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249th_Harrier
07-28-2004, 06:13 AM
I believe that the inaccuracy of rockets needs to be modelled in the game. In AEP rockets are by far the most effective anti-armor weapon. This just does not match the historical record. For example I have included a quote from this link:

http://www.usaaf.net/ww2/dday/ddpg8.htm

/quote
While acknowledging the spectacular effects and destructiveness of rockets, the AAF considered bombs more effective for "road work" due to accuracy problems in firing the solid-fuel weapons.
The British, on the other hand, preferred rockets, the Typhoon carrying eight having 60-lb armor-piercing warheads. Possibly this difference of opinion stemmed from launching methods; the P47s used "zero length" launchers while the Typhoons used launch rails. It could be expected that the rails would impart greater accuracy, stabilizing the rocket immediately after ignition until it had picked up sufficient speed for its tail fins to stabilize it. (There is, however, an interesting report from Montgomery's 21st Army Group that questions the alleged success that British air-to-ground rockets enjoyed against tanks and motorized transport.)
quote/

249th_Harrier
07-28-2004, 06:13 AM
I believe that the inaccuracy of rockets needs to be modelled in the game. In AEP rockets are by far the most effective anti-armor weapon. This just does not match the historical record. For example I have included a quote from this link:

http://www.usaaf.net/ww2/dday/ddpg8.htm

/quote
While acknowledging the spectacular effects and destructiveness of rockets, the AAF considered bombs more effective for "road work" due to accuracy problems in firing the solid-fuel weapons.
The British, on the other hand, preferred rockets, the Typhoon carrying eight having 60-lb armor-piercing warheads. Possibly this difference of opinion stemmed from launching methods; the P47s used "zero length" launchers while the Typhoons used launch rails. It could be expected that the rails would impart greater accuracy, stabilizing the rocket immediately after ignition until it had picked up sufficient speed for its tail fins to stabilize it. (There is, however, an interesting report from Montgomery's 21st Army Group that questions the alleged success that British air-to-ground rockets enjoyed against tanks and motorized transport.)
quote/

jurinko
07-28-2004, 07:02 AM
I agree. BRS rockets were used aginst concentrations of vehicles because it was impossible to hit single target due to their unexpectable trajectory.

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Letka_13/Liptow @ HL

Willey
07-28-2004, 07:58 AM
It's modelled (I'd rather say overmodelled, because it's too much spread) already for the R4Ms...

LeadSpitter_
07-28-2004, 12:15 PM
definatly, and not make us have to get 2 with direct convergence to kill a tank online.

you can hit a tank 6 times online hitting it with 1 rocket each time and it wont be destroyed. But you hit it once with direct convergence and its destroyed. Same thing with bombs online. 2x1000lbers can just miss a tank. having the blast crators under the tank its its fine. We need to get it directly in the center to destroy a tank.

Kinda makes no sense in having 1000lb 500lb 250lb 1 direct hit 1 tank kill

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Fillmore
07-28-2004, 12:41 PM
People bring this up a lot. When they do I feel obligated to bring up that bombs are far more affected by lack of random dispersion that rockets. Drop bombs from 7000m with pinpoint accuracy, no dispersion no nothing, is more overmodelled than having rockets travel a few hundred meters without such effects.

I also think alot of the uber accuracy we see in game is from how close we are when we launch them. How many countless times have we crashed into the ground practicing our tequeniques? Real pilots had no such opportunity and had to launch from a distance where they were safe from crashing and did not have the luxury to simply not fire and come back around for another pass if their first pass wasn't perfectly set up.

If rockets were modelled with more random dispersion then people would simply get even closer before firing them and they would still be uber accurate with them compared to what real pilots were.

I think if real pilots had been as suicidally inclined as us they would have just as good a hit rate with their rockets, and if they had had the opportunity to die dozens of times practicing they would get so good that they could do it without fear of dieing.

Other factors like wind and wing flex or whatever may not be possible with the game engine. I believe Oleg has already stated that the rockets are modelled with correct ballistics (ballistics inherent to the rocket itself I assume and not environmental factors).

p1ngu666
07-28-2004, 02:07 PM
the worst is aa and other guns that are just static. there a small target so hard to hit, and a DIRECT is often needed to kill them
ive had rocket blasts like 30cm away to each side and gun is firing away still (and gets my cables, ofcouse)
at that close range, i would have maimed the crew horribly, minium, hence deactiviating the gun

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249th_Harrier
07-28-2004, 02:19 PM
Fillmore, I respectfully disagree. Rockets in AEP launch absolutely straight, and fly absolutely straight. The result is that the effectiveness of ground attack weapons is heavily skewed toward rockets in the game, something which is not in agreement with historical fact. As my reference indicates, rockets were mostly ineffective against armored targets. This was due to insufficient accuracy. High velocity KE weapons with tungsten ammunition, on the other hand, WERE effective, and used by Rudel et al. The inaccurate modeling of rocket ballistics makes a rocket-armed I-153 a more potent anti-armor weapon than the Rudel's stuka-G, which clearly was not the case in RL.

