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XyZspineZyX
08-20-2003, 11:25 AM
Now, I've thought about this before /i/smilies/16x16_smiley-wink.gif

Should cowl flaps really always slow you down ?

I mean, here's how I look at it: air enters certain space (radiator or air cooled engine). If the air can't get out in the same direction as it entered, you have drag. This happens when cowl flaps are closed. Of course, you don't have increased fuselage drag due to closed cowl flaps.

Now, if you open cowl flaps, you let the air have exit route and you actually lower the drag. But now youhave higher fuselage drag due to open cowl flaps. Also, you have some kind of jet stream effect, with hot air generating a little thrust (wasn't P51 credited with this advantage ?).

Maybe cowl/radiator flaps were useful in regulating engine temperature, but were they that influential on drag ? I don't know, please enlighten me...

I've never seen cowl/radiator flaps on Fw 190A, unlike P47, P51, Fw190D-9, Bf/Me 109, F4U, F6F, LaGG, Yak or Spitfire. I've never seen them on A6M as well.

<center>http://easyweb.globalnet.hr/easyweb/users/ntomlino/uploads/sig.jpg

Message Edited on 08/20/0311:26AM by Hristos

XyZspineZyX
08-20-2003, 11:25 AM
Now, I've thought about this before /i/smilies/16x16_smiley-wink.gif

Should cowl flaps really always slow you down ?

I mean, here's how I look at it: air enters certain space (radiator or air cooled engine). If the air can't get out in the same direction as it entered, you have drag. This happens when cowl flaps are closed. Of course, you don't have increased fuselage drag due to closed cowl flaps.

Now, if you open cowl flaps, you let the air have exit route and you actually lower the drag. But now youhave higher fuselage drag due to open cowl flaps. Also, you have some kind of jet stream effect, with hot air generating a little thrust (wasn't P51 credited with this advantage ?).

Maybe cowl/radiator flaps were useful in regulating engine temperature, but were they that influential on drag ? I don't know, please enlighten me...

I've never seen cowl/radiator flaps on Fw 190A, unlike P47, P51, Fw190D-9, Bf/Me 109, F4U, F6F, LaGG, Yak or Spitfire. I've never seen them on A6M as well.

<center>http://easyweb.globalnet.hr/easyweb/users/ntomlino/uploads/sig.jpg

Message Edited on 08/20/0311:26AM by Hristos

XyZspineZyX
08-20-2003, 12:41 PM
actually have u ever looked at the radaitor in a car? there going to restric the air flow anyway so when u open the cowl/radiator flaps u just add the drag. thats how i looked at it anyway?but did they really make as big a differance in speed as they do in IL2?

XyZspineZyX
08-20-2003, 01:27 PM
yup, I think I know what you are saying. However, my logic is a bit different.

Let's say there is a surface behind radiator. The air which passes through it hits that surface. This, effectively, means maximum drag, both from radiator and the surface.

If you open that surface, some (more or less, of course) air manages to get through without hitting radiator and the surface. This suggests less drag, as certain amount of air simply passes through. However, I agree that this effect might be negated due to drag of open flaps on the fuselage.

Next, the "jet stream" effect was credited for some 200 lbs of thrust pn P51, wasn't it ?

Now again, I've never seen anything like cowl flaps on Fw 190A series. Yes, I know where air intake and fan are, where exhaust pipes are and that's about it. No other opening for the engine.

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XyZspineZyX
08-20-2003, 03:26 PM
That's an important question! I also many times asked myself why a 190A should slow down with the radiator opened, as no flaps are visible for that!

Cheers,

XyZspineZyX
08-20-2003, 04:18 PM
The A-series Fw190 did not have cowl flaps.

It used fan assisted cooling on the front of the engine. The 12-14 bladed fan was geared to spin faster (1.3X faster I believe?) than the prop itself.

This cooling air was sent through a series of ducts or "baffles" inside the engine that cooled the cylinders, etc.

Exhaust gasses were sent out through the slits or cooling "gills" behind the BMW801. These were modified to provide better cooling in the later variants.

British engineers after the war reffered to this cooling approach as "...thorough and ingenious".


<center><img src= "http://www.luftwaffepics.com/LCBW4/FW190-A0-52.jpg" height=215 width=365>

<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."

Sholto Douglas, 17 July 1942

XyZspineZyX
08-20-2003, 04:44 PM
IIRC the fan was geared to crankshaft, because the engine needed more cooling with RPM increase, but it was much more easily to gear it to propeller. Interesting to hear how it was in reality.


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

XyZspineZyX
08-20-2003, 05:04 PM
So in that case Opening & closing a radiator in fb for FW is not Historicaly correct ?

this should be unmodled & the speed corected for loss in current situation


The p39 doesent have any cowl flaps either theres a airscoop
behind the pilot where the air is ramed in maybe p39 needs this radiator Unmodled as well ?

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<center><FONT COLOR="white">The "Ace Edge"(c).
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XyZspineZyX
08-20-2003, 05:17 PM
.K.Davis wrote:
-
- FW190fan wrote:
-- @ Hristos:
--
-- A-series Focke-Wulfs do not have cowl flaps. It uses
-- fan assisted and ducted cooling within the cowl and
-- engine itself.
--
-- Heat exhaust's thru the exhaust slits or
-- "gills" on either side of the engine, behind the
-- cowling.
-
- So why do radiator settings have a drag effect in
- the 190A series?
-

Can someone come up with some documentation so we can get Oleg to unmodel this radiator/cowlflaps/drag situation

I mean if we can prove that this cooling system was basicaly runing all the time, then the top speed @ sealevel
would have to be adjusted with a constanty operational type of radiator for FW we shouldnt have cowl-drag modled for FW cooling system.



<center><FONT COLOR="white">ӚFJ-M œ R D ˜ ӡ[/i]</font>

<center> http://www.onpoi.net/ah/pics/users/ah_109_1059752328.jpg </center>

<center><FONT COLOR="white">The "Ace Edge"(c).
With my incremental trim
I am actually able to turn so quickly that, I never turn at all.
In Fact the Planet Earth rotates around the Axis of My PC, thus giving me the optimum turn rate and insuring that you
the bandit are promptly fraged !!!
In memory Of Ray R.I.P.[/i]</font>

XyZspineZyX
08-20-2003, 05:18 PM
Actually, I looked it up and according to the British, the cooling fan of their A-3 ran at 3.143 times the "airscrew" speed.

