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pauljguy
11-05-2008, 11:12 AM
I've always had a big problem with accuracy when shooting at planes while turning, and when the target plane has an "angle off" of 20 dgerees or more. It's has been difficult enough to apply the recommended lead compensation for a good deflection shot, and even using the recommended lead compensation, it never worked well when the target plane was jiggling around trying to spoil my shot.
Recently, it dawned on me that I was applying extra lead compensation, and it depended on my turn rate. I have tried to get data to show me how much lead compensation I need during turns. All I get is that I need a gyro compensating gunsight. Since I prefer flying in BF109's, I have to use a fixed gunsight - the REVI. As I had no data, I used the existing lead comensating gunsight and simultaneous fixed gunsight that is available in the "quick missions" and made up a table so that I can make an ESTIMATE of the correction.
Here's the data for a BF109-G2, at approximately 1000 meters altitude, guns are MG151/20 20mm, convergence is 300 meters (those guns don't need converging). The table is a function of speed (KM/hr) and maneuver. The correction is in units of "R", which is one large ring radius on the REVI sight.
"maxturn" is a very hard turn where the plane buffets hard, "niceturn" is the hardest smooth turn. "level" is correction in level flight, "maxslip" is flying full rudder, but in a straight line (to fool people on my six).

speed action level dive climb
250 maxturn 6R 4R 6-7R
niceturn 4R 3R 3R
level 1-2R
maxslip 6R

300 maxturn 6R 4R 6R
niceturn 3R 3R 3R
level 1R
maxslip 4R

400 maxturn 4R 4R 4R
niceturn 2R 2R 2R
level 0.2R
maxslip 4R

500 maxturn 3R 3R 2-3R
niceturn 2R 2R 2R
level 0R
maxslip 2R
The correction is such to ADD to your turn, climb or dive. In other words, if you turn right, you must move your crosshairs MORE to the right, or in a sudden nosedown, you must aim even further down.
There is a large degree of correction to be applied when the actual flight direction is different from where the plane is pointed. This happens in "dirty" configurations, with high turns, rudder, and slow speed climbs - all the stuff that happens when you are chasing a slow buy maneuverable plane (like those pesky I-153's). The corrections are huge! I often end up shooting blind, sometimes I have to use the identification text (when available) of the target plane as a reference, since the plane has slipped out of view.
For the same plane and guns, here are the compensations you need to accomodate the target planes "angle-off":

speed 0 10 20 30 45 90 deg. angle-off
250 0 0.4 0.7 1.2 1.5 2 R (radii-REVI)
300 0 0.5 0.9 1.3 2 2.5
400 0 0.6 1.2 2 2.5 3
500 0 0.8 1.5 2 3 3.5

You need to guess the angle-off of the plane, have an idea of the velocity, and then you have the lead needed for the deflection shot IF your plane is travelling in the direction of the gunsight. Then you must add the lead compensation from the first table. All that in a fraction of a second, so you can pull your cross hairs into the computed offset.
The BF109 is a difficult plane, since the high wing loading and low speed ability means the gunsight is seldom aligned with planes true motion.
It makes it very hard to down a wriggling target without losing about half your ammo!

-Paul

pauljguy
11-05-2008, 11:12 AM
I've always had a big problem with accuracy when shooting at planes while turning, and when the target plane has an "angle off" of 20 dgerees or more. It's has been difficult enough to apply the recommended lead compensation for a good deflection shot, and even using the recommended lead compensation, it never worked well when the target plane was jiggling around trying to spoil my shot.
Recently, it dawned on me that I was applying extra lead compensation, and it depended on my turn rate. I have tried to get data to show me how much lead compensation I need during turns. All I get is that I need a gyro compensating gunsight. Since I prefer flying in BF109's, I have to use a fixed gunsight - the REVI. As I had no data, I used the existing lead comensating gunsight and simultaneous fixed gunsight that is available in the "quick missions" and made up a table so that I can make an ESTIMATE of the correction.
Here's the data for a BF109-G2, at approximately 1000 meters altitude, guns are MG151/20 20mm, convergence is 300 meters (those guns don't need converging). The table is a function of speed (KM/hr) and maneuver. The correction is in units of "R", which is one large ring radius on the REVI sight.
"maxturn" is a very hard turn where the plane buffets hard, "niceturn" is the hardest smooth turn. "level" is correction in level flight, "maxslip" is flying full rudder, but in a straight line (to fool people on my six).