RAF74_Buzzsaw
07-28-2004, 02:33 PM
Salute

Agree, rockets are far too accurate. A 1000 lb bomb was much more likely to be able to kill a tank. In fact even a near miss will kill one. I have read descriptions of French tanks in 1940 under attack by Stukas armed with 550 kg bombs, and the tanks were actually tossed in the air by the explosion.

Fillmore
07-29-2004, 09:45 AM
"Rockets in AEP launch absolutely straight, and fly absolutely straight."

Yes, I know. I know they shouldn't. What I am saying is that I don't think it has to do with the rockets' ballistics being modelled incorrectly per se. Same with bombs, they drop 7000m exactly the same every time with no variance, and they shouldn't. That they launch straight is not a property of the rocket, it is a property of the launching platform. In the .50 cal dispersion thread (the original one I think) Butch2k mentioned that this was also a problem with bullet dispersion, all were too precise because vibration of the plane was not modelled. Same with rockets, same with bombs. No atmospheric effects either. And even if you modelled all that we in game would be far more accurate with them than real pilots were. This makes the difference seem less than irl (if you halve two numbers you halve the difference, becoming more accurate than normal real pilots with an already accurate weapon is less noticeable than becoming more accurate with an innaccurate weapon).

The one thing that might be able to be done is to have some random variation in the rocket motor performance, rather than model every rocket of a given type as being absolutely identical in this regard, each rocket would still fly straight (I think without any environmental factors or manufacture defects rockets do fly straight), but with slightly different speeds/trajectories.

Yes it would be nice to have wind affect the rockets' flight, and it would be nice to have the vibration of the aircraft affect the launch etc., but I think if the game engine could do that it would already be done.

It may seem like just semantics, but Oleg is an engineer and he seems to me rather picky about thses sorts of things (like if you tell him muzzle flash is too big, he will say no, size is correct. Well, he is right, it is just that when we say they shouldn't be so big we mean more than just size). To say that rocket ballistics should be modelled differently, or that they shouldn't be so accurate, is different than saying their accuracy should be affected by things that aren't modelled.

perioikos
07-29-2004, 11:05 AM
This was a major discussion quite a while back. According to Oleg, the attested inaccuracy of the rockets was due to mishandling of the rockets by the groundscrew (attributed to bent stabilizer fins), which was corrected early on by proper packing during shipment, and handling techniques; this of course addresses only the russian rockets.

Rockets do seem simplified, both in ballistics and damage, but this'll have to be lived with. As a general comment, from lack of aircraft vibration, complex weather, to mechanical failure et al., things feel a little too clean and perfect ... without the random chance, the whole misses a little on the art-side of the experience.

249th_Harrier
07-30-2004, 04:11 PM
I have been looking for rocket guncam footage to get a better idea of the character of 40's era rocket ballistics but no luck yet. Anyone who has flown model rockets (similar to 40's rockets I think) knows that 1) Launch angle can be variable, esp if not stabilized with guide during launching phase 2) Sometimes they veer to one side or another due to imperfect aerodynamics 3) Sometimes they oscillate due to knuckleball-type effects, resulting in an s-shaped trajectory.

I assume item 1) could be adequately modeled using the current game engine, using the same dispersion algorithm as the notorious 50 cal bullets. Item 2) would take extra coding, the rocket whould need to have a randomized yaw force applied to affect the trajectory. Item 3) would take even more coding but would look darn cool http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif. I think the immersiveness and historical accuracy of ground-attack in the game would be improved with realistic rocket ballistics.

Vipez-
07-30-2004, 05:15 PM
Yup, reading memoirs by Finnish JU-88 pilots.. when they dropped 1000 kg bombs to Russian T-34s, the pilot descriped the tank actually could flew 100 meters away by the shoch wave alone..

