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Help and Support Forums => Help and Training => Topic started by: Raven3 on May 15, 2014, 10:55:56 AM

Title: Convergence
Post by: Raven3 on May 15, 2014, 10:55:56 AM
What distance do most folks set their gun convergence for.  If it makes a difference, say in a P51D.
Title: Re: Convergence
Post by: The Fugitive on May 15, 2014, 10:58:39 AM
Set it where you find yourself shooting. Check your films to see what range you fire at. I set mine at 300 in most 50 Cal planes.
Title: Re: Convergence
Post by: ImADot on May 15, 2014, 11:06:38 AM
I usually have mine set between 250 and 350, depending on the plane, the ammo type, and the mission profile (bomber hunting or dogfighting).

Here's a graphic to describe what convergence looks like for wing-mounted guns:
(http://i289.photobucket.com/albums/ll239/ViperDriver/AcesHighII/convergence_zps91cb558d.jpg) (http://s289.photobucket.com/user/ViperDriver/media/AcesHighII/convergence_zps91cb558d.jpg.html)
Title: Re: Convergence
Post by: Lusche on May 15, 2014, 11:28:19 AM
I have my convergences set on all planes at 350 (except Me 262 and Hurri/Spit I).
I would advise against changing convergence back and forth between missions, or even against different convergence settings for the same weapon type on different planes. Each time you have to adjust your inner sight picture, and the benefits are probably quite limited under most circumstances (unless you are a very good shooter that can cope with that).

Often I read questions like "whut best conv for Pony... and whut for Jug?". Seems some players may think of convergences as a kind of magic trick... just find the magic setting and you will rake up kills like crazy. Unfortunately it doesn't work like that. A happy medium setting (default?) is probably the best all round. If you want to fiddle with your convergence settings, I'd suggest you film a lot of your combats and see at which distances you are actually shooting the most at, and adjust your settings from that individual perspective.
Title: Re: Convergence
Post by: Rogue9Volt on May 15, 2014, 11:46:29 AM
In a plane with .50's I usually set convergence to 250 or 300 yds.  With 20mm cannons, I usually set 200 and get closer before shooting.  I don't use 30mm or above because I can't aim those taters for crap...  :devil
Title: Re: Convergence
Post by: Wiley on May 15, 2014, 11:53:31 AM
I set everything to 300 except the tater chucker in the 109s, which I set to 350 because it seems to stay close to the pipper for the greatest amount of time without going too far above or below.

The 262 I set one pair to 200, the other to 400 to give me a spread of 30mm as opposed to everything converging on a point.

Wiley.
Title: Re: Convergence
Post by: Randy1 on May 15, 2014, 12:05:41 PM
I have mine set on 350 for 50s on the P47s and for the canon and 50s on the P-38.

Lusche made a point about sticking with the setting of your choice.  Sound advice.

Go to offline practice and type in /.target 350 .  Go to the NE runway and you will see a target.  I use 350 as an example.  Try other distances as well.  The / calls up the text buffer.
Title: Re: Convergence
Post by: FLS on May 15, 2014, 12:47:07 PM
What distance do most folks set their gun convergence for.  If it makes a difference, say in a P51D.

For convergence 300 is a good starting point. If you find over time that most of your shot opportunities are closer or further away you can change it.

When offline or in the TA you can use a target to see your convergence and dispersion. Use the dot command ".target 300" to set a floating target 300 yards N of you. Set .target 100 for example to see how your 300 yard convergence prints at closer range and .target 600 to see it at long range.  Use .target 0 to turn the target off.
Title: Re: Convergence
Post by: The Fugitive on May 15, 2014, 12:54:04 PM
Wow double post!
Title: Re: Convergence
Post by: TonyJoey on May 15, 2014, 01:28:50 PM
I set my convergence on the .50s to 500 to get the guns pointed up a little bit and help with lead. This will particularly come in handy when you quickly drop on an opponent and he does a break turn. You don't have to pull as much lead and can shred them pretty quickly with 6 .50s with their whole plane in view.
Title: Re: Convergence
Post by: FLS on May 15, 2014, 01:58:28 PM
I set my convergence on the .50s to 500 to get the guns pointed up a little bit and help with lead. This will particularly come in handy when you quickly drop on an opponent and he does a break turn. You don't have to pull as much lead and can shred them pretty quickly with 6 .50s with their whole plane in view.