Interesting that the fan on the larger and more powerful BMW 802 ran at 1.85 times the "crankshaft" speed.




<center><img src= "http://www.luftwaffepics.com/LCBW4/FW190-A0-52.jpg" height=215 width=365>

<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."

Sholto Douglas, 17 July 1942

XyZspineZyX
08-20-2003, 05:33 PM
FW190fan wrote:
- Actually, I looked it up and according to the
- British, the cooling fan of their A-3 ran at 3.143
- times the "airscrew" speed.
-
- Interesting that the fan on the larger and more
- powerful BMW 802 ran at 1.85 times the "crankshaft"
- speed.


Yep strange, I remember a source saying that it was geared with a 3.1... ratio with crankshaft. I'll search later for data.


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XyZspineZyX
08-20-2003, 06:05 PM
Hristos,

I have seen on the history channel and read some 30 years ago about the advantages of the cooling system on the p51.
As you know the success of the p51 has been attributed to the laminar flow wing. The manufacture and the US Gov. specificaly released this information to missinform everyone.
Some of the advantage in speed was gained by the thrust produced by the cooling (aprox. 15mph advantage) system. They were afraid that if they released this information that germany would apply the same principles and take advantage of the same speed gain, and lose the advantage.
Therefore all the talk about how high speed was attained by the p51 was attributed to the laminar flow wing. Many books still attribute the high speed of the p51 to the laminar flow wing only.
Germany admited after the war that they were aware of the thrust produced by the cooling system of the p51, and documents were found that they also found simular results in some of there own tests.
I would assume that the high speed attained by the p51 was due to not one inovation but the combination of laminar flow wings , cooling thrust, low coeficient, ect. The p51 did attain a high speed with a relitively low horse power engine, as many other planes had much more horsepower and less attainable speed. One of the goals with the p51 was to maintain low fuel consumption while extracting maximum speed. This is only possible with lower horspower engines and aerodynamic refinement.
Since the thrust produced by the cooling system of the p51 was not as much of a secret as the US and UK thought it was. One could only assume that other countries due to there own testing had found similar results. Therefore it would be very possible that some of the same properties (thrust or lack of drag) was attained in other aircraft.
Since many manufactures and Governments do there best to maintain secrets. It is obvious that some of these details are hard to come by. Many of the p51 pilots were not aware of the thrust producing cooling system for fear of capture and leaking of the secret during interogation. Personal are allways misinformend by governments to keep secrets as long as possible. I am sure that some pilots and mechanics had to be aware of the thrust affect but on a need to know basis only.
My uncle was a p51 crew chief in the Korean war. He is very ill right now but I will ask him about the thrust next time I talk to him he might remember some details.
IMO I also feel that the drag affect on the fw190 may not be warrented. Also if you look at yaks from the outside it appears to have a similiar cooling system compared to the p51. Yaks are a relitively low horspower and high speed aircraft.
I am not an aerodynamic engineer nor intricatly familiar with the aerodynamics of each aircraft's cooling system. But perhaps someone with such credintials could take a deeper look into the details as history has shown some things are not as first advertised.

ReapALL ---> usualy go by Vulgar but I have not posted in so long I cannot remember my password.

XyZspineZyX
08-20-2003, 06:13 PM
@ Cowl flaps and FW190A, from "Janes Fighting Aircraft of WWII":

"The introduction of positive air cooling, incorporating a cooling fan in the cowl nose opening, operating at approximately three times the airscrew speed, and a system of internal baffles had made it possible to eliminate all external cowling excrescences."

===============================

If no external cowlings, no drag inducing radiator function, why would radiators slow the FW190 down?


<center><img src= "http://www.luftwaffepics.com/LCBW4/FW190-A0-52.jpg" height=215 width=365>

<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."

Sholto Douglas, 17 July 1942

XyZspineZyX
08-20-2003, 06:13 PM
Interesting Post Reap

<center><FONT COLOR="white">ӚFJ-M œ R D ˜ ӡ[/i]</font>

<center> http://www.onpoi.net/ah/pics/users/ah_109_1059752328.jpg </center>

<center><FONT COLOR="white">The "Ace Edge"(c).
With my incremental trim
I am actually able to turn so quickly that, I never turn at all.
In Fact the Planet Earth rotates around the Axis of My PC, thus giving me the optimum turn rate and insuring that you
the bandit are promptly fraged !!!
In memory Of Ray R.I.P.[/i]</font>

XyZspineZyX
08-20-2003, 06:19 PM
Huckebein_FW wrote:

- Yep strange, I remember a source saying that it was
- geared with a 3.1... ratio with crankshaft. I'll
- search later for data.


According to Janes the fan was:

"...driven from the airscrew reduction gear at 1.72 times crankshaft and 3.17 times airscrew speed."

So ===>crankshaft===> airscrew reduction gear ===> fan gear.


<center><img src= "http://www.luftwaffepics.com/LCBW4/FW190-A0-52.jpg" height=215 width=365>

<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."

Sholto Douglas, 17 July 1942

XyZspineZyX
08-20-2003, 07:34 PM
Ment to post this hear so now I will http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

Some snipits copied from that sight I posted speaking about cooling the FW in the early years & final developments


Technical Department of RLM (Technisches Amt) developed specifications for the new fighter plane in the winter of 1937/38 During the spring of 1938 these specifications were sent to manufacturers including Focke-Wulf Flugzeugbau AG.
As a result of work under the supervision of Prof. Kurt Tank and engineer Rudolf Blaser, a relatively small fighter
of compact construction powered by radial AIR-cooled engine was developed.


This was a new BMW company design created by the joining of two BMW 132 nine-cylinder radial engines.
This engine limited pilot's visibility from cockpit even more but rated at 1550 hp (1140 kW) it was about 1/4 more efficient than in-line engines such as the DB-601 or Jumo 211, and able to absorb more battle damage. This high engine power came with troubles with the cooling system that were resolved by introduction in the first prototype, Fw 190 V1, (W.Nr.0001) of a special propeller tunnel spinner covering the engine cooling air inlet in the cowling. The purpose of this cowling was to increase the cooling airflow over the engine and reduce the pressure drag.


