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Advina
11-30-2004, 07:37 PM
I am looking to learn how to fly using complex engine managment, but I know nothing about prop pitch, cowl flaps, radiators, etc. Can anyone recommend a good tutorial? I am not looking for anything too technical. More of a beginners' guide to get the basics.

GSNei
11-30-2004, 07:43 PM
Go here http://www.airwarfare.com/. Click on guides. A gret site with a lot of good stuff

ZG77_Lignite
11-30-2004, 11:15 PM
You might try here: http://people.ee.ethz.ch/~chapman/il2guide/cemguide/intro.htm

Nothing against the AirWarFare.com article (those guys do great work over their), but it makes some generalizations regarding 'prop pitch' that can lead to incorrect assumptions. Namely with regards to Constant Speed Props. It is very important to know what type of prop system your particular aircraft utilizes (Il2/FB/PF models at least 4, arguably 5 or 6). Most (meaning about 95%) of the aircraft in FB use a constant speed prop, so you may want to familiarize yourself with it (all American aircraft, for example). Feel free to ask more questions, the subject can be Complex (but it need not be).

MaxMhz
12-01-2004, 12:49 AM
Different plane react different http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif
best try it on level flight - constant speed
once you get there... try changing prop pitch http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif
remember to do that a lot at different speeds in as many planes you can... some will blow up if you do... others are gentle http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

FACTS
- when using prop pitch 0% it will behave as an "air-brake"
- for some planes 100% prop pitch does not give you 100% effectiveness...
- the higher you go the lower the mixture
- the higher you go the higher the supercharger stage
- every plane is different
- Radiator - will slow speed and cool engine (at ANY speed)
- Radiator = cowl flaps lol
- Flaps will reduce speed and induce lift (will JAM if too fast or break off)
- And then there were airbrakes too http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif lol
- and Carriers
- and - depending on the plane - there are 3 different types of prop-pitch http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif
- and i even didn't mention take-off lol

for short - just fly http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

EURO_Snoopy
12-01-2004, 01:50 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by ZG77_Lignite:
You might try here: http://people.ee.ethz.ch/~chapman/il2guide/cemguide/intro.htm

Nothing against the AirWarFare.com article (those guys do great work over their), but it makes some generalizations regarding 'prop pitch' that can lead to incorrect assumptions. Namely with regards to Constant Speed Props. It is very important to know what type of prop system your particular aircraft utilizes (Il2/FB/PF models at least 4, arguably 5 or 6). Most (meaning about 95%) of the aircraft in FB use a constant speed prop, so you may want to familiarize yourself with it (all American aircraft, for example). Feel free to ask more questions, the subject can be Complex (but it need not be). <HR></BLOCKQUOTE>

It would be great if you can tell us more about the use of prop pitch and the differences between prop systems. MaxMhzs' points are a good start. I think this topic would be a good addition to the guide.

Tully__
12-01-2004, 03:43 AM
Snoop, a good place to start for "real world" prop advice for the beginner/intermediate sim pilot is John Deakin's Those Marvelous Props (http://www.avweb.com/news/columns/182082-1.html) article at AVWeb. If you check out the "Engine Related Columns" box down the right side of his Pelican's Perch Columns (http://www.avweb.com/news/columns/182146-1.html) index there are a bunch more real world articles on CEM many of which make references directly relevant to warbird flying.

Breeze147
12-01-2004, 05:57 AM
One thing: If your at a pretty high altitude and have changed your turbocharger and mixture settings change them back if you go diving down on enemies at a lower altitude or you will blow up your engine.

I'm still having trouble recognizing the difference with a constant speed prop. I'm really not sure what that means. Does it mean you can't change the settings? In the P-38J for example, you can change the settings, but I really don't notice a difference. I thought that if an aircraft did not posess a particular property, you couldn't change the settings. Did I make that confusing enough?

ZG77_Lignite
12-01-2004, 09:58 AM
Constant Speed Props (CSP from here on out) can seem hard to understand, but they are really quite simple and effective (thats why they were the most modern and effective prop in the 1940's, and are still so today).

I'll try to explain below, but remember, the terms used in the game (such as 'automatic', 'manual', 'prop pitch') are all generic terms intended to encompass many different actions; they had to use some words, and these are the ones they chose, but they can be confusing. I will try to use 'quotes' to signify FB sim terms, and leave real world terms natural.

Simply put, a CSP automatically adjusts itself to maintain highest efficiency/effectiveness for any given speed (in the real world they have limitations, in Il-2FB they are very generous and have few limitations). The 'pilot' (or player) cannot directly control the propellers blade angle (see the Bf-109 in 'manual mode' for a directly controlled blade angle system), which is why the control itself is (in real life) normally called an RPM Lever.

What the pilot Does control is the RPM of the engine (in both real life and FB/PF). Aircraft engines (both real and in FB) are designed to output maximum horsepower at maximum RPM. In FB/PF, this is known as '100% pitch', please note the confusing term 'pitch', it has nothing to do with blade angle (for CSP) but refers only to engine horsepower output (specifically engine RPM). So to go fast (combat, climb, ready power for carrier 'go-around') one would want the engine running at maximum RPM (remember the CSP automatically adjusts itself to operate at its best, to maintain that RPM), for cruising (fuel conservation, engine cooling, engine maintenance) lower settings can be used (much lower in fact).

There are also other systems in the game which I won't go into right now, such as; the 'Kommandergerat' of the FW190, which uses a combination CSP and throttle control (one lever control, acts as normal CSP in 'manual'); the 'Simple Variable Pitch' of the Bf109, Bf110, IAR80 etc, which uses a directly controlled propeller blade pitch mechanism that has an automatic control system (thus its 'automatic' and 'manual' modes); the Spitfire, which uses a 'linked' RPM and throttle control (very similar to FW190 in FB/PF, acts as CSP in 'manual' mode); the TB3, P.11c, etc, which uses a Fixed prop (the simplest of all, it has no blade pitch adjustments, and operates like your lawn mower engine).

There are many others that can probably state this much more clearly than me (they have done so in the past, Michapma, Effte), but in their abscence I will endeavor to help out, as best I can.

effte
12-02-2004, 07:57 AM
Nothing to add, really (but thanks!), except that:

€ Lignite has a very good grasp on things
€ 100% RPM (prop pitch, in the game) will slow you down the fastest. This has been verified in Il-2 through test flights.
€ RPM is not output power. However, at the maximum torque maximum RPM will give you maximum shaft power. For a power reference, use MAP.

Have a look at Mike€s (michapma€s) guide to CEM, posted above by Lignite. He€s doing a great job!

Regards,
Fred

Advina
12-02-2004, 09:51 PM
Thanks for the help folks. I imagine this will take some time.