DCS Bf 109K-4

Low mass? Not sure where that comes from.

 

Ok, it might not be "crazy," but that's a pretty big deceleration in the horizontal axis if it is true!:wassat:

More important than mass, to ballistics, is density. The 30mm minengeschoss is filled with low-density HE filler, and this means that its inertia-to-drag ratio is really, REALLY crap. It also isn't a particularly aerodynamic shape, as far as bullets go.

So you have a slow, draggy bullet with little inertia... that means it's going to lose velocity very quickly.

A quick tap-a-tap on a ballistic calculator (at http://www.jbmballistics.com) shows that, with the assumption that the shell has an initial velocity of 500 m/s and a ballistic coefficient (the drag-to-inertia ratio) of 0.3 (which is actually quite high; well-designed solid metal .30 caliber rifle bullets are generally in the 0.3-0.4 range, higher is better), the aircraft is at 5,000 feet, external temperature 50*F, and with gunsight mounted 36 inches above the guns, the shell does indeed drop 1317 inches/ 33.45 meters in the first 1,000 meters.

And all that is assuming a "zero" range of 100 meters, which means the cannon is aimed quite high, to loft the shell up into the 36-inches-high line of sight at 100 meters. If you set zero range to null (IE, the sight and guns are aimed parallel, rather than the guns aimed up to "meet" the higher line-of-sight from the cockpit gunsight), the drop becomes 1728 inches/ 43.89 meters. Lines up pretty close with his values for the bullet drop.

so that shows that the mk108 drops 3,4m within the first 400m.

 

but i guess it doesnt really matter...with training one will get used to its trajectory, and then it sure will be deadly.

No, it drops 4.6 meters... but since it's "lofted" up toward the line of sight, the displacement between line of sight and path of projectile is lessened.

If its velocity was only averaging 427m/s over 400m I'd hate to see what it drops to by the 1000m mark. I'm guessing this won't be a long range sniper weapon on B17s when they are released unless I'm using David as my spotter.

Ballistic calculator indicates that at 1000 meters, it only maintains 765 feet per second/ 233 m/s. Around 521 mph. Not a lot faster than the airplane at which it is shooting! Mighty, mighty slow.

As comparison, the .50 caliber maintains 1941 fps/ 591 mps / 1323 miles per hour at 1000 meters. And drops only 297 inches/ 7.54 meters below the line of sight (assuming the gun and sight are parallel, rather than zeroed, similar to where the 30mm dropped 1728 inches/ 43.89 meters). Given the flatter trajectory, it makes no sense to go for the 100 meter zero with a 36 inch offset on the .50: at that setting, the bullet comes up through the line of sight at 100 meters, and CONTINUES to rise above the line of sight, remaining a full 80 inches high at 1000 meters. However, with a 700 meter zero in those conditions, the trajectory is never more than 95 inches either high or low above the line of sight (21 inches above at 500 meters, 95 inches low at 1000 meters). A mere 2.41 meters of trajectory displacement to worry about.

I would also note that when you're firing at a maneuvering fighter (IE, turning, banked sideways), it further complicates matters, because the shell isn't going to drop "down" the gunsight, it's going to drop down toward Earth... which means you'd have to aim ahead of AND significantly above, with the 30mm. Certainly makes gunnery a challenge.

Now, this probably explains why, with the .50 in DCS, all I have to do when strafing is place the pipper on the target, with no height offset, and expect good hits at any halfway reasonable range (1km or less), while I can't strafe for beans with the 20mm, because it's trajectory is worse. ...and the 30mm will be even harder!

FW with mk108 gunpods vs B17

Just read one pilot account and hes said in the FW190A version they flew had 20 and 30s in the wing tips (13mm removed and armor plate inserted). When diving into the bomber formations they would fire the 20s at 400m and 30's at 200m.

The standard outer wing cannons on the A-8 (from A-6 onwards) were 20mm MG151/20. The /R2 and /R8 replaced them with 30mm MK108s.

The A-3 to A-5 had 20mm MG-FF cannons in the outer wings.

The A-2's inner wing weapons, 7.92mm MG17s, were replaced with MG151/20 20mm cannons.

 

FW with mk108 gunpods vs B17

This video get posted on every discussion about the 108, but it does show the destructive power quite well.

Wouldn't want to be the tailgunner.

Posted this before, but here's a Spitfire shot down with Mk 108:

Guys, plz can't wait... :sad_2: ^up you stimulate too much

This video get posted on every discussion about the 108, but it does show the destructive power quite well.

 

Wouldn't want to be the tailgunner.

 

Posted this before, but here's a Spitfire shot down with Mk 108:

 

Quite a recoil!

So... Will the 109 have any additional armament in the game?

Quite a recoil!

The nose definitely gets thrown around when firing, but seems like the vibrating camera exaggerates it.

So... Will the 109 have any additional armament in the game?

Hopefully the MG151 gunpods. If I remember correctly, it was an available field mod.

 

FW with mk108 gunpods vs B17

Incredible hitting power, but I wonder why that 109 wasn't ripped to shreds by the tailgunner. Not like he was doing any kind of defensive maneuvering... he just came in really steady and slow to firing position. Should have been easy pickings for the tail.

Incredible hitting power, but I wonder why that 109 wasn't ripped to shreds by the tailgunner. Not like he was doing any kind of defensive maneuvering... he just came in really steady and slow to firing position. Should have been easy pickings for the tail.