The engine cowling was not as good as expected and the engine still had a tendency to overheat. This problem was so severe that even during low powered flight cockpit temperature rose to 55*C. In addition, the cockpit was not properly sealed and exhaust gases had leaked into it. The exhaust gas level was dangerous for the pilot and only his oxygen mask saved Hans Sander from asphyxiation during the first flight.

The Fw 190 had shown a surprisingly high maximum speed during horizontal flight without armament at the altitude of 4000 m - 595 km/hr. Next, the plane was returned to the manufacturer for necessary modifications, especially in the
cooling system. In the case of radial engines there was only one possible solution: to increase airflow over the engine. This was done by using a ten blade fan on the propeller shaft, in front of the engine, near the cowling.
The tunnel spinner was replaced by a traditional spinner, covering only the airscrew hub of the VDM metal propeller.
It was decided to use this after tunnel trials which had shown that the big spinner had not given proper airflow for
efficient engine cooling and its influence on the reduction of pressure drag was not significant. Engine cooling was
improved after this modification, but not to the expected level, and the engine still operated in the high range of
acceptable temperatures


Flights were made from Rechlin-Roggenthin airfield. Later this unit was transferred to Le Bourget near Paris.
During these intensive tests frequent engine failures occurred. The BMW 801 engine still had a tendency to
overheat, especially the back bank of cylinders. Overheating occurred generally on the ground during long runs at low power when the flow of cooling air was reduced to a minimum.

In the Technical Office, reports concerning the Fw 190A-1 main problems still were concentrated on engine overheating


The Fw 190A-2 was the second series variant and was powered by the modified BMW 801C-2 engine. In this model, problems
with the engine rear bank of cylinders overheating were finally solved by the simple introduction of a ventilation slot on the two sides of the engine cowling. The same slots were also introduced in the Fw 190A-1 in service.


During production, in some Fw 190s another modification was applied. In place of the ventilation slots, engine cowling
shutters controlled from the cockpit were installed. The pilot could precisely control the engine temperature by
regulation of the shutters.


<center><FONT COLOR="white">ӚFJ-M œ R D ˜ ӡ[/i]</font>

<center> http://www.onpoi.net/ah/pics/users/ah_109_1059752328.jpg </center>

<center><FONT COLOR="white">The "Ace Edge"(c).
With my incremental trim
I am actually able to turn so quickly that, I never turn at all.
In Fact the Planet Earth rotates around the Axis of My PC, thus giving me the optimum turn rate and insuring that you
the bandit are promptly fraged !!!
In memory Of Ray R.I.P.[/i]</font>

XyZspineZyX
08-20-2003, 08:35 PM
I am going to try to find the program the History channel had on the develptment and manufacturing of the p51, since they can be purchased. I know they have a number of different films on the p51, so finding the right one will probably be the problem.
This particular film was more specific to the developtment and manufaturing details. The open admission of missleading everyone about the cooling thrust was the most interesting. As engineers and test pilots openly discussed it and stated the reasons for intentionaly missleading everyone.
They also discussed some of the German planes in comparison to the p51 cooling system and the german knowledge of the thrust effects.
Wish I could remember more details from the articles I read 20-30 years ago. I think it was an article in one of the warbird magezines that went into specifics and had drawings comparing the effects of various types of cooling systems in ww2 aircraft.
Unfortunatly when I joined the army I left some boxes full of magazines and books at home, all pertaining to aircraft. When I returned on leave for the first time, I found that my mother had thrown them all away. I asked her why, she stated that it was just a bunch of junk and what would I want with all that now that I was grown up. I followed with some choice vocabalary, words of such I had never used towards my mother. She did not like what I had to say. : )
I am displeased that the books and magazines are now lost, as it is dificult and or impossible to replace some. I had A few items were given to me by pilots who participated in ww2, we lived in a retirement community and there were a lot of ww2 vets. I have heard many personal accounts, just wish I could remember all the details.
I am sure that there must be documentation going into the specifics of the cooling systems and there affect on drag. Though finding them may be difficult for all the types of aircraft. Plus sifting through and finding the true details can be difficult as many things have been written for profit not authenticity.
Would be nice to see this thread stick to discussing and enlightning the subject rather than deteriate into what the majority of threads end up as.
This is a very important subject as those of us that are concernend about attention to the real details. Would like to see this simulation to be as accurate as possible. I personaly am not interested in having an uber plane or care about being invincible. What I do like is having the planes modeled as accuratly as possible so that the strenths and weakness's can be utilized. Pilot skill and tactics should be the manner used to obtain victory, not gaming the game or code inconsistancy exploitation.
Unfortunatly some IL2 players have no real knowledge of aircraft and or aerodynamics or care one bit. They only want there favorite plane to be invincible like there player in some other fantasy based game. Perhaps some day some will learn that it's about experincing how it realy was and not about satisfation of a self indulged and over inflated ego. I am tired of hearing I want I want I want what I want so I can win and be invincible because I do not want to use skill knowledge and tactics because I just want to win, I WANT TO BE INVINCIBLE!!

ReapALL

XyZspineZyX
08-20-2003, 08:55 PM
Hummm Guys the 190 do had manualy actuated cool flaps, the handcrank on the dashboard being used to open/close them.

Butch

XyZspineZyX
08-20-2003, 09:18 PM
And I think Hristos's explanation may be incorrect (note I can not prove it). But by definition the 'cowl flaps' button (whether it opens a flap over a radiator, or as in case of FW190 flaps in the engine cowling) causes greater cooling, in order to get this greater cooling effect air must be ducted over a 'radiator' and/or the engine itself (as in an aircoold application). All aircraft are designed with least possible drag, and the least possible drag is achieved by NOT having air pass over bulky un-aerodynamic parts (like a radiator or an engine), the problem is that not enough cooling can be achieved in this manner, so an adjustable 'flap' is installed to give either 'least drag' or 'most cooling' effects (or somewhere in between), just as we have in FB. Now you could argue all day as to whether a specific aircraft has too much or little drag with the 'flap' set to maximum or minimum cooling, I wouldn't touch that with a ten foot pole.

