88 Ack Gun Settings

[SKJohn]

I have a question I got mixed answers in game today.  Say I'm sitting in an 88mm Ack gun.  A flight of bombers is coming in and their icon range says 6K.
Since the range of the 88 is given in yards, do I set it for 2K (2000 yds = 6000 ft), or 6K.

I guess the real question is, when you are in an ack gun, is the range you see on the aircraft icons given in yards or feet?  Is it considered ALTITUDE or DISTANCE to target?

[Lusche]

Icons are always given in yards and show the distance to the target.

[bustr]

How much time does it take B24's to travel 1000yards?
250mph equals 366.6ft\sec or approx 122 yards per second.
250mph is approx 8sec for 1000 yards.

How long does it take your round to travel 5000 yards? About 5 seconds and a smidge longer?

For every 1000ft of elevation at 5000 yards how much elevation do you add in your sighting? Or are the B24 flying directly at your position? Then how far ahead of the line of flight do you lead? Or are they flying directly away or are they flying parallel to your position?

At 6000 yards what is the diameter of your aiming circle relative to the distance? How many yards in diameter is the circle at 6000yds and 5000yds? You can probably use the offline target to determine the diameter of the circle at different ranges. Oh how I wish we had a 1000yd fuse for the 88 round to deal with low level base hoarders or the allied ack using proximity fuzes that defeated the doodlebugs......

88 muzzel velocity is 2890ft\sec.
2890 feet = 963 yards per second.

I'm sure there is a VLoss per 1km factor for the round but, on rule of thumb average, if you count verbaly by (One.one-thousand) and so forth it takes one of those for every 1000 yards you set the fuse.

[SKJohn]

Icons are always given in yards and show the distance to the target.

That's what I thought, but there's one of those little tip things that comes up when you sign in that says something about altitude in feet and distance in yards, or something like that.  By the time I think of grabbing something to write it down with, it has already disappeared. 

[shotgunneeley]

Elevation is in feet (or k-feet), distance is in yards (or k-yards). Try this table I made:

http://www.mediafire.com/?pc3ufdb7dgqjd

The .xls is for microsoft excel 2007 and newer, .xlsx is for microsoft excel 2003. At a base of 0 elevation, I measured the flight time and amount of drop for the shell to explode at the every #.0 and #.5 fuse length (then ran a regression equation to best fill the lengths in between). For each of the 4 engine heavy bombers, I calculated the speed (in k-yards/second) at 5 thousand foot intervals (starting at sea level) using the AH speed charts.

Assuming the target is flying straight at you at the speed indicated by the AH chart, I determined the fuse length necessary to hit the target when it is at the fuse lengths distance.

(e.g., A set of b-17's is traveling directly at your flak 88 position at an altitude of 15k feet. When the direct line of sight distance between you and the target is 8.9 k-yards, you should fire a shell length of 7.2. Given the rate of the target coming to you and the rate of the shell going to it, the target will be at a distance of 7.2 k-yards when the shell explodes.)

The amount of lead to give the target is completely up to the gunner. It will take the shell 13.1 seconds and 1.5 cm of drop to get to 7.2 k-yards. So you'll want to aim where you think the target will be 13.1 seconds into the future, then add an additional 1.5cm.

Granted, this test was done at 0.0k at a rough barrel angle of 45 degrees. I haven't had very good luck with this system because by the time you make the setting corrections manually, the target has changed distance and your solution is obsolete by the time you fire. Not knowing the precise elevation, speed or trajectory of the target or even the angle or orientation of the gun greatly hampers your effectiveness.

I've seen some guys come impressively close to my formations, though. Even at 20k I've been able to here the puffs, but with only 1 gun firing and the large amount of error caused by the unknown variables makes this unconcerning.