About the rockets, I definately agree.. though the german rockets seem to be realisticly unaccurate, but US and most of all VVS rockets allways have been one hit one kill- Sidewinders.. been like so since the first IL-2.. I'm not sure what would be the proper way to model it.. In real life even the Sturmoviks fired their rockets in salvos. Maybe firing rockets automaticly in salvos would be the solution to add more realism.. http://ubbxforums.ubi.com/images/smiley/16x16_smiley-indifferent.gif


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249th_Harrier
07-30-2004, 10:38 PM
I still have not been able to find any guncam footage, but I found an interesting quote in a discussion group by John Phillips, co-author of Flying Guns: World War II:

QUOTE
"The ineffectiveness of [RAF+USAF] air attack against tanks should
have caused no surprise because the weapons available to the
fighter-bombers were not suitable for destroying them. Put simply, the
heavy machine guns and 20 mm cannon were capable of hitting the tanks
easily enough, but insufficiently powerful to damage them, except
occasionally by chance. The RPs and bombs used were certainly capable
of destroying the tanks but were too inaccurate to hit them, except
occasionally by chance."

However, the Allied fighter-bombers were far more effective in
destroying the unarmoured support vehicles, such as fuel tankers, on
which the Panzers depended to make progress. Their attacks also scared
the pants off many less experienced tank crews, causing them to
abandon their vehicles, and could thus disrupt tank operations.

The German and Russian attack planes carried powerful, large-calibre
cannon firing armour-piercing projectiles. For information about these
guns and their effectiveness, see:
http://www.quarry.nildram.co.uk/tankbusters.htm

You need to take German and Russian claims for tanks knocked out from
the air with a pinch of salt, though. British Operational Research
teams which investigated the causes of tank losses concluded that the
claims of the fighter-bomber pilots were overstated by about ten
times.
UNQUOTE

249th_Harrier
07-30-2004, 10:55 PM
Here is another quote from Tony Williams:

QUOTE
"Even under practice conditions, the hit rate for the RPs against
tanks was no better than 5%. This was graphically illustrated by a
demonstration put on by Typhoons against a captured Panther tank
placed in the middle of an open field, helpfully painted white with
large red crosses on it to make sure the pilots could see it. Of the
64 RPs fired (launched in a typical steep dive at ranges of 750-900
m), only three hit the tank. In battle, RP accuracy was considerably
worse than this, with the official British calculation of hit
probability against a single tank being 0.5% (in other words, 200 RPs
had to be fired for each hit). Furthermore, some 20 ^ 30% of RP
warheads failed to explode."
UNQUOTE

Aaron_GT
07-31-2004, 01:42 AM
" (launched in a typical steep dive at ranges of 750-900
m), only three hit the tank."

It would be interesting to see what the hit rate in the game would be if we launched rockets at 750-900m. I would guess that most people in the game launch them at perhaps half that distance.

Fillmore
07-31-2004, 06:25 AM
Hehe, I was going to pull out the same part Aaron did. I have only used rockets on rare occasions. The first couple tries I missed, but then I developed the method of getting right in under 200m before firing, and from a shallow angle not steep dive (crash if that close in steep dive).

"Furthermore, some 20 ^ 30% of RP
warheads failed to explode"

And of course real rockets were not all identical clones of a perfect specimen. Same with bombs.

Aaron_GT
07-31-2004, 08:23 AM
200m - now that IS close!

I think there are two reasons why people in the game launch when close

1. No fear of dying
2. You can't really see the target very well on the standard FOV from 900m (a compromise due to current display technology).

It would be interesting to see how overmodelled kill rates are from 900m though. Like I said - unless zoomed in (the zoomed in FOV is actually 1:1 modelling of the outside world in the sense of angles subtended at the eye) you'd be hard pressed to see something at 900m in the game well enough to hit it.

Covino
07-31-2004, 02:17 PM
There another thing wrong with the rocket physics.

When a rocket is launched it shifts a lot to face the direction of the oncoming air or flight path (the direction of the plane is different than the flight path because of yaw and AoA). Therefore, the rocket flies in the direction of the planes flight path, not neccesarily the direction of the plane due to the airflow of the oncoming air at the point the rocket is launched. Warbirds simulates this well.

Pilots had to take care that their planes were flying smooth/straight on an accurate rocket attack because any kind of yaw or large AoA would send the rocket to the side or up/down of their crosshairs.

In IL-2 the rocket just go where you point them, no matter what the status of the plane. Anyone get what I'm saying? http://ubbxforums.ubi.com/images/smiley/354.gif

Aaron_GT
07-31-2004, 02:32 PM
"Therefore, the rocket flies in the direction of the planes flight path"

It won't do that. The path will be a sum of vectors based on the flight path and the attitude of the plane, but the rocket won't follow the flight path exactly if the plane is yawing.

Covino
08-01-2004, 08:55 AM
You are correct. That is why I said, "When a rocket is launched it shifts a lot to face..."

It doesn't chnage direction completely but it does have an effect.