If you set a target at 250 yards you can see the difference in required lead. I don't believe our rounds go over the sight line enough to make a difference.


Raven this shows a P-51 full size on the target. It may help you evaluate your pattern. I believe each circle increases the radius 10 ft.

(https://www.mediafire.com/convkey/e71f/ghobfv373t2d7cj4g.jpg) (http://www.mediafire.com/view/ghobfv373t2d7cj/P51targetview.jpg)
Title: Re: Convergence
Post by: Oldman731 on May 15, 2014, 03:23:07 PM
Raven this shows a P-51 full size on the target. It may help you evaluate your pattern. I believe each circle increases the radius 10 ft.


Great image.  Is that at 250 yards?

- jkw

Title: Re: Convergence
Post by: FLS on May 15, 2014, 03:43:13 PM

Great image.  Is that at 250 yards?

- jkw


I set the target at 1 yard and zoomed out in F3 for a screenshot.
Title: Re: Convergence
Post by: Raven3 on May 15, 2014, 03:50:06 PM
Thanks guys. I appreciate the info.
Title: Re: Convergence
Post by: ink on May 15, 2014, 03:54:58 PM
some have said it...but I will say it again because it is THE most important part of landing KILLING hits....land your hits at the convergence....

also...Aim for the pilot...

there is an old saying "aim small...miss small"

killing the pilot is an insta explosion....done deal....and you see a nice little Death animation :devil

Title: Re: Convergence
Post by: Ack-Ack on May 15, 2014, 08:44:45 PM


also...Aim for the pilot...


Personally, I advise aiming for the wing root area as it's the area on the plane where you're more likely to get a catastrophic hit on the first burst, and at the least a critical hit like flight surface damage or wounding the pilot.  It also provides a larger area to aim for than the cockpit.

ack-ack
Title: Re: Convergence
Post by: Raven3 on May 16, 2014, 07:32:11 AM
Personally, I advise aiming for the wing root area as it's the area on the plane where you're more likely to get a catastrophic hit on the first burst, and at the least a critical hit like flight surface damage or wounding the pilot.  It also provides a larger area to aim for than the cockpit.

ack-ack

Well, right now I'm lucky if I can hit the ground.  :)
Title: Re: Convergence
Post by: Rogue9Volt on May 16, 2014, 03:05:55 PM
Well, right now I'm lucky if I can hit the ground.  :)

Have you gone in the TA and played with the Lead-computing-gun-sight?  It's very easy to use, and will show you where to aim.  I like to pop in there and use it for a half hour or so every couple of weeks, to remind myself how much lead to pull.

In the TA, you hit Ctrl-tab to turn on friendly targeting.  Then hit the tab key to target the pane in your view.  Then it places cross hairs out in front of the targeted aircraft to show you where to shoot in order to hit the target.
Title: Re: Convergence
Post by: ink on May 16, 2014, 07:42:01 PM
Personally, I advise aiming for the wing root area as it's the area on the plane where you're more likely to get a catastrophic hit on the first burst, and at the least a critical hit like flight surface damage or wounding the pilot.  It also provides a larger area to aim for than the cockpit.

ack-ack

 :P

I like the explosion  :D
Title: Re: Convergence
Post by: mtnman on May 18, 2014, 07:15:31 AM
I set my convergence on the .50s to 500 to get the guns pointed up a little bit and help with lead. This will particularly come in handy when you quickly drop on an opponent and he does a break turn. You don't have to pull as much lead and can shred them pretty quickly with 6 .50s with their whole plane in view.


This "technique" doesn't work as you suggest; at least not on wing mounted guns (including the 50's).

Setting your convergence for 500 yards doesn't "get the guns pointed up a little bit"; it actually gets the guns pointed DOWN a little bit, so works contrary to your stated intent.

To point your guns up a little, it's necessary to bring your convergence point IN.


Title: Re: Convergence
Post by: mtnman on May 18, 2014, 07:25:31 AM
I don't believe our rounds go over the sight line enough to make a difference.

They definitely do go (or have the ability to go) well over the sight line.  The in-game balistics are not dependant upon the sight line, but rather behave much more realistically.