speed action level dive climb
250 maxturn 6R 4R 6-7R
niceturn 4R 3R 3R
level 1-2R
maxslip 6R

300 maxturn 6R 4R 6R
niceturn 3R 3R 3R
level 1R
maxslip 4R

400 maxturn 4R 4R 4R
niceturn 2R 2R 2R
level 0.2R
maxslip 4R

500 maxturn 3R 3R 2-3R
niceturn 2R 2R 2R
level 0R
maxslip 2R
The correction is such to ADD to your turn, climb or dive. In other words, if you turn right, you must move your crosshairs MORE to the right, or in a sudden nosedown, you must aim even further down.
There is a large degree of correction to be applied when the actual flight direction is different from where the plane is pointed. This happens in "dirty" configurations, with high turns, rudder, and slow speed climbs - all the stuff that happens when you are chasing a slow buy maneuverable plane (like those pesky I-153's). The corrections are huge! I often end up shooting blind, sometimes I have to use the identification text (when available) of the target plane as a reference, since the plane has slipped out of view.
For the same plane and guns, here are the compensations you need to accomodate the target planes "angle-off":

speed 0 10 20 30 45 90 deg. angle-off
250 0 0.4 0.7 1.2 1.5 2 R (radii-REVI)
300 0 0.5 0.9 1.3 2 2.5
400 0 0.6 1.2 2 2.5 3
500 0 0.8 1.5 2 3 3.5

You need to guess the angle-off of the plane, have an idea of the velocity, and then you have the lead needed for the deflection shot IF your plane is travelling in the direction of the gunsight. Then you must add the lead compensation from the first table. All that in a fraction of a second, so you can pull your cross hairs into the computed offset.
The BF109 is a difficult plane, since the high wing loading and low speed ability means the gunsight is seldom aligned with planes true motion.
It makes it very hard to down a wriggling target without losing about half your ammo!

-Paul

WTE_Galway
11-05-2008, 03:04 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by pauljguy:
I've always had a big problem with accuracy when shooting at planes while turning, and when the target plane has an "angle off" of 20 dgerees or more. It's has been difficult enough to apply the recommended lead compensation for a good deflection shot, and even using the recommended lead compensation, it never worked well when the target plane was jiggling around trying to spoil my shot.
Recently, it dawned on me that I was applying extra lead compensation, and it depended on my turn rate. I have tried to get data to show me how much lead compensation I need during turns. All I get is that I need a gyro compensating gunsight. Since I prefer flying in BF109's, I have to use a fixed gunsight - the REVI. As I had no data, I used the existing lead comensating gunsight and simultaneous fixed gunsight that is available in the "quick missions" and made up a table so that I can make an ESTIMATE of the correction.
Here's the data for a BF109-G2, at approximately 1000 meters altitude, guns are MG151/20 20mm, convergence is 300 meters (those guns don't need converging). The table is a function of speed (KM/hr) and maneuver. The correction is in units of "R", which is one large ring radius on the REVI sight.
"maxturn" is a very hard turn where the plane buffets hard, "niceturn" is the hardest smooth turn. "level" is correction in level flight, "maxslip" is flying full rudder, but in a straight line (to fool people on my six).

speed action level dive climb
250 maxturn 6R 4R 6-7R
niceturn 4R 3R 3R
level 1-2R
maxslip 6R

300 maxturn 6R 4R 6R
niceturn 3R 3R 3R
level 1R
maxslip 4R

400 maxturn 4R 4R 4R
niceturn 2R 2R 2R
level 0.2R
maxslip 4R

500 maxturn 3R 3R 2-3R
niceturn 2R 2R 2R
level 0R
maxslip 2R
The correction is such to ADD to your turn, climb or dive. In other words, if you turn right, you must move your crosshairs MORE to the right, or in a sudden nosedown, you must aim even further down.
There is a large degree of correction to be applied when the actual flight direction is different from where the plane is pointed. This happens in "dirty" configurations, with high turns, rudder, and slow speed climbs - all the stuff that happens when you are chasing a slow buy maneuverable plane (like those pesky I-153's). The corrections are huge! I often end up shooting blind, sometimes I have to use the identification text (when available) of the target plane as a reference, since the plane has slipped out of view.
For the same plane and guns, here are the compensations you need to accomodate the target planes "angle-off":

speed 0 10 20 30 45 90 deg. angle-off
250 0 0.4 0.7 1.2 1.5 2 R (radii-REVI)
300 0 0.5 0.9 1.3 2 2.5
400 0 0.6 1.2 2 2.5 3
500 0 0.8 1.5 2 3 3.5

