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jolulure
04-29-2006, 12:19 PM
http://forums.ubi.com/images/smilies/354.gifsorry to ask this question here... but I havent understand the rookies tutorials in the web... as I know you are aces http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif... what is the use of prop pitch??????? and the use of trims???? they just keep your plane centered, but they dont help moving or something like that...do they???? thanks for your valuable help http://forums.ubi.com/images/smilies/11.gif

Max.Power
04-29-2006, 01:12 PM
Prop pitch has different uses for different aircraft. There are several different mechanisms for prop pitch in this sim.

The most common by far is the constant speed propellor. It is present on most allied aircraft. The constant speed prop uses propellor pitch to control engine rpm. So for any powersetting, the propellor will try and keep the rpms stable. Alternatively, you can use the propellor pitch to control engine rpm. I have heard that engines function more efficiently at high throttle, so cruising at 85% prop pitch and 100% throttle will extend your flying time slightly.

One thing to remember is that course propellors create less thrust but less drag, and fine (100%) propellors create more thrust but more drag. So, if you want to slow down, ram the pitch up to 100% and throttle down. If your engine stops in mid flight and you want to try to glide home, push the prop pitch all the way to 0%. Similarly, if you're trying to get the maximum accelleration or maximum level airspeed out of your aircraft, keep the pitch at 100%.

BuzzardHead
04-29-2006, 01:43 PM
Think of prop pitch like the transmission in an automobile.100% being first gear,thus the lower the pitch the higher the gear.Use higher pitch to climb and take-off.Lower pitch to cruise and go fast.
As for trim,one trims his plane to smooth the airflow across flying surfaces to reduce drag and to keep his flight path straight.

NonWonderDog
04-29-2006, 02:31 PM
That's not exactly true, since the engine will in almost all cases make maximum power at 100% RPM. Usually the extra power is more than the extra drag created.

You get less power, but less drag, as you decrease RPM. You won't slow down much, but you'll use less fuel. In real aircraft you're instructed to decrease throttle first, because slowing the propeller by changing the blade angle while remaining at maximum throttle is very hard on the engine. That's not represented in the sim, so it actually leads to a bit of a speed boost with no danger if you yank the prop RPM down without touching the throttle.

But generally, high throttle, low RPM is preferred to low throttle, high RPM for fuel efficiency, in the case where both settings result in the same engine power. High throttle, high RPM will give the greatest engine output and should be fastest.

For landing you absolutely need to use 100% RPM, as it gives you more drag and lets you apply power faster in the case of a go-around. In fact, you're supposed to switch the FW-190 to CSP mode and use 100% for landings, rather than letting it spool down (if you've ever been frustrated with slowing the FW-190 down for landing, this is why). In the Me-109 it was supposedly common practice to use manual pitch control and maintain max allowable RPM during final approach.


As to how prop control applies to combat in a constant-speed plane... I've never really put much thought into it. Just leaving it at 100% and controlling your airspeed with the throttle should give you the most power and control. You'll probably dive a bit faster if you cut prop pitch, though.

jolulure
04-30-2006, 04:54 AM
Where can I buy those pedals??
How are they called???
Are they just from a racing wheel???
Cheapest price???

Bartolomeo_ita
04-30-2006, 05:35 AM
manual prop pitch is now arcade cuz someone cheated with it http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

jolulure
05-02-2006, 12:50 PM
whats feather prop???

Art-J
05-03-2006, 05:05 AM
When You turn off Your engine (or have it done by Your enemies http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif ), the prop freely rotates in the airstream and generates lots of drag (so called "windmilling"). Not a good thing, especially if You want to glide to the nearest flat field and crashland Your plane http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif. Even less good thing if You fly a multi-engine plane and only the prop at one side is windmilling. In order to reduce this effect You can "feather" the prop - rotate the prop blades so they are positioned parallel to the airstream and "cut" through the air like a knife, without generating any significant drag.

In our sim, only multi-engine planes can feather their props (except TB3 wich had fixed angle blades), You have to bind a separate key for that. When You use this function, a message "prop feathered" appears, although there is no corresponding animation in 3d model of Your plane.

Cheers - Art

Haigotron
05-05-2006, 12:02 AM
usually, when im diving, and dont want to increase the RPM, i usually drop the prop pitch to around 40 50%...

is this the usual method?

R988z
05-05-2006, 06:27 AM
are you sure it's only multiengined aircraft that can feather the prop? I know some can and some can't but I think I've been able to do it some single engined aircraft and not been able to do it in some multi engined aircraft, I'll have to check later.

Tully__
05-05-2006, 08:20 AM
On Trim:

An aircraft is a dynamic balancing operation. When an aicraft is in flight with constant power and neutral controls, it will tend to establish a flight path and stick to it. By design, that flight path is generally pretty close to straight and level and what the manufacturer considers suitable cruise throttle setting and altitude. At any other altitude or control settings it will tend to climb, descend and/or turn. In order to minimise pilot workload, trim controls are there to allow the pilot to retune the aicraft for different conditions so that he doesn't have to constantly hold the controls off centre if he chooses to fly the aicraft at other than "ideal" cruise power/altitude levels.