As regards to the FW190 (A4 and upwards), its 'flap' is located inside of the engine cowling, and might be considered 'open' to get the least amount of drag (air from fan passes directly out through the exhaust ports, which are visible on the 'skins' in FB), but this will provide least amount of cooling. When these flaps are 'closed' the air is ducted over the oil coolers and engine before being 'expelled' out of the exhaust ports(?). Though operation this is the opposite of say a Bf109, or a P40, it is just semantics (open/closed), and the results are basically the same.

XyZspineZyX
08-20-2003, 09:29 PM
ZG77_Lignite wrote:
- As regards to the FW190 (A4 and upwards), its 'flap'
- is located inside of the engine cowling, and might
- be considered 'open' to get the least amount of drag
- (air from fan passes directly out through the
- exhaust ports, which are visible on the 'skins' in
- FB), but this will provide least amount of cooling.
- When these flaps are 'closed' the air is ducted over
- the oil coolers and engine before being 'expelled'
- out of the exhaust ports(?). Though operation this
- is the opposite of say a Bf109, or a P40, it is just
- semantics (open/closed), and the results are
- basically the same.

Thank you Lignite, that's a clear explanation. Now we just need to figure out:

1. Why the default "closed/auto" setting produces different drag effects than the player-selected "closed/auto" position?

2. What the effects of cooling versus drag are with the aircraft left on the default setting?


--AKD

http://www.flyingpug.com/pugline2.jpg

XyZspineZyX
08-20-2003, 09:42 PM
Just my two cents about radiator flaps.
Several years ago I read in a book about Yak-1 that first Yak-1 variants had only manual radiator flaps. This was described as dangerous, especially for young inexperienced pilots in a heat of combat, because it could lead either to engine overheating (due to not enough cooling) or bigger drag (slower speed). The book stated that introduction of some kind of automatic radiator flap controller was a big step forward in making Yak-1 more friendly to (especially) inexperienced flyer.

My comment is, should open radiator flaps cause minimal drag, they'd had fixed them open, thereby preventing problems with engine overheating. But they designed special device for this purpose so I think drag was considerable.
I'd agree with the explanation posted above. Closed radiator flaps give airframe nice and aerodynamic, smooth shape. Open radiator flaps cause air to flow around parts of a engine or cooling system - this is certainly more drag.

Ach, almost forgot. I also read that first versions of famous Zero had problems with overheating cylinders (from second "star"). I read that mechanics from field unit fixed it by mounting "small parts of metal" which "directed" air flowing between cylinders of first "start" precisely at cylinders of second "star". I believe this field modification was adopted in serial production of later Zero models.

Michal

XyZspineZyX
08-20-2003, 10:03 PM
Theres 3 flaps on each side behind the exhaust openings.

XyZspineZyX
08-20-2003, 10:49 PM
butch2k wrote:
- Hummm Guys the 190 do had manualy actuated cool
- flaps, the handcrank on the dashboard being used to
- open/close them.
-
- Butch
-



Hi butch2k, I just copied my other reply from the A-5 thread in GD as I am interested in your thoughts:



-Yes, I am aware of the ventilation flap control
- lever located above the fuel gauge. It is my
- understanding that these controlled the egress of
- exhaust from the cooling louvers or "gills" located
- behind and on each side of the engine.
-
- However, this cooling arrangement is different from
- the typical external cowl flaps on aircraft such as
- the P-47, F4U or even the long-nose 190s with
- annular radiators such as the Dora. When these
- aircraft activate the cowl flaps they open outward
- and into the airstream.
-
- It is my understanding that the cooling louvers on
- the A-series Focke-Wulfs do not open outward
- (externally) into the airstream. This is from Janes
- "Fighting Aircraft of WWII":
-
- "...a system of internal baffles had made it
- possible to eliminate all external cowling
- excrecences."



<center><img src= "http://www.luftwaffepics.com/LCBW4/FW190-A0-52.jpg" height=215 width=365>

<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."

Sholto Douglas, 17 July 1942

XyZspineZyX
08-20-2003, 11:21 PM
Completely agreed A.K.Davis, there is definitely a problem with somewhere, certainly on the FW190A's, which is the only aircraft I am really familiar with, and apparently on all aircraft with the 'auto/closed' radiator setting. The performance advantage is unrealistic and noteable. It certainly seems that the 'default' (when aircraft first spawns) setting allows for maximum cooling (radiator 'open') with minimal drag (radiator closed), at the same time, instead of the correct operation of gradual drag increase as engine temp rises. With minimal testing, I wasn't able to reproduce the effect on the P-40.

XyZspineZyX
08-21-2003, 12:16 AM
ZG77_Lignite wrote:
- Completely agreed A.K.Davis, there is definitely a
- problem with somewhere, certainly on the FW190A's,
- which is the only aircraft I am really familiar
- with, and apparently on all aircraft with the
- 'auto/closed' radiator setting. The performance
- advantage is unrealistic and noteable. It
- certainly seems that the 'default' (when aircraft
- first spawns) setting allows for maximum cooling
- (radiator 'open') with minimal drag (radiator
- closed), at the same time, instead of the correct
- operation of gradual drag increase as engine temp
- rises. With minimal testing, I wasn't able to
- reproduce the effect on the P-40.

I just tested every single aircraft with auto radiator settings (i.e. all 109s, all 190s) and found the same results. There is a consistent 40-50kph speed loss between the default "auto/closed" setting and the "auto/closed" if selected by player. With every aircraft tested the default position appeared to offer the drag of the "closed" position and equal or maybe even superior cooling to the "open" position.

Also, the act of cycling through the settings does not appear to be causing these results, as aircraft with manual radiator suffer no speed loss when you quickly cycle from the default "closed" position back to the "closed" position.



--AKD

http://www.flyingpug.com/pugline2.jpg

XyZspineZyX
08-21-2003, 02:57 AM
ReapALL what you heard about "thrust" being produced by the exiting of warm air out the p-51 radiator is well b.s the thought that 200-300 degree air can produce thrust is not correct even in the least bit. alls is required to find out what the p-51 pilots did is to read their accounts and numerous ones report the closing of their radiator in order to gain speed especaly when trying to catch a enamy plane .. the reason closing cowel flaps or radiators reduce aero drag is that at that point less air is is allowed to flow through a high drag area i.e radiator or cylinder cooling fins.i hope things are a little clearer

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us infantry 84-91

XyZspineZyX
08-21-2003, 03:38 AM
Furthermore, the player-selected "closed/auto" position in the 109s and 190s is no different than the fully "open" position. Same drag, same cooling.