Many of our notions regarding the sight line (LoS) are based on our knowledge of how bullets behave compared to the LoS with rifles, etc (which most / all of us are more familiar with on a hand's-on basis). 

With wing-mounted guns the bullets behave the same as rifle bullets, but the end result is massively altered by the pilot's LoS compared to the rifle shooter's LoS.  With a rifle, the LoS is only an inch or two from the level of the barrel.  With wing-mounted guns, the LoS is MUCH higher; nearly 60" above the barrels in a plane like the F4U.

With a rifle sighted in a 300 yards, the bullets will be hitting 3ft or so LOW at 600 yards (just a rough estimate, I haven't consuled my charts recently). 

With wing mounted guns in an F4U sighted in at 300 (300 yard convergence), the bullets will be striking 4-5' HIGH at 600 yards.
Title: Re: Convergence
Post by: Raven3 on May 18, 2014, 08:04:46 AM
Have you gone in the TA and played with the Lead-computing-gun-sight?  It's very easy to use, and will show you where to aim.  I like to pop in there and use it for a half hour or so every couple of weeks, to remind myself how much lead to pull.

In the TA, you hit Ctrl-tab to turn on friendly targeting.  Then hit the tab key to target the pane in your view.  Then it places cross hairs out in front of the targeted aircraft to show you where to shoot in order to hit the target.

Thanks. I will sure give that a try.
Title: Re: Convergence
Post by: Patches1 on May 18, 2014, 09:18:27 AM
"...What you see is what you get..."

This quote is how I set my convergence nearly ten years ago...and I still fly with the same convergence with all guns and cannons. Yep! I don't change my convergence for anything.

Why? Well, I just got used to the convergence settings and adjusted my flying from there. There is no "magic convergence" that will give you sure kills each and every time you shoot in each and every situation, but good Situational Awareness, Basic Flight Maneuvers, and Air Combat Maneuvering will give you good firing solutions if you learn to fly and recognize good shot opportunities whilst knowing the sight picture of your convergence setting.

To put this simply, in order to shoot anyone down, regardless of your convergence setting, you must first out fly them! It is really that simple. No matter what convergence you set for cannons, or guns, you must first out fly your opponent before you can employ your weapons.

Earlier I mentioned knowing what your sight picture was for your convergence setting; this is where you and your convergence setting must become one. You must learn what the optimum picture looks like, and what the marginal picture looks like, and by doing so you learn to fly your aircraft to its convergence, rather than flying an aircraft with guns, or cannons set at a convergence and then firing.

Well, what about mixed weapons systems, guns and cannons on the same aircraft? No matter, I set them all for the same convergence. It's really all about flying and how you fly to bring your weapons to that optimum sight picture at your selected convergence.

My convergence setting is 275, for everything. No matter what aircraft I fly, no matter what weapon system the aircraft has, 275 is my convergence setting, and I will learn to shoot down opponents at that setting. Learn to fly the aircraft at its convergence, rather than learning to fly the aircraft, then learning the guns at convergence, then learning the cannons at convergence, then learning to fly the aircraft to the guns convergence and then to the cannon convergence and then to the mixed gun and cannon convergence and then learning all of the differing convergences you set for various aircraft.

And, yes, I shoot down bombers with my 50 cals set at 275... I've shot down lots of bombers!

Pick a convergence setting and learn to fly to it.






Title: Re: Convergence
Post by: FLS on May 18, 2014, 10:19:02 AM
They definitely do go (or have the ability to go) well over the sight line.  The in-game balistics are not dependant upon the sight line, but rather behave much more realistically.

Many of our notions regarding the sight line (LoS) are based on our knowledge of how bullets behave compared to the LoS with rifles, etc (which most / all of us are more familiar with on a hand's-on basis). 

With wing-mounted guns the bullets behave the same as rifle bullets, but the end result is massively altered by the pilot's LoS compared to the rifle shooter's LoS.  With a rifle, the LoS is only an inch or two from the level of the barrel.  With wing-mounted guns, the LoS is MUCH higher; nearly 60" above the barrels in a plane like the F4U.

With a rifle sighted in a 300 yards, the bullets will be hitting 3ft or so LOW at 600 yards (just a rough estimate, I haven't consuled my charts recently). 

