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ceswiedler
07-16-2007, 10:56 AM
WHy is it that the cockpit compasses are (to my eye) backwards? I'm sure this is a historically accurate feature of IL-2, but I can't figure out why on earth they're that way. When I'm on heading 270, I expect the compass to show 180 to the left of the needle, and when I turn left I expect the compass to rotate right until the needle points to 180. Instead, it seems to do the exact opposite--180 is to the right, and when I turn left, the compass turns left as well. I end up using the speedbar for heading, which is useful but doesn't give the same sort of directional feeling as a compass.

I don't have IL-2 in front of me at the moment, so maybe I'm remembering it wrong, but playing last night at least I was continually feeling like the compass was doing the opposite of what I expected. Is there a different way of 'looking' at the compass--do I have the wrong point-of-view in my head? I don't suppose there's any option to reverse the compasses...

ceswiedler
07-16-2007, 10:56 AM
WHy is it that the cockpit compasses are (to my eye) backwards? I'm sure this is a historically accurate feature of IL-2, but I can't figure out why on earth they're that way. When I'm on heading 270, I expect the compass to show 180 to the left of the needle, and when I turn left I expect the compass to rotate right until the needle points to 180. Instead, it seems to do the exact opposite--180 is to the right, and when I turn left, the compass turns left as well. I end up using the speedbar for heading, which is useful but doesn't give the same sort of directional feeling as a compass.

I don't have IL-2 in front of me at the moment, so maybe I'm remembering it wrong, but playing last night at least I was continually feeling like the compass was doing the opposite of what I expected. Is there a different way of 'looking' at the compass--do I have the wrong point-of-view in my head? I don't suppose there's any option to reverse the compasses...

Fireball_
07-16-2007, 11:39 AM
Instead of thinking in terms of the compass turning this way or that, think of the compass as remaining stationary in the sky and your plane moving around the compass as you turn. And this is really what is happening.

I get confused myself. Sometimes when I've drifted off heading a bit and correct, I correct the wrong way and make it worse.

ceswiedler
07-16-2007, 01:43 PM
But that's just how I think about it... I think to myself, "heading X is to the left of the needle, if I turn left, it will remain where it is, and I'll rotate to it, and so from my cockpit perspective it will look as if it's rotating to the right." But (I'm pretty sure) that's not what happens. Can anyone confirm?

berg417448
07-16-2007, 02:07 PM
This is going to be difficult for me to explain but I will try to see if i have the vocabulary to make sense.


It is because the number display you are reading is on the back side of the compass as you look at it....not the front.

I'm flying 120 degrees. I want to turn left to due East.
http://www.airworlduk.com/falcon/mcpan.jpg

As I turn left towards East the compass should be thought of a sitting still. The line must be thought of as the plane sliding around the outside of the compass. Therefore East is going to be to the right as I view it.

Crash_Moses
07-16-2007, 02:40 PM
You need this!

An offical Crash Moses Compass Rose. Available while supplies last...

http://i4.photobucket.com/albums/y125/Crash_Moses/PBJCompassRosebig.jpg

ceswiedler
07-16-2007, 06:17 PM
So is the compass a vertical disc which rotates around an axis which goes forward into the dashboard and nose of the plane (which is what your picture looks like)? Or is it a flattened cylinder rotating on a axis which goes up-and-down between the floor of the cockpit and the canopy (which is what I thought it was)?

MaxMhz
07-16-2007, 08:44 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Crash_Moses </div></BLOCKQUOTE>
geesh Crash_Moses...
Don't you have a bigger one?
Ever heard about links or resize??

Crash_Moses
07-16-2007, 09:32 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by ceswiedler:
So is the compass a vertical disc which rotates around an axis which goes forward into the dashboard and nose of the plane (which is what your picture looks like)? Or is it a flattened cylinder rotating on a axis which goes up-and-down between the floor of the cockpit and the canopy (which is what I thought it was)? </div></BLOCKQUOTE>

It depends on the airplane. Some have a regular dash board type that sits vertically on the instrument panel and some have the cylindrical version which lays flat and is recessed into the instrument panel. Some have both.