--AKD

http://www.flyingpug.com/pugline2.jpg

XyZspineZyX
08-21-2003, 03:46 AM
A.K.Davis, when you are finished testing could you please submit this to Oleg. Anyone else who has noticed a bug with the "auto" radiators, could you also please submit your findings. Thank You.

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

"Ice Warriors", by Nicolas Trudgian.

XyZspineZyX
08-21-2003, 04:40 AM
kyrule2 wrote:
- A.K.Davis, when you are finished testing could you
- please submit this to Oleg. Anyone else who has
- noticed a bug with the "auto" radiators, could you
- also please submit your findings. Thank You.


Already submitted, except the bit about player-selected "closed/auto" appearing to be exactly the same as "open" position, but that can be inferred, I think.



--AKD

http://www.flyingpug.com/pugline2.jpg

Message Edited on 08/21/03 03:40AM by A.K.Davis

Message Edited on 08/21/0303:40AM by A.K.Davis

XyZspineZyX
08-21-2003, 06:01 AM
I hope it is inferred A.K., that is a pretty significant part of the bug IMHO.

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

"Ice Warriors", by Nicolas Trudgian.

Message Edited on 08/21/0305:14AM by kyrule2

XyZspineZyX
08-21-2003, 06:35 AM
Hey, feel free to send it in. I would hope that fixing one would lead to fixing the other, since there should be no difference between the default "closed/auto" position and selecting that position yourself.

--AKD

http://www.flyingpug.com/pugline2.jpg

XyZspineZyX
08-21-2003, 06:49 AM
A.K., I didn't mean to sound ungrateful, just concerned. I meant to add a "thanks" to my last post but I forgot. Hope it gets fixed and thanks for submitting it.

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

"Ice Warriors", by Nicolas Trudgian.

XyZspineZyX
08-21-2003, 06:57 AM
Thanks for the input !

I did a quick test with Fw 190A-5, 100% fuel on the deck. After cycling several times through cowl flaps setting to make sure to clear the possible bug, it seemed that open cowl flaps take away some 35 kph of top speed on the deck.

It would be interesting to compare this speed loss to speed loss when carrying various ordnance. Didn't have time to do it yet though, sorry.

<center>http://easyweb.globalnet.hr/easyweb/users/ntomlino/uploads/sig.jpg

XyZspineZyX
08-21-2003, 06:02 PM
Hristos wrote:
- Thanks for the input !
-
- I did a quick test with Fw 190A-5, 100% fuel on the
- deck. After cycling several times through cowl flaps
- setting to make sure to clear the possible bug, it
- seemed that open cowl flaps take away some 35 kph of
- top speed on the deck.
-
- It would be interesting to compare this speed loss
- to speed loss when carrying various ordnance. Didn't
- have time to do it yet though, sorry.
-
- <center><img
- src="http://easyweb.globalnet.hr/easyweb/users/nto
- mlino/uploads/sig.jpg">


It should be noted that in both the 109 and 190, the radiator works just as expected under manual control (i.e. "closed" through "open" position). The problem is with the default and player-selected "closed/auto" position.


--AKD

http://www.flyingpug.com/pugline2.jpg

XyZspineZyX
08-21-2003, 07:24 PM
Ok I did some testing on my own super ultra accurate testing
Using the Gauges in the cockpit not the fullscreen gauges
you might be suprised @ the results then again maybe not

Ok a lil advance information, I used the qmb to create these tests 100% fuel @ 5000m after I achived a perfect 5000m using auto level combined with trim & reading the gauges in the Pit to maintain this perfect 5000m altitude the tests begin....

Here are the results
================================================== =========
Aircraft= FWA9
Prop Pth= Automatic
Throttle= 110%
Altitude= 5000m
Radiator= SpawnPosition(IE:Automatic/Closed)
Wep = On
Max Kmh = 510
OilTemp = 120c (peged on the gauge)

Flew like this for over 30min doesnot overheat
================================================== =========
Aircraft= FWA9
Prop Pth= Automatic
Throttle= 110%
Altitude= 5000m
Radiator= Automatic/Closed (Cycled to this Position)
Wep = On
Max Kmh = 460
OilTemp = 120c (peged on the gauge)

Flew like this for over 30min doesnot overheat
================================================== =========
Aircraft= FWA9
Prop Pth= Automatic
Throttle= 110%
Altitude= 5000m
Radiator= Cycled & selected FULL OPEN
Wep = On
Max Kmh = 460
OilTemp = 120c (peged on the gauge)
================================================== ==========
Aircraft= FWA9
Prop Pth= Automatic
Throttle= 110%
Altitude= 5000m
Radiator= Open
Wep = Off
Max Kmh = 430
OilTemp = 120c (peged on the gauge)

Flew like this for over 30min doesnot overheat
================================================== =========
Aircraft= FWA9
Prop Pth= Automatic
Throttle= 110%
Altitude= 5000m
Radiator= Closed
Wep = On
Max Kmh = 500 (*)see note below
OilTemp = 120c (peged on the gauge)

Flew like this for 25 seconds then the Overheat Warning came on, Imeadiataly cycled radiator to Open position it took 48 seconds before the Normal Signal came on this was repetable.

When I Opened the radiator (to the OPEN Position) to cool the engine all information corrilated with this faze of previouse testing...

Aircraft= FWA9
Prop Pth= Automatic
Throttle= 110%
Altitude= 5000m
Radiator= Automatic/Closed (Cycled to this Position)
Wep = On
Max Kmh = 460
OilTemp = 120c (peged on the gauge)

Engine Cooled in 48 seconds, Continued to fly like this for over 30 minuts engine did not re-Overheat

(*) before I could reach 510 the overheat warning came on altho in a later test 510 was achivable & was the max speed @ 5000m with rad closed & engine was overheating for aproximataly 45/50 seconds before I hit 510kmh.
================================================== ==========



In closing Id like to say there are one of two things hapining here....