You need to guess the angle-off of the plane, have an idea of the velocity, and then you have the lead needed for the deflection shot IF your plane is travelling in the direction of the gunsight. Then you must add the lead compensation from the first table. All that in a fraction of a second, so you can pull your cross hairs into the computed offset.
The BF109 is a difficult plane, since the high wing loading and low speed ability means the gunsight is seldom aligned with planes true motion.
It makes it very hard to down a wriggling target without losing about half your ammo!

-Paul </div></BLOCKQUOTE>


Surprising how much extra lead you need to pull. It is no wonder deflection shooting by guess work and "invoking the force" is rarely successful.

Do these tables work in combat ?

pauljguy
11-05-2008, 06:39 PM
These tables are derived from the games' aiming system. They are correct, BUT there are a few gotcha's. One major one is that there is about a second of delay. This is to simulate the LCOS (lead computing optical sight) used on the P51D. This is a problem...... I find that in a dogfight I'm better off estimating than using the LCOS. I'm told American flyers using the P51D gunsight had similiar feelings, but I have not used it long enough to give it a fair trial. Remember, that you still must use the corrections for angle-off even with the corrected gunsight.

The other problem is that the correction is not all that accurate, for my conditions with the BF109, my guess is +/- 25%. This is of course an estimation, and you're gonna have a lot of problems being accurate with the input parameters (speed, turn rate, guessing angle-off). My solution is to put the crosshair on the biggest offset, and sweep the bullets through to the minimum estimation. That's probably 1/4 to 1/2 seconds of fire.


I get some good practice with setting up a custom mission, with groups of enemy planes with no weapons. Set them to "ACE" level. They'll let you sneak up until about 300 meters, then they dive and wiggle all over the place. That's when you need the lead compensation. Use large enough ammo so you can see a hit, and try over and over to nail them in the dives and turns. They will conveniently resume their former course direction, so you won't lose them! I'm still not very good at it, as I stated before, it takes about half of a load of ammo to nail an I-16 or I-153. The faster planes in the full mission will just fly in circles, so if you have no ammo limit, you can just bang away 'til you figure the lead compensation out.

-Paul

M_Gunz
11-05-2008, 07:40 PM
Are you firing a single shot gun or an automatic weapon?

As the sight and target are moving towards each other, fire a tinch early and let the burst
be long enough to walk the target. Use your tracers or the impact of hits to correct your
aim except for snapshots where there is no time to correct aim.

There's a British WWII target lead mini-manual out and around that has all the angles and
pictures too.

One of the hardest things in IL2 is judging distances and speeds by view out to even 1km.
200+m is a good long way, even bullets take noticeable time to cross such distance.
If you knew how far the other is, how fast you and he are converging as well as the angles
then you'd know about where he will be in the short time it will take your shots to reach
the same place and if you're early 1/10 sec or so then the second or later bullets will
have the honor of perforating the prey.

When you are closing on or with a target, relative movement means the shot will hit when
he is closer than he was when you fired the shot -- the shot is effectively at shorter range.
So take you closing speed into consideration when deflection shooting as if the bullets are
sped up, you don't have to give as much lead when you are rapidly closing on the target.

Lastly -- firing steeply up or down, aim low. Gunsight view is as straight as light and
optics allow, bullet trajectories are not always so. Fired horizontally, bullet paths are
most affected by gravity and low and behold all the guns are arranged to fire across the
sight line when it is horizontal. Point up at 45 degrees and gravity only affects the path
about 70% as much, there's less drop and the bullet crosses the sight line closer in than
when horizontal. At 60 degrees gravity only affects the path half as much as level fire.

So you're zooming like a wombat in from above, there's two big reasons to use less lead than
you would in a horizontal situation at or near co-speed regardless of angles or distances.
If you're firing from far enough away that you can avoid ramming after shooting then that's
three reasons; the longer the range the more effect your difference in speed makes on shots.