Fun Fact #1: The actual compass for most airplanes was located aft in the fuselage and constituted a gyroscope sealed in a box. This was connected either electrically or pnuematically to the instruments in the cockpit.

Fun Fact #2: As technology improved during the war it became possible for pilots (specifically bomber pilots) to land their aircraft using instruments only by using their compass and radio beacons to find the runway. Mid and late war qaulification on these new systems consisted of taking off and landing (safely) five times with absolutely no view outside the aircraft.

I wish real world navigation was simulated in IL-2 a little better. That's one reason I made the compass rose. I like to fly full-real and navigation is a pain without some kind of reference (especially on-line). I use it to plot my course and as a general reference for finding my way back to base. And if you laminate it, it makes a great coaster...

S!

Padser
07-17-2007, 03:10 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">

I get confused myself. Sometimes when I've drifted off heading a bit and correct, I correct the wrong way and make it worse. </div></BLOCKQUOTE>

~S~

It does my head in as well - just remember that as you turn left the numbers should get smaller and as you turn right they should get bigger - it's a way of checking your compass is working as you taxi out to the runway in real life.

TTFN

Pads

Skunk_438RCAF
07-17-2007, 06:24 AM
You have to see the difference between a gyro compass, which is going to look like the rest of your instruments, where the dial stays stationary and you have a needle pointing to your heading(sometimes the needle is stationary and the dial turns), and a true magnetic compass, like the one berg is showing you.

Magnetic compasses always always point NORTH. As berg explains you are reading the back of the compass disc, which may look backwards to you, but in reality its not. One thing that happens with these compasses is that they need to be horizontal in order to give you a correct reading. If you bank they will exhibit strange behaviour, like turning the opposite way, but when you return to wings level, the compass should swing to its proper heading. The thing is that as a pilot, you have to know that 180 is left of 270, so if you see the magnetic compass swinging the wrong way, dont worry because you KNOW that its swinging the wrong way while your are in your turn.

Hope some of this helps.

buzzsaw1939
07-17-2007, 09:53 AM
Theres no easy way to explain compasses, without pictures, if you look at Berg's pic, the numbers that you see, are the numbers on the outside of Crashe's rose, print it, study it, and you'll get it! http://forums.ubi.com/images/smilies/25.gif

Crash_Moses
07-17-2007, 11:08 AM
Right on!

Here's a smaller one I made for someone with the Corsair instead of the PBJ. I apologize for not having a larger version which, of course, prints out much nicer. Of course, you can always take the big one and put your favorite plane in instead.

Like I said, this one doesn't print out as nice but it's still legible if you print it out big enough.

http://i4.photobucket.com/albums/y125/Crash_Moses/CorsairCompassRose.gif

ddsflyer
07-17-2007, 11:31 AM
The standard magnetic compass is such a miserable navigational instrument that all it is used for is setting the gyro compass to correct for precession. A while back a company named Hamilton created a vertical card compass that reads just like a standard vertical face gyro compass. This was and is a major improvement over the old. Enough so, in fact, that flying after a gyro failure (or simulated one) is very much easier. The old compasses were filled with kerosene to dampen out oscillations of the pivoting element. If they leaked, and they often did, you could smell the leak. The Hamilton compass uses magnetic damping and is much more stable.

ceswiedler
07-17-2007, 12:01 PM
OK, I think I get it now. The needle is pointing out from the center of the compass, i.e. down. I suppose I can get used to that.

My next question is why on earth did they do it that way? If they flipped the compass over so that the needle was effectively pointing up (so instead of seeing the bottom of the compass, we see the top), it would be MUCH more intuitive--you would turn your plane in the direction of the indicated heading, instead of away from it.