Either there is a bug that is allowing FWA9 (among other AC)
to achive max kmh 510@5000m (emulating closed flap position but with Cooling Effects

OR

Once we Cycle to the Automatic/Closed Position we are Losing 50Kmh of top end speed for no reason, Wich is also a Bug.

If you will notice that during all tests the The Engine Oil Tempature Is Maxed out @ 120, I canot find the water temp gauge so Im guessing that the Overheat Warning is Trigered by Water temp not Oil Temp...

Either way the Automatic Radiator funtion is not working correctaly Im not sure tho what speed we should be achiving
@ 5000m 510 or 460 Kmh

Radiator spawn setting Automatic/closed 510kmh @ 5000m ?

Cycle to Radiator setting Automatic/closed 460kmh @ 5000m ?

sorry this is so long was trying to be very Precise
All Informative Input welcome

This is not a whine post but a post to define proper speed @ altitude & radiator settings




Message Edited on 08/21/0309:27PM by AFJ_Murdoc

XyZspineZyX
08-21-2003, 08:02 PM
- Either there is a bug that is allowing FWA9 (among
- other AC)
- to achive max kmh 510@5000m (emulating closed flap
- position but with Cooling Effects
-
- OR
-
- Once we Cycle to the Automatic/Closed Position we
- are Losing 50Kmh of top end speed for no reason,
- Wich is also a Bug.

Both, actually. Murdoc, there may be a separate issue with how long it takes the 190 to overheat (or the 190 engines may very well be that efficient). Try these same tests with a 109 and you'll get a better idea of what is going on with the automatic radiator settings. You should see no difference in results between the "open" position and the player-selected "closed/auto" position, given the same power settings.

--AKD

http://www.flyingpug.com/pugline2.jpg

XyZspineZyX
08-21-2003, 09:00 PM
Davis Id Like to do the 109 tests but that 190a9 test took a total of 4 hours It was very precision & it takes time to do each test perfectaly & monitor each flight the entire time


The great thing about this is I am now very comfortable reading the German Gauges Before I was only Good with the American gauges

guess Ill have to learn the Russian next but they seem to be the hardest

<center><FONT COLOR="white">ӚFJ-M œ R D ˜ ӡ[/i]</font>

<center> http://www.onpoi.net/ah/pics/users/ah_109_1059752328.jpg </center>

<center><FONT COLOR="white">The "Ace Edge"(c).
With my incremental trim
I am actually able to turn so quickly that, I never turn at all.
In Fact the Planet Earth rotates around the Axis of My PC, thus giving me the optimum turn rate and insuring that you
the bandit are promptly fraged !!!
In memory Of Ray R.I.P.[/i]</font>

XyZspineZyX
08-21-2003, 09:13 PM
These Numbers come from this websight:

Sea level: 575 km/h (585-595)
At 6,500 m: 675-680 km/h.
At 5500 m 690-700 km/h

At this time we are no where Close to achiving 690/700Kmh
@ 5000m Not according to the Cockpit Gauges anyway, also the Pit gauges corralate to the Speedbar readings NOT the fullscreen Gauges

Id also like to add that the tests In my Previouse post the RPM was 2700 using automatic PP in all flights/tests

<center><FONT COLOR="white">ӚFJ-M œ R D ˜ ӡ[/i]</font>

<center> http://www.onpoi.net/ah/pics/users/ah_109_1059752328.jpg </center>

<center><FONT COLOR="white">The "Ace Edge"(c).
With my incremental trim
I am actually able to turn so quickly that, I never turn at all.
In Fact the Planet Earth rotates around the Axis of My PC, thus giving me the optimum turn rate and insuring that you
the bandit are promptly fraged !!!
In memory Of Ray R.I.P.[/i]</font>

XyZspineZyX
08-22-2003, 12:12 AM
AFJ_Murdoc wrote:
- Id also like to add that the tests In my Previouse
- post the RPM was 2700 using automatic PP in all
- flights/tests
-

Even overreving the 190 with WEP and 100% pitch it takes a damn long time to overheat. That's probably why your testing took so long. 109s are much "easier" as far as overheating the engine goes.

--AKD

http://www.flyingpug.com/pugline2.jpg

XyZspineZyX
08-22-2003, 10:06 AM
Tenmmike,

All I have said is that I had read something about the thrust affect many years ago and that I no longer posses the material any longer.

I have also seen a film on the History Channel that was about the design and manufacture of the p51. It was the engineers and or test pilots in the film that made the claim of the cooling system producing thrust. I personaly have made no such claim.

I see no reason why the people in the film would lie or misslead about possible secrets that no longer need to be secrets.

I to have read those accounts about the pilots closing the radiators to gain speed. It is my understanding that when closed it is not completly closed and all airflow stopped. My understanding of aerodynamics tells me that due to the bournelli affect thrust and or increase of velocity and volume may possibly be produced.

What was not mentioned in the film was if the system was closed or open or some where in between when this so called thrust was produced.

Now it may not produce enough thrust in affect to push the aircraft but due to the use of the bournelli affect an increase of the velocity of the air passing through the cooling system may offset drag and in effect increase the potential airspeed over the use other cooling systems.

The two fastest aircraft generaly seen at the Reno Airaces are the Mustang and the Hawker Sea Furry. If you take a look at the Sea Furry and look at the FW190 you will see that both are very simular in apperance when comparing the cowling and exaust section.

There may be a very good reason for these aircraft to be as fast as they are and why they consistantly win races in unlimited competition.

I suggest we attempt to contact one of these aircraft owners and or crew chiefs to query them about this supposed thrust or perhaps balance of air flow through the cooling system. I state balance because a radiator causes drag but if aerodynamics are used to inrease the velocity and or volume of the air flowing through the cooling system the drag may be balenced out and negated or lessened.

People posting that this is bs and that is bs is totaly unproductive. As I am not aware of anyone in this forum that has any where near the credentials to make any such claim. I have nearly 40 years of flight experiance though do not posses the knowledge that could answer our questions. I am not about to discount something simply because it does not seem plausable. Mother Nature and Physics can be quite spetacular and with proper knowledge and application of intellegence one can certainly produce affects that defy common knowledge. Simply look at what has been achieved in the last 100 years.