Study your shooting using track playback, pause, POV to target, 1/4 speed, resume and learn.
You can pause and flip back and forth between cockpit and target to see the sight picture
and then move forward and see the tracers. Or practice with arcade=1 to see white dots as
positive proof of hits and where hit. Take the guesswork out of it.

Lurch1962
11-05-2008, 07:55 PM
I'm wondering why all this calculation is necessary. From my own in-game experience, how *my* plane is maneuvering has little to do with aiming for the shot. All that seems to be relevant is the *bandit's* motion with respect to me. I treat the situation at all times as though my plane is effectively at rest, and imagine where the bandit will have moved to during the interval between firing and impact.

After all, the speed of a bullet is around 800 m/s, while the *greatest* velocity component of my plane is the one directed longitudinally, at about 200 m/s. Any other velocity components--even during hard maneuvering--are of very much smaller magnitude.

Whether I'm in level flight or maneuvering hard at the moment of firing, once the round leaves the barrel (after a VERY small fraction of a second) it follows the same ballistic trajectory. And the extra velocity given to the bullets due to my forward speed is pretty much nullified by the bandit's own motion when I'm on or near his six. Only in cases where the aspect angle is approaching 90 degrees does the velocity differential becomes *slightly* significant. Certainly not to a degree requiring compensation that amounts to more than a small fraction of a gun sight's ring radius.

Have you used the 'freeware' Excel utility, "Sniper's Corner"? I've tried, but Open Office's spreadsheet application is not sufficiently compatible to show the graphic representation properly (dang!). I'd be really curious to see series of pictures generated by this neat utility, where the applicable variables in your thesis are tried.

K_Freddie
11-06-2008, 01:40 AM
The trick is to predict the flight path of the a/c, and let them fly through a shell stream. With practise you get to know when to fire.
Example one:- firing over the nose.
Picking a point somwhere near the flight path
http://www.vanjast.com/IL2Pics/LeadA0001.jpg
Firing
http://www.vanjast.com/IL2Pics/LeadA0002.jpg
Firing with control adjustments
http://www.vanjast.com/IL2Pics/LeadA0003.jpg
Waiting for the results - A hit barely visible
http://www.vanjast.com/IL2Pics/LeadA0004.jpg
final confirmation.
http://www.vanjast.com/IL2Pics/LeadA0005.jpg

Example 2: From the above attitude - pushing stick forward and using rudder.

Again - flight path point aiming
http://www.vanjast.com/IL2Pics/LeadB0001.jpg
Easier to witness events form this angle and make adjustments
http://www.vanjast.com/IL2Pics/LeadB0002.jpg
Another one bites the dust
http://www.vanjast.com/IL2Pics/LeadB0003.jpg

These are AI planes that you can practise on. Once you fly online your opponent is not so accommodating and changes his flight path regularly, making it difficult to aim. With a bit of patience a moment will come when they will fly like the AI for a second or 2 - this is when you strike - But do you have the time with so many others wanting to 'chop' you down... http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Edt: Another thing is that if you plan to eventually fly with 'full pit', don't practise in open pit mode as the visualisations and angles are different, causing you to miss very often. This can be quiet offputting.
http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

Crikey2008
11-06-2008, 07:41 PM
With all due respect...I wouldn't have pulled the trigger at the distances shown.

As shown they are at most between a 60% - 80% probability of destruction success.


fill the windscreen!...the closer you are the less delection calculation needed...and you will save a LOT of ammunition

K_Freddie
11-07-2008, 01:35 AM
http://forums.ubi.com/images/smilies/winky.gif No problem...
When you done this long enough, and in an a/c that has a shipload of ammo, and weaponery to down a starship in a single burst - why worry about losing a few shells here and there when you're know you're going to hit.

A bit of maths on the FW. Those bursts were about 1-2 seconds (average of 1.5secs). The FW has ammo on the outer cannon for about 20 seconds, inner cannon for about 40secs and MG stuff for ~60 secs.
So min time 20/1.5 ~ 12 aircraft to shoot down. It highly unlikely that one will ever do 12 a/c in one mission, so yeah... decorate the sky with some more tracers.. makes the opposition stress out. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Incidently I use about half my ammo just for this purpose - Not to hit but to make the other guy make a mistake. If I hit ..well that's good too.
http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

UgoRipley
11-09-2008, 03:09 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by M_Gunz:
...There's a British WWII target lead mini-manual out and around that has all the angles and
pictures too... </div></BLOCKQUOTE>
You're thinking of "Bag The Hun"?
Somebody even made a video out of that, with charachters !!