With wing mounted guns in an F4U sighted in at 300 (300 yard convergence), the bullets will be striking 4-5' HIGH at 600 yards.


A 300 yard zero at 600 yards is giving you a 20' x 40' pattern with 6 guns. I'm not seeing an advantage in setting convergence to try to improve lead angles.
Title: Re: Convergence
Post by: mtnman on May 18, 2014, 01:32:56 PM
A 300 yard zero at 600 yards is giving you a 20' x 40' pattern with 6 guns. I'm not seeing an advantage in setting convergence to try to improve lead angles.

Exactly.  There's no lead angle advantage to gain with adjusting your convergence.

However, that wasn't what I was pointing to with my post.

Title: Re: Convergence
Post by: FLS on May 18, 2014, 02:30:41 PM
Exactly.  There's no lead angle advantage to gain with adjusting your convergence.

However, that wasn't what I was pointing to with my post.



The context was reducing required lead. You quoted my comment as if you disagreed. 
That can confuse people.   :D
Title: Re: Convergence
Post by: bustr on May 18, 2014, 06:28:13 PM
P51D

1. - Offline in TA map feild A1, parked at end of the runway facing north.
2. - Main gear just down the north cliff slope to raize the tail, datum line (CL) at 0 azimuth.
3. - Engine off.
4. - Convergence, all guns tested at 300 and 600.

Factory harmonization for the P51D was 300yds with the K14 set to "High Postition". The K14 had a sight high and sight low alignment setting. The gun convergences were 250, 300, 350. This was to achieve a maximum saturation pattern inside the maximum effective combat range for the AN\M2, and air combat effective range . The maximum effective range for the AN\M2 fired from a fighter at other moving aircraft was 1200ft(400yds).

A point about the offline target.

If you bring the target up with no azimuth setting, it will sit leveled to the datum line of your aircraft regardless of the datum lines AoA. Then if you fly on auto pilot at a speed which sets the AoA so that the datum line is level with the ground. You can draw an invisible line through your aircraft's datum line and the red horizontal line on the target.

Instead, it's easier to park your aircraft with it's wheels slightly downslope on a cliff off the end of a runway to level the datum line to the target's red horizontal line. Now you have a "bore sighting" stand. And if you have a Mil calibrated bore sighting gunsight like I do. You can create the charts below.

P51D 300yd & 600yd Convergence

CL - Target's Red Horizontal Line\Aircraft's datum line.
K14 - Center of the gunsight.
Gun - Impact center point of all gun patterns at range.
+ = Above
- = Below

300yd Convergence
Range-----K14 vs CL-----Guns vs K14-----Guns vs CL
100------(+19.8in)-------(-25.2in)-------(+9.0in)
200------(+10.8in)-------(-14.4in)-------(-7.2in)
300-------(00.0in)--------(00.0in)-------(00.0in)
400-------(-7.2in)--------(00.0in)-------(-7.2in)
500-------(-9.0in)--------(-9.0in)------(-18.0in)
600------(-21.6in)-------(-21.6in)------(-43.2in)

600yd Convergence
Range-----K14 vs CL-----Guns vs K14-----Guns vs CL
100------(-10.8in)-------(-25.7in)------(-39.6in)
200------(-50.4in)-------(-10.8in)------(-61.2in)
300-----(-102.6in)--------(00.0in)-----(-102.6in)
400-----(-129.6in)--------(00.0in)-----(-129.6in)
500-----(-189.0in)--------(00.0in)-----(-189.0in)
600-----(-205.2in)--------(00.0in)-----(-205.2in)
Title: Re: Convergence
Post by: bustr on May 19, 2014, 12:36:36 AM
Here's some F4u-1A hardstand bore sight fun. Yes and in WW2 nomenclature MntMan, it was called bore sighting when the plane was jacked up on a hardstand. Harmonizing was the process of bringing the guns vertical and horizontal convergence together with the gunsight line of sight to form a shot pattern at a set range with the gunsight line passing through the center.