I did find one film for sale on the History Channel website about the p51. I do not think this is the film that I saw that makes the referances to the thrust production.

http://store.aetv.com/html/catalog/vp01.jhtml?id=70713&browseCategoryId=


ReapALL

XyZspineZyX
08-22-2003, 01:11 PM
Hristos wrote:
- Thanks for the input !
-
- I did a quick test with Fw 190A-5, 100% fuel on the
- deck. After cycling several times through cowl flaps
- setting to make sure to clear the possible bug, it
- seemed that open cowl flaps take away some 35 kph of
- top speed on the deck.
-
-

If the A-5 looses some 35kph with the 'gill' flaps open, then there is something wrong. With an area of ~300cm^2, AND this is not the area presented to the airflow, then the cowl flaps on a/c such as the P-47 and La-5 should act as airbrakes when open. Anyone tested these a/c? Do not forget the other flaps on the Fw were behind the first flap. The oil cooler(radiator) did not have any flaps.

A front view of the Fw does not show the flaps protruding into the airflow, being blanked by the engines cowling.

http://www.stenbergaa.com/stenberg/crandall-stormclouds2.jpg

XyZspineZyX
08-22-2003, 02:42 PM
Good observations Milo.

XyZspineZyX
08-22-2003, 05:39 PM
Hristos wrote:

-
- It would be interesting to compare this speed loss
- to speed loss when carrying various ordnance. Didn't
- have time to do it yet though, sorry.
-
-

From Fw charts.

At 0.3km altitude, a 'clean' A-8 using 2100rpm did 515kph.

With the 300L drop tank on an ETC501 rack, the speed dropped to 485kph.

If as tested, that means the 'gill' flaps cause more drag than the droptank/rack combo.

http://www.stenbergaa.com/stenberg/crandall-stormclouds2.jpg

XyZspineZyX
08-22-2003, 05:51 PM
In my opinion, I think it should be noted (again) that these 'gill flaps' are not what is causing the drag, but as they are 'opened' (or 'closed', I don't know the correct terminology) the air is diverted over the engine, which is what is causing the excess drag. IMHO the drag has nothing to do with these 'gill flaps'. Just as the 109's 'flaps' or the P47's 'cowl flaps' are not the major contributing factor to drag (it is the air being redirected over radiators/engines/oil coolers).

XyZspineZyX
08-22-2003, 11:50 PM
MiloMorai wrote:
-
- Hristos wrote:
-
--
-- It would be interesting to compare this speed loss
-- to speed loss when carrying various ordnance. Didn't
-- have time to do it yet though, sorry.
--
--
-
- From Fw charts.
-
- At 0.3km altitude, a 'clean' A-8 using 2100rpm did
- 515kph.
-
- With the 300L drop tank on an ETC501 rack, the speed
- dropped to 485kph.
-
- If as tested, that means the 'gill' flaps cause more
- drag than the droptank/rack combo.

Before diverting the discussion away from the radiator bug further, I would suggest testing other aircraft and seeing if the drag effects of different radiator settings are consistent across the board. If all aircraft in the game get "too much" drag (unless we have some historical data, this will all be subjective) from opening cowl flaps, etc., then it's not really an issue worth pursueing. There are much more pressing bugs, modelling issues.

--AKD

http://www.flyingpug.com/pugline2.jpg

XyZspineZyX
08-23-2003, 01:53 AM
Ok here we go Very interesting.....


All Tests Used these settings:
Aircraft= FWA9
Prop Pth= Automatic
Throttle= 90%
Altitude= 5000m
Fuel = 100%
================================================== =========

Radiator= Default Position (IE:Automatic/Closed)
Wep = On
Max Kmh = 450
OilTemp = 100c

================================================== =========

Radiator= Manualy Selected= Automatic/Closed
Wep = On
Max Kmh = 410
OilTemp = 100c

================================================== =========

Radiator= Manualy selected= Open
Wep = On
Max Kmh = 410
OilTemp = 100

================================================== ==========

Radiator= Manualy selected=2
Wep = On
Max Kmh = 440
OilTemp = 118c

================================================== ==========

Radiator= Manualy selected=4
Wep = On
Max Kmh = 430
OilTemp = 116c

================================================== ==========

Radiator= Manualy selected=6
Wep = On
Max Kmh = 420
OilTemp = 113c

================================================== ==========

Radiator= Manualy selected=8
Wep = On
Max Kmh = 420
OilTemp = 110c

================================================== ==========



Ok again there is no differance Between Manualy Selected Auto/closed And Fully Open Radiator

There is a 40Kmh differance between Default Radiator setting (Auto/Closed) and Manualy Selected (Auto/Close)
there is no Oil Temp Change tho

It appears That The Default setting is bugged since there is a 40Kmh Advantage With no Oil tempature Rise !!!


End of Tests..... Conclusion Default Radiator setting Is bugged & needs fixing

This is not only On the FWA9 But On alot of the AC in FB but not all.....

Extensive testing needs to be done on All AC to isolate the effected AC, its not just on the FW, many other ac have same Issue, Its not my Job to test them all, Im just doing this one so that Oleg & 1C know there is a real problem/bug here.....


For any Laymen who donot understand what this means I shall spell it out...

It means that if I take a FW190a9 and do not manualy change my Radiator settings when I spawn. I will have a 40Kmh advantage over anyone who spawns into the game & manualy cycles his Radiator too the Auto/Closed Position with a FW190A9

Is that cleer enough LOL !!!



<center><FONT COLOR="white">ӚFJ-M œ R D ˜ ӡ[/i]</font>

<center> http://www.onpoi.net/ah/pics/users/ah_109_1059752328.jpg </center>

<center><FONT COLOR="white">The "Ace Edge"(c).
With my incremental trim
I am actually able to turn so quickly that, I never turn at all.
In Fact the Planet Earth rotates around the Axis of My PC, thus giving me the optimum turn rate and insuring that you
the bandit are promptly fraged !!!
In memory Of Ray R.I.P.[/i]</font>

XyZspineZyX
08-23-2003, 02:03 AM
ZG77_Lignite

Exactly what I was getting at. I do not believe the cowl flaps, gill flaps ect. are what is producing the most drag. But the managment of the air flow through the mediam that is
used to cool.

