Hi,
just wanted to offer some informations about how the bullet flight path, the convergence, the muzzle velocity etc are programmed in EAW and something about the related problems while making damage models and playing the game.
Ok, 1st how its programmed:
The gravity effect on the bullets is calculated correct, unfortunatelly bullet velocity dont reduce with the flight time(probably to safe calculation power).
The Rate of fire got reduced to 50% of the real RoF(probably to safe calculation power).
The target hitbubbls are just round. We have two per wing, Tail, Fuselage front, Fuselage center, Pilot.
In EAW1.2 we have just a dispersion for each gun, but no guns convergence.
In EAW1.28x we did dissable the dispersion on fighter guns, in favour to an Guns convergence(adjustable in x and z direction).
Now the resulting problems:
The missing bullet drag influence(reducing bullet speed) can cause different problems.
If we set the Bullet velocity = real Muzzlvelocity, the bullets dont fall down like they should and the time to target is so smal, the guns work almost like Laser guns.
If we take a MG151/20 with 800m/sec Muzzlvelocity, the bullet need just 0,5 sec to 400m and only 0,25 sec to 200m.
In real life the speed of the Bullets initially reduce extreme, on around 200m we have just around 60% Muzzle velocity, on 500m its less than 40%.
So on 400m distance the Bullets need around 1 second, not just 0,5 seconds.
Since the gravity calculation in EAW is correct, the bullets wouldnt have the correct time to fall down, so the flight path would we way to flat.
Here the flight path datas of the inner wing MG151/20 of the FW190A6 as example:
The Gun is located 1,1m below the Sightline, so it need to shoot upward to cross it.
After 125m the bullets cross the sightline.
After 350m the Bullets reach a highest point of 84cm over the sightline.
After 550m the Bullets cross the sightline again.
After 620m the Bullets are down to 1,1m below the sightline again.
So within 620m the bullets fly almost 2m upand downward.
Since even fuselage of a B17 is not 2m high, not to talk about a fighter, we have a rather smal space where we can hit a target by aiming right onto it.
With a constand Muzzlevelocity and so only 50% time, the flight path would be half as high and, what is most important, always within the size of a normal target.
Now we could say we just use 50% Muzzle velocity, but then the Bullets would be way to slow on short distance(30-200m).
So in EAW1.2 they did use around 83% MuzzVel and in EAW1.28e we use between 75 and 83%, depending to the guns.
This of course still lead to a much to flat flight path.
This flat flightpath and the to high bullet speed on long range is the reason why its rather easy to hit on very long distances(600m +), compared to real life, where such distances needed pure luck.(in EAW1.2 this was way more easy, cause the guns dont had convergence)
On the other hand, in EAW , wing mounted guns have much trouble to hit at short range, cause the bullets reach the sightline in around 250m distance, if we reduce this they would go 2 meters above it. So in 50m distance the bullets are still around 80cm below the sight line, so you have to aim way above the target to hit in such distances.
The reduced RoF of course cause to many space between each bullet, specialy while shooting with deflection this give unrealistic results, specialy when the planes have a smal number of guns.
For example the 8 brownings of the Spit1a or Hurri dont leave any space at all, but with the two 20mm´s of the Bf109E its pure luck to hit while shooting with deflection.
Here some calculations:
8 x Browning .30cal with a RoF of 20 Rounds per sec and a Muzzle Velocity of around 750m/sec.
So per gun there are 20 rounds in the Air on a distance of 750m. Since the guns always shoot in pairs, we have 4 shoot secquences.
So there are 80 Bullet pairs on 750m distance, so the distance between each bullet pair is 9,3m.
Since we fire with 50% RoF, our Spit/Hurri Bullets have a space of around 18,5m.
While shooting with a normal deflection of max 25 degrees, the target cant fly through this space without to take hits.
Same with the MGFF 20mm of the Bf109E:
2 x MGFF 20mm with a RoF of 8 Rounds per sec and a Muzzle Velocity of around 585m/sec.
So per gun group (we have just one)there are 8 bullet pairs in the Air on a distance of 585m, so the distance between each bullet pair is 73m in real life and in EAW we have 146m.
While with 73m and shooting with a normal deflection of max 25 degrees, the probability that the target fly through this space without to take hits is rather smal, with 146m this probability increase extreme.
With slow shooting Guns with higher Mizzle velocity its even worse.
The limited number of hitbubbles and their round form are another bad thing.
If we adjust the hitbubbles to fit to the wing height, we will have trouble to hit the wings while deflection shots. So we have to adjust them in a compromise.
In EAW1.2 the hitbubbles are around 8 times as big as the plane. In EAW1.28e the wing hitbubbles cover almost the wing span, only the wingtips are not covered. The Fuselage bubbles cover the fuselage from the rear, so between front bubble, center and rear bubble is a little space(not a problem).
So if you attack a plane strait from the rear, the wings are a to big target, with deflection the wings are to smal, but all over imho this is realy a good adjustment.
Dispersion vs Guns Convergence:
Long time ago(long before we had the code) i found out that the guns dispersion work more like a bullet hitbubble size.
Instead of reducing the hitprobability it got increased by increasing the dispersion.
This was so, cause the influence of the mistakes above(to big hitbubbles, to High Bullet Velocity).
When we got the code one of the 1st things we did was to work out a guns convergence. To be able to do this we needed some values in the already existing external files, to adjust the convergence for each gun. So we took the dispersion values, dissabled the dispersion in favour to the guns convergence.
The result was/is very good, cause without guns convergence wingmounted guns never could show their full potential on perfect shooting distance(around 250m), on the other hand on very long range the buttlets still did fly toward the target(rather easy long distance kills).
Ok, The last days i was working on the code again and i managed to introduce a bullet drag, so that the bullet speed reduce with the speed, resulting in a very realistic bullet flight path.
With this we can adjust the guns way more easy(realistic MuzzVel) and realistic.
Unfortunatelly it will last some more time until i did readjust all the planes to fit to this, but i can tell you, the result is great!!
On short distance its now way more easy to get a kill and on +600m it will be pure luck.
Greetings,
Knegel