F4u-1A

300yd Convergence
Range-----Mk8 vs CL-----Guns vs Mk8-----Guns vs CL
100------(-5.4in)-------(-36.0in)-------(-41.4in)
200-----(-50.4in)-------(-14.4in)-------(-64.8in)
300----(-102.6in)--------(00.0in)------(-102.6in)
400----(-144.0in)-------(+21.6in)------(-122.4in)
500----(-198.0in)-------(+36.0in)------(-162.0in)
600----(-237.6in)-------(+32.4in)------(-205.2in)
Title: Re: Convergence
Post by: mtnman on May 21, 2014, 11:12:22 AM
The context was reducing required lead. You quoted my comment as if you disagreed.  
That can confuse people.   :D


I was only referring to your comment about the rounds coming above the LoS.  Your statement that they don't come above that line enough to make a difference is incorrect depending upon the gun platform and the chosen convergence setting. They can come WELL above that line.

When it comes to assisting with lead you're correct, it isn't going to be helpful, and even if it was it would be a net loss of effectiveness once you factored in the horizontal aspects of the bullet grouping...
Title: Re: Convergence
Post by: TonyJoey on May 21, 2014, 11:22:18 AM
This "technique" doesn't work as you suggest; at least not on wing mounted guns (including the 50's).

Setting your convergence for 500 yards doesn't "get the guns pointed up a little bit"; it actually gets the guns pointed DOWN a little bit, so works contrary to your stated intent.

To point your guns up a little, it's necessary to bring your convergence point IN.




I'm thinking the guns would have to be pointed up a little bit to all converge at 500 yards, so that shots at 200 or 300 are on a higher part of the bullet arc.
Title: Re: Convergence
Post by: bustr on May 21, 2014, 12:10:04 PM
The default convergence for wing mounted guns in our game is the closest to real life for the horizontal ballistics.

Problem is, such as with American rides, the gunsight LoS should be left the same in most cases while only the horizontal converging point changed. The P51D is a good example. The K14 had two elevation settings. High and Low. These were for the expected role of fighter or fighter bomber, not if you wanted to furball at 400 and closer or pick from 600 and farther out. The relationship of the ballistic arch for the 50 cals stayed pretty much constant with the horizontal convergence being altered.

Our FW-A series is a good example. The default horizontal ballistic arch relationship to the Revi LoS is very close to real life. The horizontal convergence isn't. The wing root 20mm are 325 too short, while the outboard 20mm are 100 too short. And if you pull them out to match the harmonization chart for the FW-A series, you lower the bore angle of the cannons as you pull the horizontal convergence out to 400 and 600.

A lot of misunderstanding about the convergence settings by our player community, has created some interesting urban mythology about gunnery in the game.

You gents really should hardstand your fighters off the edge of some of the cliffs offline and actually look at the relationship at datum line 0 azimuth and your ballistic arch\LoS, and IP on the target at range. How many of you expected to see with the P51D at 300conv the 600yd drop was -43.2in versus 600conv the drop at 600 was -205.2in?

In real life the datum line azimuth was adjusted slightly nose down to harmonize the guns for the average expected combat speed at 15,000ft. Or some variation on this.

 
Title: Re: Convergence
Post by: mtnman on May 21, 2014, 12:23:18 PM
I'm thinking the guns would have to be pointed up a little bit to all converge at 500 yards, so that shots at 200 or 300 are on a higher part of the bullet arc.

While that is the common assumption (and is true for hand/shoulder aimed/fired weapons) that is untrue of wing-mounted guns.

The opposite is in reality true; the guns need to be pointed higher to converge at 200 (or 300) yards, and pointed lower to converge at 500 yards.

And once again, this is true for wing-mounted guns, but nose- mounted guns will follow suit much more closely with what we think of as "normal" due to our familiarity with pistols, rifles, shotguns, etc., which all have the barrel aligned much closer to the LoS.

This is due to the fact that the LoS is only an inch or two above the barrel with conventional firearms, and 50-60 inches above the barrel with wing-mounted guns.

I pointed this out with a bunch of screen shots in a thread a few years ago, but don't have time to do a search right now. The info is here on the BBS if you care to do a search though...
Title: Re: Convergence
Post by: bustr on May 21, 2014, 02:57:47 PM
I'm not sure how close to real gun and gunsight harmonizing our hanger app is. Since in many cases the gunsight LoS and the effective bore angle are lowered as we choose longer range horizontal convergence.