From the Banana forum:
LINK - http://forum.1cpublishing.eu/showthread.php?t=5012
VIDEO - http://weebitfilms.blogspot.com/2008/10/bag-hun-moviest...-il2-experiment.html (http://weebitfilms.blogspot.com/2008/10/bag-hun-moviestorm-and-il2-experiment.html)

pauljguy
11-09-2008, 11:12 AM
Most of the above responses rely on the deflection corrections provided by "bag the hun", the Horrido german document, and "Snipers Corner" excel spreadsheet calculations.

Unfortunately none of them mention how to deal with slip, slide, G forces and those effects where there is a difference between the planes direction of motion and direction its pointing in. These are problems when making a "snap shot", or when you are in a sharp turn, or when you are getting close to stall speeds. The above documents showing the required deflections are OK if you are "in the saddle" or have stabilized your plane and are about to calmly compose a firing solution.

My problem is that you don't always have optimum conditions to fire. For example, you had someone on your six, you just did a barrel roll with lots of rudder, and the attacker overshoots, he's now in front, BUT you are close to stall, and are trying to get a sight on him before he turns out of snap shot range. How much lead should you have that's ADDITIONAL to the deflection based on angle-off? In my BF109, if I'm at 300 KM/hr, performing a max turn, I need to add almost 6 diameters of the REVI ring!

One of the "good" things about doing the calculation in your head, is there isn't the delay present from the LCOS system. The gunsight on the P51D-20 has a delay. It shows you the bullet trajectory about 1 second ago, so you can sometimes have a problem chasing the pipper. That requires it's own special experience.

I searched all over for information on estimating lead compensation during high G maneuvres, and a few papers talk about it, nowhere did I find any data, or easy rules of thumb. Anyone have useful methods for guessing lead compensation for this condition, other than getting experience for hundreds of hours of target shooting?

Paul G.

K_Freddie
11-10-2008, 09:25 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by pauljguy:
Unfortunately none of them mention how to deal with slip, slide, G forces and those effects where there is a difference between the planes direction of motion and direction its pointing in. These are problems when making a "snap shot", or when you are in a sharp turn, or when you are getting close to stall speeds. The above documents showing the required deflections are OK if you are "in the saddle" or have stabilized your plane and are about to calmly compose a firing solution.

My problem is that you don't always have optimum conditions to fire. For example, you had someone on your six, you just did a barrel roll with lots of rudder, and the attacker overshoots, he's now in front, BUT you are close to stall, and are trying to get a sight on him before he turns out of snap shot range. How much lead should you have that's ADDITIONAL to the deflection based on angle-off? In my BF109, if I'm at 300 KM/hr, performing a max turn, I need to add almost 6 diameters of the REVI ring!

One of the "good" things about doing the calculation in your head, is there isn't the delay present from the LCOS system. The gunsight on the P51D-20 has a delay. It shows you the bullet trajectory about 1 second ago, so you can sometimes have a problem chasing the pipper. That requires it's own special experience.

I searched all over for information on estimating lead compensation during high G maneuvres, and a few papers talk about it, nowhere did I find any data, or easy rules of thumb. Anyone have useful methods for guessing lead compensation for this condition, other than getting experience for hundreds of hours of target shooting?

Paul G. </div></BLOCKQUOTE>

You're wasting your time with all this ... nobody in their right mind 'pulls out a calculator' to work out a shooting solution - unless you're in a submarine. JUST SHOOT... and see where the shells go, then compensate, and shoot a bit better next time.
If you're about to stall ease up a bit, and if you cannot follow the opponent in the turn... run like hell. After a bit of practise everything falls into place.
http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif
Edt: judging from your number of posts, I assume you're new to IL2. Don't panic about this... Every new guy 'pays their dues' in the form of being cannon fodder. Eventually you get sick of this 'status symbol' and down your first online a/c. From here there's no looking back... http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

Wildnoob
11-10-2008, 11:26 AM
hello!

by the way please, could anyone explain to me how use the K-14 gunsigth in the gyroscopic mode ?

