allied pilots feared to drop the RPM setting below max because they felt that pitch change speed kept them in disadvantage in regard with german planes.



- Howver I told already that engine gauges do not
- reflect 100% correct settings on low rpm. That was
- currently no possible to model.


I understant that 100% accuracy is not possible. However the basic Emergency, Climb, Max Cont. and Max Cruise maybe won't be that hard to simulate. The manifold pressure should give the setting and the RPM should automatically change to preselected position (only in conjunction with Autopitch of course).

For example in a G2:
Emergency setting at 1.42ata, RPM should move to 2800 - correct in FB.

Climb and Combat setting at 1.3ata should move the RPM needle to 2600RPM - correct in FB.

Max Continuous at 1.15ata has a correspondent RPM at 2300RPM - it cannot be selected with Autopitch though it should.

Max Cruise at 1.0ata with a correspondent 2100RPM cannot be selected with Autopitch. If I select 1.0ata the engine goes almost on idle.


- D-9 had not this gauge historically.

Yes I know, this was my point too. It hasn't because nobody used it from a long time ago, since Fw-190 (at least A5 and later) had constant speed prop with manual selection of pitch - in fact the pilot selected RPM not pitch.

So the whole point is that Fw-190A and D should have a constant speed propeller when Manual Pitch is selected, pilot adjusting directly the engine RPM not propeller pitch.



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Message Edited on 11/04/0312:26PM by Huckebein_FW

XyZspineZyX
11-04-2003, 06:19 PM
Huckebein_FW wrote:
-
-
- Anyway this is completely beside the point. If you
- want to discuss this further open another thread.
-
-

Then you should not have mentioned what you did without including the engine(s) that did use a fan./i/smilies/16x16_smiley-happy.gif



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"Only a dead 'chamber pot' is a good 'chamber pot'!"

XyZspineZyX
11-04-2003, 06:28 PM
and my "feeling" is that ALL Fw190 (BMW and Jumo) have a CSP in the game ! /i/smilies/16x16_smiley-wink.gif

i try it that way:

fly straight with 110% , auto prop.

than go to manual, the RPM will increase BUT will stop at a "border". the border will be still holde when you are in a dive. thats for me a CSP like they work in the Game.
you cant overriew in the dive /i/smilies/16x16_smiley-wink.gif


if you change to manual while in a 109 with 110% power, your RPM will increase endless till your engine will die (very quick)

btw, all that tests are at 100% Pitch while on manual /i/smilies/16x16_smiley-wink.gif


and if you lower the pith at 110% power, it will take a while till the RPMs decrease - exactly that way handle all other CSPs from Yaks Las P-40 and so on.

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XyZspineZyX
11-04-2003, 06:35 PM
and btw, if you go to manual in the BMW 190s, you can see the pitch "watch" still moving - at a given RPM setting . so the governour of the Propeller is still trying to keep the RPMs stable with changing the angle of the propeller blades

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XyZspineZyX
11-04-2003, 06:41 PM
JG53Frankyboy wrote:
- and my "feeling" is that ALL Fw190 (BMW and Jumo)
- have a CSP in the game ! /i/smilies/16x16_smiley-wink.gif
-
- i try it that way:
-
- fly straight with 110% , auto prop.
-
- than go to manual, the RPM will increase BUT will
- stop at a "border". the border will be still holde
- when you are in a dive. thats for me a CSP like they
- work in the Game.
- you cant overriew in the dive


Yes it stops slightly above 3500RPM with Prop Pitch 100% for Dora and it doesn't kill the engine but it will overheat much faster since it overrevs the engine (and there are no performance gains). Also if you move the throttle to 100% the RPM will drop below 3000RPM. In all other CSP planes if you move the throttle from 110 to 100% the RPM doesn't move at all. For Dora it moves more than 500RPM. So it overrevs and it can't keep the RPM selected for slight changes in manifold pressure, so it is not a CSP. But it should be.



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Message Edited on 11/04/0312:44PM by Huckebein_FW

XyZspineZyX
11-04-2003, 06:47 PM
Willey wrote:
--
-- Huckebein_FW wrote:
--- Also Fw-190 (at least A5 and later and D9) had
--- constant speed props, not variable pitch props. Prop
--- should behave like a constant speed prop the moment
--- I switch to Manual Pitch, unfortunately it doesn't.
--- Dora doesn't even have a pitch angle gauge.
-
- I never read about a FW-190A habvin a constant speed
- prop.


It's in the NACA description of A5 Kommandogerat. I guess they knew how to make the difference between a constant speed prop and a variable pitch one. /i/smilies/16x16_smiley-wink.gif



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XyZspineZyX
11-05-2003, 01:00 AM
Oleg_Maddox wrote:

- Sorry, but Skychimp is wrong in that opinion.
- The drag is present anyway for the closed radiator.
- But in this position the construction of radiator
- cowling with laminar flow around it really has small
- drag that allow to get greater speed of the plane
- itself in comparison with usual radiator cowl placed
- in that aerodynamically 100% _optimal_ area (like
- say on Yak-3 or on Yak-9U, that has it in the same
- place, but hasn't laminar airflow in the place of
- the P-51D airintake and fuselage. Germans also tried
- to place there after great experimantal works, but
- it was too late...You may see it on experimental FWs
- and Bfs). But when it begins to open - drag will
- increases anyway.

Oleg, I am not wrong.

Yes, the P-51 radiator duct created drag when it was closed, and yes it was small in comparison to contemporary airplanes.

But the drag was even lower when the radiator air exit shutter was opened enough to create a backpressure which could be convertred into thrust, largely counteracting the drag.

You are of the opinion that the P-51 was at its "most aerodynamic" when the radiator exit door was closed. But the designer of the system, Lee Atwood, says that optimal efficiency came when it only closed enough to develope the backpreassure necessary to create thrust.

"Only closed enough" is the same as saying partially open.



Regards,

SkyChimp

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XyZspineZyX
11-05-2003, 11:47 AM
All the radials seem to have alot of drag and shouldnt 190 LA P47 in 1.11

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