Basic wing gun harmonizing was for achieving the greatest amount of visibility over the nose of the fighter through the gunsight. This was limited by the maximum allowable elevation adjustment of the mounting cradles for the wing guns. Real world gunsights didn't have a Page_Up button that could move the reticle up to the top of the reflector plate to let you look over the nose while not changing the effective bore angle of the guns at the same time. Raising the gun elevation to max accomplished a clear LoS to the maximum combat effective range of the guns which was about 1200ft while allowing LoS to 2000ft. Then "harmonizing" the gunsight LoS to the bullet trajectory and maximum combat effective range 1200ft.

The next step was creating area patterns at the effective range to maximize the effect of the shot pattern. Opposed to shooting a rifle where you want to minimize your shot pattern at range as small as possible. This is where horizontal convergence comes in and minor variations in the effective bore angle. The secondary purpose for raising the guns elevation as high as possible, was that the gunsight LoS became effective for aiming the guns to 2000ft if the pilot needed to shoot that far. Horizontal convergence was to create a high probability hit zone at a "known range" to which the pilot aimed by pointing the pipper at the con and allowing for lead in Mils. It was only at longer distance, if at all, any bullet drop compensation in Mils was needed. Pilots had to be able to quickly rough estimate divisions of their main ring in terms of Mils. At least we don't get washed out of the game for failing gunnery ground school tests over Mil calculations with a 101Mil ring at range.   
Title: Re: Convergence
Post by: TonyJoey on May 21, 2014, 07:41:40 PM
While that is the common assumption (and is true for hand/shoulder aimed/fired weapons) that is untrue of wing-mounted guns.

The opposite is in reality true; the guns need to be pointed higher to converge at 200 (or 300) yards, and pointed lower to converge at 500 yards.

And once again, this is true for wing-mounted guns, but nose- mounted guns will follow suit much more closely with what we think of as "normal" due to our familiarity with pistols, rifles, shotguns, etc., which all have the barrel aligned much closer to the LoS.

This is due to the fact that the LoS is only an inch or two above the barrel with conventional firearms, and 50-60 inches above the barrel with wing-mounted guns.

I pointed this out with a bunch of screen shots in a thread a few years ago, but don't have time to do a search right now. The info is here on the BBS if you care to do a search though...

I thought about exactly what you said after I had posted and left this morning. You are 100% correct, as the LOS is the key difference and the err in my thinking. Thank you.  :aok
Title: Re: Convergence
Post by: mtnman on May 25, 2014, 09:26:13 PM
I pointed this out with a bunch of screen shots in a thread a few years ago, but don't have time to do a search right now. The info is here on the BBS if you care to do a search though...

Here's the link to the thread which has screenshots of the effects of various convergence settings.

http://bbs.hitechcreations.com/smf/index.php/topic,291146.0.html

Once you understand how the arc of the bullet is effected by altering your convergence, you'll actually note that the bottom image in the convergence picture posted by ImaDot is actually kind of misleading, and potentially inaccurate...
Title: Re: Convergence
Post by: FLS on May 25, 2014, 09:37:02 PM
That's a nice well illustrated lesson Mtnman.  :aok
Title: Re: Convergence
Post by: Naughty on May 25, 2014, 10:55:07 PM
deleted,  my bad
Title: Re: Convergence
Post by: Kingpin on May 26, 2014, 12:11:53 AM
That's a nice well illustrated lesson Mtnman.  :aok


Wish I had found that thread a year ago.  I did all that testing and offline shooting at the target myself for the VF-17 gunnery course.  Good to see it coincides exactly with my results and information. In fact, discussing convergence and the bullet stream, exactly as covered in those screen shots, is about the first half-hour of my gunnery course!  

It's also one of the reasons I use the Corsair for the course, as its ballistics are a little more quirky compared to other 50-cal packages; the greater vertical separation between the gun-bore and the LOS has a more dramatic effect on the ballistic arc inside and beyond convergence in the Hog, as compared to the Pony or Jug 50-cals.

Good stuff.