I already read a lot of pilots reports saying that it give a great advantage in deflection shoot for the pilot who have it.

but I can't find how to use this edge. http://forums.ubi.com/images/smilies/disagree.gif

M_Gunz
11-10-2008, 05:16 PM
One other thing to account for while firing when banked over is bullet drop will be to the side
of the pipper instead of where the sight is aligned. In close it's moot, 1/4 second drop will
only be 1 ft, less than 1/3 meter but then most bullets won't make 200m in 1/4 second....

You're not a flying sniper except maybe with 37+mm the ROF is too slow to hose and snap shots
don't get time to correct, short burst is all you get.

Know the factors and study track playbacks, you'll see the outcomes of many target solutions
and may just get to know when not to fire at the very least. If you don't know the factors
then study all you want, maybe you'll learn anyway.

JRJacobs
11-10-2008, 08:07 PM
something i did for an earlier post
--------------------
Here's a quick guide to range estimation using the Revi gunsight

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">100 meters - 0 degrees up or down - on his 6 </div></BLOCKQUOTE>

1) Fighter Large - Hurri - Wing tips OUTSIDE of ring halfway to stadia line
http://my.core.com/~jrjacobs/Range/100m/100m-FL-Hurri-0deg-6oclock.jpg

2) Fighter Medium - La5, La7, Laggs - Wing tips right ON ring
http://my.core.com/~jrjacobs/Range/100m/100m-FM-La5_Lagg-0deg-6oclock.jpg

3) Fighter Small - i16 - Wing tips just INSIDE ring
http://my.core.com/~jrjacobs/Range/100m/100m-FS-i16-0deg-6oclock.jpg

4) Ground Attack - IL2 - Wing tips to END of stadia lines
http://my.core.com/~jrjacobs/Range/100m/100m-GA-IL2-0deg-6oclock.jpg

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">150 meters - 0 degrees up or down - on his 6 </div></BLOCKQUOTE>

1) Fighter Large - Hurri - Wing tips just OUTSIDE of 2nd stadia line
http://my.core.com/~jrjacobs/Range/150m/150m-FL-Hurri-0deg-6oclock.jpg

2) Fighter Medium - La5, La7, Laggs - Wing tips right ON 2nd stadia line
http://my.core.com/~jrjacobs/Range/150m/150m-FM-La5_Lagg-0deg-6oclock.jpg

3) Fighter Small - i16 - Wing tips just INSIDE 2nd Stadia line
http://my.core.com/~jrjacobs/Range/150m/150m-FS-i16-0deg-6oclock.jpg

4) Ground Attack - IL2 - Wing tips right ON ring lines
http://my.core.com/~jrjacobs/Range/150m/150m-GA-IL2-0deg-6oclock.jpg

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">200 meters - 0 degrees up or down - on his 6 </div></BLOCKQUOTE>

1) Fighter Large - Hurri - Wing tips just INSIDE of 2nd stadia line
http://my.core.com/~jrjacobs/Range/200m/200m-FL-Hurri-0deg-6oclock.jpg

2) Fighter Medium - La5, La7, Laggs - Wing tips right HALFWAY between 2nd and 1st stadia line
http://my.core.com/~jrjacobs/Range/200m/200m-FM-La5_Lagg-0deg-6oclock.jpg

3) Fighter Small - i16 - Wing tips just INSIDE 1st Stadia line
http://my.core.com/~jrjacobs/Range/200m/200m-FS-i16-0deg-6oclock.jpg

4) Ground Attack - IL2 - Wing tips just OUTSIDE of 2nd stadia line lines
http://my.core.com/~jrjacobs/Range/200m/200m-GA-IL2-0deg-6oclock.jpg

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">250 meters - 0 degrees up or down - on his 6 </div></BLOCKQUOTE>

1) Fighter Large - Hurri - Wing tips HALFWAY between 2nd and 1st stadia line
http://my.core.com/~jrjacobs/Range/250m/250m-FL-Hurri-0deg-6oclock.jpg

2) Fighter Medium - La5, La7, Laggs - Wing tips ONE THIRD WAY between 2nd and 1st stadia line
http://my.core.com/~jrjacobs/Range/250m/250m-FM-La5_Lagg-0deg-6oclock.jpg

3) Fighter Small - i16 - Wing tips barely OUTSIDE of 1st stadia line
http://my.core.com/~jrjacobs/Range/250m/250m-FS-i16-0deg-6oclock.jpg