There many similar videos with no return fire from the bomber. As Sith said, gunner incapacitated, for if he wasn't the attacking a/c would have been ripped to shreds at that distance and no cine film would have existed.

the gunner was probably waiting for the FW to close in at <400m before he started firing and got killed in the first spraying round before he had a chance. (looks like the fw pilot started shooting at about 400m and used the rudder to disperse his shots)

Ok 4 days is long enuff!!!!

Where dafuq is my BF 109????

:)

I'm kidding.

ED don't hurt me.

considering we are supposed to get our hands on it this month, i assume an release date announcement is about to be made any day now.

considering we are supposed to get our hands on it this month, i assume an release date announcement is about to be made any day now.

Aaaaaaah! Takes too long!!!!:pain:

Incredible hitting power, but I wonder why that 109 wasn't ripped to shreds by the tailgunner. Not like he was doing any kind of defensive maneuvering... he just came in really steady and slow to firing position. Should have been easy pickings for the tail.

Well, not exactly.

1st - Imagine you are shooting an actual M2 .50 on the ground, trying to hit something at some hundreds of meters;

2nd - Have a light barrel on that HMG which will decrease your accuracy but lighten the recoil (I think?);

3rd - Get you and the gun in movement;

4th - Get your target also moving;

5th - Add thick glass just infront you;

6th - Add the turbulence factor;

7th - Add a general slight shaking everywhere (engines, uneven air, etc.);

8th - Remember you are instructed to only shoot small bursts of 10-15 rounds per gun and have a certain cooldown time (it's stated in various manuals of the time, I'll try to find them);

9th - Even if one bullet hits, it's possible it wouldn't do that much damage, they are just HMG bullets after all, not cannons;

10th - Maybe more stuff I missed?

If it was that easy, they wouldn't really need escorts. :thumbup:

Also, think about how much smaller the target plane is, coming almost straight from behind.

considering we are supposed to get our hands on it this month, i assume an release date announcement is about to be made any day now.

Well... there are 30 days in November... 26 now :)

Well... there are 30 days in November... 26 now

shut up :)

Well, not exactly.

 

1st - Imagine you are shooting an actual M2 .50 on the ground, trying to hit something at some hundreds of meters;

2nd - Have a light barrel on that HMG which will decrease your accuracy but lighten the recoil (I think?);

3rd - Get you and the gun in movement;

4th - Get your target also moving;

5th - Add thick glass just infront you;

6th - Add the turbulence factor;

7th - Add a general slight shaking everywhere (engines, uneven air, etc.);

8th - Remember you are instructed to only shoot small bursts of 10-15 rounds per gun and have a certain cooldown time (it's stated in various manuals of the time, I'll try to find them);

9th - Even if one bullet hits, it's possible it wouldn't do that much damage, they are just HMG bullets after all, not cannons;

10th - Maybe more stuff I missed?

 

If it was that easy, they wouldn't really need escorts. :thumbup:

11th - if you manage shred that 109/190 despite all this, it won't bring back flashy gun camera footage back to base to be shown weekly on Hitler Channel... the dead tell no tales, same thing with victory reports, only those guys make those who suceeded and survived to tell about it.

Testing done by the USAAF found that the bullet pattern from a B-17 during ground testing had the following results for 12 rounds to 600yds:

ball turret > dia. 15' - 8.3mils

upper turret > dia. 21' - 11.7mils

chin turret > dia. 23' - 12.6 mils

waist(closed) dia. 26' - 14.3mils

side nose > dia. 34' - 18.7mils

tail turret > dia 45' - 25mils

For the B-24 it was:

ball turret > dia. 15' - 8.3mils

upper turret > dia. 20' - 11.2mils

nose turret > dia. 23' - 12.9mils (Emerson)

nose turret > dia. 35' - 19.3mils (Motor Prod.)

waist(closed) dia. 23' - 12.9mils

waist(open) dia. 63' - 35.6mils

tail turret > dia 35' - 19.3mils

from: "Gunner" ISBN 1-55046-332-2

Attacks and hits on B-17s and B-24s, Jan - May 1944

Distribution according to direction of origin in azimuth

B-17 % distribution of 3585 attacks / 441 hits whose direction could be determined

12 - 20.2/15.6

1 - 12.5/9.3

2 - 5.9/6.7

3 - 4.5/3.9

4 - 5.7/4.0

5 - 9.1-9.2

6 - 20.7/15.6

7 - 5.9/6.6

8 - 3.8/2.7

9 - 3.9/2.9

10 - 3.7/3.9

11 - 10.4/10.3

B-24 % distribution of 10425 attacks / 102 hits whose direction could be determined

12 - 21.6/17.6

1 - 12.7/8.4

2 - 3.9/5.2

3 - 2.9/5.4

4 - 3.0/3.6

5 - 7.7/7.8

6 - 20.7/15.6

7 - 19.6/20.6

8 - 11.0/6.9

9 - 3.1/2.0

10 - 6.9/3.4

11 - 11.9/7.8

Note: might not total 100% as the graphic was hard to read

Argh... I'm grinding my teeth away waiting for this to arrive, or at least the startup vids

Argh... I'm grinding my teeth away waiting for this to arrive, or at least the startup vids

I hope I'm wrong but I have the feeling it will be toward the end of the month..

ED please feel free to prove me wrong.