<S>
Ryno
Title: Re: Convergence
Post by: bustr on May 27, 2014, 04:51:25 PM
Here's the link to the thread which has screenshots of the effects of various convergence settings.

http://bbs.hitechcreations.com/smf/index.php/topic,291146.0.html

Once you understand how the arc of the bullet is effected by altering your convergence, you'll actually note that the bottom image in the convergence picture posted by ImaDot is actually kind of misleading, and potentially inaccurate...

If you hardstand with the main gear slightly down a cliff face to make the datum line 0 azimuth or somewhere inside of 17.8Mil nose low of the datum line to reproduce AoA at 15,000 at combat speed. The datum line is the horizontal red line on the target equal to "0" degree when you don't use azimuth in the target command. You will get a very different out come for the F4u. I posted that earlier with the convergence of all guns set to 300. During auto level flight testing, you slow the fighter down with long firing bursts while trying to create good looking dispersion blobs for screen shots. Gets even worse 20k and above trying to test for max range.

Hard standing the fighter with the engine off, you can blaze away until the cows come home and not change the AoA. It takes a bit of practice easing the main gear down a cliff face, head down in the cockpit zoomed in on the artificial horizon first, trying to set it level. Then the second place to check is from F3 using Numpad_2 with the target set between 3-4yds so your spinner or prop hub just pokes through.

One degree in terms of the prop hub doesn't look like much. At 17.8Mil, at your convergence point say 300yds. About 160ft of missing from your bore line if it were a laser cannon. But, since your gunsight and ballistic arch is harmonized, you are aiming about 6 standard Mk8 (3Mil) center dots high at 300yards. Hitech has programed your nose noticeably raising from sustained firing of wing guns. I've seen 5Mil, while sustained fire will slow your plane down in auto level raising the nose even more.

I wish listed once for a hardstand gunnery testing app or location a long time ago. 

Title: Re: Convergence
Post by: Schatzi on May 27, 2014, 05:56:52 PM
http://slowcats.de/slowcats1/AHTC/Convergence.pdf
Title: Re: Convergence
Post by: Lusche on May 27, 2014, 05:57:35 PM
Look who's there...  :old:  :rock
Title: Re: Convergence
Post by: Schatzi on May 27, 2014, 06:11:37 PM
Im kinda all theory and no go.... not sure id even get my Hurr off the ground. Damn work leaves me no time to play. But I just dropped by and couldnt let that convergence discussion leave be... flying a Mk1 it was kind of a main thing.... try shoot something with a Mk1 set to 400 ^^

PS: Where the heck did my Casper go ?
Title: Re: Convergence
Post by: FLS on May 27, 2014, 06:42:19 PM
Schatzi!    :D
Title: Re: Convergence
Post by: mtnman on May 28, 2014, 10:28:24 PM
If you hardstand with the main gear slightly down a cliff face to make the datum line 0 azimuth or somewhere inside of 17.8Mil nose low of the datum line to reproduce AoA at 15,000 at combat speed. The datum line is the horizontal red line on the target equal to "0" degree when you don't use azimuth in the target command. You will get a very different out come for the F4u. I posted that earlier with the convergence of all guns set to 300. During auto level flight testing, you slow the fighter down with long firing bursts while trying to create good looking dispersion blobs for screen shots. Gets even worse 20k and above trying to test for max range.


That's not the method I use for my testing, and I don't experience the issues you mention.

First of all, I'm not really interested in the AoA at various speeds, because what I'm testing is the effect of various convergence settings at various ranges.  Tossing varying AoA into the picture just adds another variable, and added confusion.

Second, since (while fighting) I'm generally not limiting myself to firing at certain speeds, or at dead-level flight attitude, I don't see any value in working to match specific AoA or speeds.  IMO, there's more value in learning what the bullets are doing in as static an environment as possible.

To do that, I think the greatest value can be drawn from the testing only if the pipper is sitting dead-center in the dot-target.  That's easy to achieve in auto-level, by adjusting the throttle to control AoA, and giving the plane time to stabilize at whatever speed puts that pipper (and allows it to stay) dead-center in the target.  I use lots of zoom to verify that.  I don't really care if the plane is flying at X, y, or z AoA, as long as the pipper remains centered on the target.