4) Ground Attack - IL2 - Wing tips almost TO of 2nd stadia line lines
http://my.core.com/~jrjacobs/Range/250m/250m-GA-IL2-0deg-6oclock.jpg

all screen caps are from the program Sniper's Corner_2.xls by Bruno & Abraxa

JRJacobs
11-10-2008, 08:08 PM
and part two
---------------

Gunery 102 - Lead
Now it gets a little harder. Good news, bad news.

good news - doesn't mater the size of the plane.
bad news - you now need to compute TWO vectors that change with angle and speed

Good News first
note
your aiming at the junction of the wing and the plane
you're diving on the target at 45 degrees
you're diving from his 6 o'clock

i16 just beyond the 2nd stadia line outside the ring
IL2 just beyond the 2nd stadia line outside the ring
Pe2 just beyond the 2nd stadia line outside the ring

SEE same lead regardless of size
for lead size DOESN'T matter

1) i16 just beyond the 2nd stadia line outside the ring
http://my.core.com/~jrjacobs/Leads/275KpH/275KpH-i16-45deg-6oclock.jpg

2) IL2 just beyond the 2nd stadia line outside the ring
http://my.core.com/~jrjacobs/Leads/275KpH/275KpH-IL2-45deg-6oclock.jpg

3) Pe2 just beyond the 2nd stadia line outside the ring
http://my.core.com/~jrjacobs/Leads/275KpH/275KpH-Pe2-45deg-6oclock.jpg



45 degrees up or down - on his 6

1) 225 Kph - Junction 1/3 way between 1st and 2nd Stadia line outside of ring
http://my.core.com/~jrjacobs/Leads/225KpH/225KpH-45deg-6oclock.jpg

2) 250 Kph - Junction 2/3 way between 1st and 2nd Stadia line outside of ring
http://my.core.com/~jrjacobs/Leads/250KpH/250KpH-45deg-6oclock.jpg

3) 275 Kph - just past 2nd Stadia line outside of ring
http://my.core.com/~jrjacobs/Leads/275KpH/275KpH-45deg-6oclock.jpg

4) 300 Kph - Junction 1/2 way between 2nd and 3rd Stadia line outside of ring
http://my.core.com/~jrjacobs/Leads/300KpH/300KpH-45deg-6oclock.jpg



45 degrees up or down - He's at 7 o'clock of your pipper
Same distance

1) 225 Kph - Junction 1/3 way between 1st and 2nd Stadia line outside of ring
http://my.core.com/~jrjacobs/Leads/225KpH/225KpH-45deg-7oclock.jpg

2) 250 Kph - Junction 2/3 way between 1st and 2nd Stadia line outside of ring
http://my.core.com/~jrjacobs/Leads/250KpH/250KpH-45deg-7oclock.jpg

3) 275 Kph - just past 2nd Stadia line outside of ring
http://my.core.com/~jrjacobs/Leads/275KpH/275KpH-45deg-7oclock.jpg

4) 300 Kph - Junction 1/2 way between 2nd and 3rd Stadia line outside of ring
http://my.core.com/~jrjacobs/Leads/300KpH/300KpH-45deg-7oclock.jpg



45 degrees up or down - You're closing in 45 degrees from his flank (offset) - He's at 6 o'clock of your pipper
A word about offset (or Angle off Tail (AoT)) no mater what angle you approach at, if you make him fly through the center of your sight, offset is automatic
in these pictures - make the green line (his fuselage) intersect the center of the sight and offset is calculated

1) 225 Kph - Junction 1/3 way between 1st and 2nd Stadia line outside of ring
http://my.core.com/~jrjacobs/Leads/225KpH/225KpH-45above-45offset-8oclock.jpg

2) 250 Kph - Junction 2/3 way between 1st and 2nd Stadia line outside of ring
http://my.core.com/~jrjacobs/Leads/250KpH/250KpH-45above-45offset-8oclock.jpg

3) 275 Kph - just past 2nd Stadia line outside of ring
http://my.core.com/~jrjacobs/Leads/275KpH/275KpH-45above-45offset-8oclock.jpg

4) 300 Kph - Junction 1/2 way between 2nd and 3rd Stadia line outside of ring
http://my.core.com/~jrjacobs/Leads/300KpH/300KpH-45above-45offset-8oclock.jpg