A further consequence of trim in aircraft like the WW2 combat aircraft we fly in this game. These aircraft are designed to operate over a very wide range of loads and speeds. In order to have control at low speed with heavy loads the control surfaces need to be fairly large. As a conequence, at high speed the airflow over the control surfaces resists movement away from centre to such an extent that pilots didn't have the strength to fuly deflect the controls at the upper limits of the aircraft's speed capabilities (generally in high speed dives was most noticeable). The trim controls allow the pilots to add a little aerodynamic assistance to their own strength (and in some aircraft a special trim tab was added to do this automatically) and help overcome these forces to (for example) pull out of a high speed dive. Except at very high speeds, trim will provide absolutely no manouvering advantage.

Where trim does provide a small but measurable advantage is in acheiving most efficient flight. The trim control is dead steady and so having your aicraft trimmed for level flight gives smoother and more efficient flight than just having the pilot manually adjusting (and constantly re-adjusting) for level flight. As a consequence, most pilots can (again for example) get a few km/h (mph, knots) extra in a maximum speed test using trim than they can just using the controls to manually fly straight & level.

Art-J
05-05-2006, 01:11 PM
Originally posted by R988z:
are you sure it's only multiengined aircraft that can feather the prop? I know some can and some can't but I think I've been able to do it some single engined aircraft and not been able to do it in some multi engined aircraft, I'll have to check later.

This is how it worked in one of the last versions of the game but... I didn't check it lately. Maybe it's been changed? (just like these funky fire extinguishers - planeset of crates equipped with them changes with every single patch! http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif).
On singles You can go down with "prop pitch" message all the way to "0%", but it actually means the lowest RPM (in CSP planes) or highest blade angle in German manual props, or both in German autos http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif
If You check it and find something interesting, go ahead and post it.

Cheers - Art

triad773
05-05-2006, 01:25 PM
Originally posted by jolulure:
Where can I buy those pedals??
How are they called???
Are they just from a racing wheel???
Cheapest price???

Pedals for aircraft there is pretty much only one player that I know of and thats CH. They are called Pro Pedals and I just got some. They really aren't hard to master tho it certainly does take some getting used to. Just practice. They are available on amazon.com for around $100 US. Don't think you are likely to find them cheaper unless you find them used some where. But they seem pretty well built, and I think they are worth the price. Really adds immerssion http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

Yeah re: prop pitch- I can only echo what others have already said; I have Ctrl P to increase prop pitch, Alt P to decrease. I always crank it up to 100% in combat, maybe 85% for cruising, and what ever the plane calls for while landing though I have generally opened the radiator and reduced prop pitch for landing so I can come in nice-and-sloooowwww.

Hope that helps.

Cheers

Triad

jolulure
05-05-2006, 01:37 PM
Thanks. las begginer question (hope it is!!!)http://forums.ubi.com/groupee_common/emoticons/icon_rolleyes.gif

Whats the use of the radiator?? I use it to keep my tempest out from overheats!!!

Crash_Moses
05-05-2006, 02:41 PM
Yep, that's exactly what it's for. It typically opens a duct to the engine to help cool it. On the B-25 you can see the cowls open as you open the radiator. Other planes it's on the bottom.

I usually open the radiator once I'm at cruise height to let the engine cool down a bit before I reach the target. There are a couple of downsides though. The radiator increases drag and will slow you down so you really want to close it before battle. Also, and I'm not sure if this is part of the damage model, but historically leaving the radiator open left your engine more prone to damage from flak and enemy fire.

Dean3238
05-05-2006, 05:14 PM
Whats the use of the radiator?? I use it to keep my tempest out from overheats!!!

From my experience it is an object that when filled with holes helps your engine sieze-up.

Appearently that is what it was designed to do. http://forums.ubi.com/images/smilies/winky.gif

Dean

jolulure
05-06-2006, 07:07 AM
Im very grateful!!! jejeje thanks!!! now, before you kill me, why when the fuel indicator says that the gallons are at 0 the engines dont stop??? I can stay with the engines on (after the indicator saying 0) like 10 minutes or so...

jolulure
05-07-2006, 04:05 AM
please answer!!

EiZ0N
05-07-2006, 05:46 AM
Maybe it's like how your car keeps running on empty for a little while

Daytraders
05-07-2006, 08:01 PM
Originally posted by Crash_Moses:
Yep, that's exactly what it's for. It typically opens a duct to the engine to help cool it. On the B-25 you can see the cowls open as you open the radiator. Other planes it's on the bottom.

I usually open the radiator once I'm at cruise height to let the engine cool down a bit before I reach the target. There are a couple of downsides though. The radiator increases drag and will slow you down so you really want to close it before battle. Also, and I'm not sure if this is part of the damage model, but historically leaving the radiator open left your engine more prone to damage from flak and enemy fire.

not sure if this is true but someone told me the other day that radiator closed or open makes no difference on the B25 can anyone confirm this, i know on other planes it also dont matter as it dont work. thx