Next, there's no sustained firing involved in my testing, so I don't have the slowing-effect of firing the guns to worry about.  Once again, that's just extra variables thrown in to confuse the results...  Instead, I fire in MANY short bursts, giving time between bursts to ensure I'm staying at a stable speed, and my pipper is remaining locked on the target center.  My method is more like firing multiple shots from a bench-rested rifle on the range to achieve tight groups.  The only difference is that in my "single-shot" world in the fighter a small sprinkle of bullets goes downrange, rather than one bullet at a time.  The groups you see in my screenshots may each have been a result of 20 or more extremely brief trigger-squeezes, all aimed at the same spot, and fired at the same speed.

A hardstand would be nice (but of extremely limited value to players) and I think the whole cliff thing is a lot more effort than is required to learn what this type of experiment has to teach.

(http://i107.photobucket.com/albums/m309/Mtnman_03/boresite.jpg) (http://s107.photobucket.com/user/Mtnman_03/media/boresite.jpg.html)

I think that beyond the straight/level testing, it's good to know how various attitudes of flight will effect the trajectory of rounds fired, but it's exceedingly difficult to see those in controlled experiments in-game because the lack of autopilot adds so many variable to the puzzle as to hopelessly confuse the results (for most pilots at least).  While it's important to know how bullet trajectory "behaves" in the near-perfect straight and level world, it's also important to know how things change when we fire in combat.

This chart is a pretty good representation of how banking affects things:

(http://i107.photobucket.com/albums/m309/Mtnman_03/Copyofp-51b-guns.jpg) (http://s107.photobucket.com/user/Mtnman_03/media/Copyofp-51b-guns.jpg.html)
(http://i107.photobucket.com/albums/m309/Mtnman_03/untitled8.jpg) (http://s107.photobucket.com/user/Mtnman_03/media/untitled8.jpg.html)

And once you point your nose up a few degrees, you start affecting the shape of the trajectory as well; once you're firing vertically, there's essentially no trajectory at all (the bullets just go straight up, and then fall straight back down, if we don't have wind or rotational drift modeled).  Bullets fired horizontally will display a more curved trajectory (within working ranges), while bullets fired upwards (or downwards) will fly a "flatter", less-curved path (within working ranges).

(http://i107.photobucket.com/albums/m309/Mtnman_03/cannon2.jpg) (http://s107.photobucket.com/user/Mtnman_03/media/cannon2.jpg.html)

However, if we fire straight up in the game, our guns are actually aimed beyond vertical, and that has an affect as well...  The bullets will cross the line of sight sooner, and will never fall back through it...

(http://i107.photobucket.com/albums/m309/Mtnman_03/Firingstraightup.jpg) (http://s107.photobucket.com/user/Mtnman_03/media/Firingstraightup.jpg.html)

Firing straight down (or even upside down) will give similar (but not identical) results (as seen from the pilot's seat).

(http://i107.photobucket.com/albums/m309/Mtnman_03/Firingstraightdown.jpg) (http://s107.photobucket.com/user/Mtnman_03/media/Firingstraightdown.jpg.html)
(http://i107.photobucket.com/albums/m309/Mtnman_03/MGonlyInverted.jpg) (http://s107.photobucket.com/user/Mtnman_03/media/MGonlyInverted.jpg.html)

Title: Re: Convergence
Post by: bustr on May 29, 2014, 05:49:49 PM


A hardstand would be nice (but of extremely limited value to players) and I think the whole cliff thing is a lot more effort than is required to learn what this type of experiment has to teach.


And I don't have such a low opinion of what "players" should be limited to knowing for their own good. They are all paying the same $14.95 I am.
Title: Re: Convergence
Post by: FLS on May 29, 2014, 06:00:24 PM
And I don't have such a low opinion of what "players" should be limited to knowing for their own good. They are all paying the same $14.95 I am.
You completely misstated what Mtnman said. He never said they shouldn't know. He just pointed out the likely benefit of knowing. You tend to lose rationality at any hint of disagreement.  Calming down might increase your comprehension.
Title: Re: Convergence
Post by: mtnman on May 29, 2014, 10:32:21 PM
And I don't have such a low opinion of what "players" should be limited to knowing for their own good. They are all paying the same $14.95 I am.

Are you inferring that I think players should be limited in what they're allowed to know?  Seriously?

Having a bad day?

Do I really need to go into detail about why i think the value of modeling a hardstand would be of limited value?  Really?