The key to a radiator and or any other device that needs to be cooled is surface area. The more surface area the more heat can be disapated. Take a look at some motorcycle
engines they have what is called a wrinkle coating to increase surface area to increase disapation of heat. The one problem with increasing surface area as in thicker, longer, taller radiator, wrinkle coating or additional material as in a heat sink, is additional drag.

The accepted rule is as speed increases wind resistance doubles. Therefore the more surface area that is contacted by the airstream the more resistance is increased and doubly so as speed increases.

Any engineer designing these aircraft would easily come to the conclusion that if cooling causes an inordinate amount of drag. Finding a solution that decreases drag and maintains cooling or improves cooling would produce a higher speed capability through the use of Higher horsepower settings and or improved aerodynamic properties.

An inovative approach may very well have been designed and implemented in the p51 and other aircraft. Since most people do not take the time to research small cogs in the big wheel of things. There could very well be some inovative properties that have been overlooked by the
masses.

A.K. Davis

I agree that it would be interesting to see if all aircraft are consistant. I also agree that there are more blaring bugs to be taken care of. Though this is also an important issuefrom a historical stand point and game play. As each planes ability to cool has a large impact on performance and certainly is a large part of what tatics are employed by the pilot.

To have all aircraft react identicaly or incorrectly to radiator settings takes away the individual charateristics of each plane and there capabilities.

The idea is disimular combat as it was in real life. Bringing out the charateristics of each aircraft I believe is a goal that should be pursued. It forces the pilot to know there craft and the enemies craft as success depends on it.

As an example for instance if a p51 in a prolonged fight is able to maintain a certain airspeed and keep cooling in check and an enemy aircraft must lower power settings and or
use cooling settings that induce more drag. The enemy aircraft will experiance a drop in attainable airspeed and or climb ability. This gives the p51 a marked advantage totaly attributed to a superior cooling system. To many times people refer to maximum speed attained by an aircraft, and most never refer to maximum maintained speed. Sprinting and staying in one piece for the long haul are two different things. Numerous p51 pilots have referred to running at a manifold pressure far above safe limits referred to in the
flight manual. This was all in the hope of getting a kill or surviving. This has been represented in the game by going to 110% throttle setting. The plane will overheat faster and or experaince a falure eventualy. Due to the cooling ability or durability of the individual aircraft all aircraft should mimic there real counterpart as closely as possible.


I know most online participants do not worry much about such as they usaualy go full boreto the nearest furball and die before there engine over heats. Those of use that also like to participate in coops that sometimes mimic real battles. Know the importance of having the cooling system react as close as possible as they did in real life. The charateristicsof the cooling system determines your ingress and egress tactics. This alone plays a largepart of how combat is engaged and disengaged. Even more so when flying jabo missions. Amount of flight time (fuel on board) and rate of climb attainable due to overheating or cooling some times also determined by distance to target. Makes all the differance in the condition of your engine when arriving on target. This ability to cool or lack thereof has a dramatic affect on the altitude one is able to obtain in a given distance. This also affects time and distance which is all important when cordinating multible attack groups.

From a furballers stand point cooling is a moot point. For those of us that relish all the real life hurdles that must be overcome welcome the complexity. This complexity
also adds to pilot overload which is a part of real life combat. Obviously those that were able to maintain SA while dealing with fine tuning the aircraft and employ successful
tactics are those that survived. Which is the point I am geting to. The pilot is more important than the aircraft and even more so when the real life advantages and disadvantages are as closely as posible followed in all the aircraft modeled.


ReapALL

XyZspineZyX
08-23-2003, 05:17 AM
ReapALL wrote:

-
- Exactly what I was getting at. I do not believe
- the cowl flaps, gill flaps ect. are what is
- producing the most drag. But the managment of the
- air flow through the mediam that is
- used to cool.
- The key to a radiator and or any other device
- that needs to be cooled is surface area. The more
- surface area the more heat can be disapated. Take a
- look at some motorcycle
- engines they have what is called a wrinkle coating
- to increase surface area to increase disapation of
- heat. The one problem with increasing surface area
- as in thicker, longer, taller radiator, wrinkle
- coating or additional material as in a heat sink, is
- additional drag.
-
-
- The accepted rule is as speed increases wind
- resistance doubles. Therefore the more surface area
- that is contacted by the airstream the more
- resistance is increased and doubly so as speed
- increases.
-
-
- Any engineer designing these aircraft would
- easily come to the conclusion that if cooling causes
- an inordinate amount of drag. Finding a solution
- that decreases drag and maintains cooling or
- improves cooling would produce a higher speed
- capability through the use of Higher horsepower
- settings and or improved aerodynamic properties.
-
-
- An inovative approach may very well have been
- designed and implemented in the p51 and other
- aircraft. Since most people do not take the time to
- research small cogs in the big wheel of things.
- There could very well be some inovative properties
- that have been overlooked by the
-
- masses.
-

Better do some more studying./i/smilies/16x16_smiley-wink.gif I give you a hint - low pressure.

http://www.stenbergaa.com/stenberg/crandall-stormclouds2.jpg

XyZspineZyX
08-23-2003, 05:50 AM
ReapALL wrote:
- A.K. Davis
-
- I agree that it would be interesting to see if
- all aircraft are consistant. I also agree that
- there are more blaring bugs to be taken care of.
- Though this is also an important issuefrom a
- historical stand point and game play. As each
- planes ability to cool has a large impact on
- performance and certainly is a large part of what
- tatics are employed by the pilot.

Oh, I agree whole-heartedly, but I believe there are priorities in the "improving the cooling system" process, which of course must also compete with other unresolved issues:

1. All radiator operation should be logical and consistent. There should be no artificial benefits or negatives to the automatic radiator system. Failing proper implimentation, the automatic system should simply be removed to make online play fair (and to make the affected aircraft behave in a "logical" manner).

2. Pre-mature or delayed overheating should be investigated in various aircraft to ensure that it is inline with historical performance. This requires documentation, not speculation.

3. Finally, after other issues are resolved, differential drag effects in various aircraft due to engine cooling systems should be investigated. This requires documentation, not speculation.

--AKD

http://www.flyingpug.com/pugline2.jpg