Lead changes with speed and angle
here are some examples from different views all at 275Kph
http://my.core.com/~jrjacobs/Leads/45Offset/z275KpH-45offset-2oclock.jpg


http://my.core.com/~jrjacobs/Leads/45Offset/z275KpH-45offset-4oclock.jpg


http://my.core.com/~jrjacobs/Leads/45Offset/z275KpH-45offset-9oclock.jpg


http://my.core.com/~jrjacobs/Leads/45Offset/z275KpH-below45offset-10oclock.jpg


Hope some of this helps you to visualize WHERE you need to aim

all screen caps are from the program Sniper's Corner_2.xls by Bruno & Abraxa

VW-IceFire
11-10-2008, 09:58 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by pauljguy:
Most of the above responses rely on the deflection corrections provided by "bag the hun", the Horrido german document, and "Snipers Corner" excel spreadsheet calculations.

Unfortunately none of them mention how to deal with slip, slide, G forces and those effects where there is a difference between the planes direction of motion and direction its pointing in. These are problems when making a "snap shot", or when you are in a sharp turn, or when you are getting close to stall speeds. The above documents showing the required deflections are OK if you are "in the saddle" or have stabilized your plane and are about to calmly compose a firing solution.

My problem is that you don't always have optimum conditions to fire. For example, you had someone on your six, you just did a barrel roll with lots of rudder, and the attacker overshoots, he's now in front, BUT you are close to stall, and are trying to get a sight on him before he turns out of snap shot range. How much lead should you have that's ADDITIONAL to the deflection based on angle-off? In my BF109, if I'm at 300 KM/hr, performing a max turn, I need to add almost 6 diameters of the REVI ring!

One of the "good" things about doing the calculation in your head, is there isn't the delay present from the LCOS system. The gunsight on the P51D-20 has a delay. It shows you the bullet trajectory about 1 second ago, so you can sometimes have a problem chasing the pipper. That requires it's own special experience.

I searched all over for information on estimating lead compensation during high G maneuvres, and a few papers talk about it, nowhere did I find any data, or easy rules of thumb. Anyone have useful methods for guessing lead compensation for this condition, other than getting experience for hundreds of hours of target shooting?

Paul G. </div></BLOCKQUOTE>
And this is where the science of gunnery crosses into the art of gunnery. Sometimes its just a matter of "doing it in your head" and making a guesstimate based on prior experience. Make an assumption...pull the trigger. When you've done it for a few years like some of us have you have a pretty good idea whats going to happen next.

I'm a bit out of practice now so its not as good but for a while I knew if it was a likely hit or not. Practice offline against C-47s and focus on high angle deflection shots. Do it for half an hour....sleep on it. Do that a few more times. Then go online. It works for me...whatever it is...something in my head does lead calculations really well really fast and usually it does this best when I'm not thinking about it.

F19_Orheim
11-11-2008, 02:12 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Crikey2008:
With all due respect...I wouldn't have pulled the trigger at the distances shown.

As shown they are at most between a 60% - 80% probability of destruction success.


fill the windscreen!...the closer you are the less delection calculation needed...and you will save a LOT of ammunition </div></BLOCKQUOTE>

+1

conv 150-180 depending on ride

K_Freddie
11-11-2008, 02:28 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by F19_Orheim:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Crikey2008:
With all due respect...I wouldn't have pulled the trigger at the distances shown.

As shown they are at most between a 60% - 80% probability of destruction success.


fill the windscreen!...the closer you are the less delection calculation needed...and you will save a LOT of ammunition </div></BLOCKQUOTE>

+1

conv 150-180 depending on ride </div></BLOCKQUOTE>
The difference would be that you would still have to chase those planes around for a longer time, exposing yourself to danger.
Convergence was 150, giving an effective range of 300.
http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

M_Gunz
11-11-2008, 02:33 AM
When you do BnZ, you need to roll and turn so as not to ram the target and you don't wait
until you're 100m away before doing it either, not when you're closing at 100+ m/sec.

If you think that .50's or even .303 can't do the job on deflection past 200m... what can I say,
you just hang back around his six, pound that seat armor and keep thinking "weak bullets".
IRL a bit of perspex won't stop a 303 from ruining your whole day at 300m and a ways beyond.

F19_Orheim
11-11-2008, 04:16 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by K_Freddie:
The difference would be that you would still have to chase those planes around for a longer time, exposing yourself to danger.
Convergence was 150, giving an effective range of 300.
http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif </div></BLOCKQUOTE>

I don't chase.. I kill http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif