Kongo class AA shell?

[el cid again]

Or my favorite twist - the "rocket gun" or "gun launched rocket" - a way to get a rocket into the air without a first stage. The latest Chinese version has fully intelligent guided warheads, and also a variant - a recon round! It is supposed to provide real time, hypersonic targeting data for the attack to follow (in a few minutes) on a US formation at ranges greater than any weapon in any US formation can fire. We are talking 600 km for an artillery weapon. The primary round has something like 42 sub munitions. Given the beaste is something like 16 inch caliber - these are respectable size in their own right.

[witpqs]

ORIGINAL: mlees

But anyway, IMO, a 10% success rate is not something to crow about.

This makes me wonder - does anybody know roughly what percentage of attacking aircraft hit a ship with either bombs, torpedoes, or rockets? I'm leaving out missiles on purpose, but if you know that separately, that would be interesting too.

[el cid again]

It depends on conditions. Lots of factors. Working up for Midway - the Kates under Capt Fujida achieved an astonishing hit rate - probably the best for non-smart weapons ever: horizontal bombers with 800 kg bombs from altitude (so they had the energy to penetrate a deck) could hit a target 85% of the time per element of 5 - that is 17% per aircraft. Now that is in practice, with no one shooting at them. You can take the number of Kates at PH armed with 800 kg bombs and the number of hits by them to work out the actual value - and it probably will still be the record for horizontal bombing.
I have some ballistic tables somewhere I will see if I can find. Low altitude helps. Dive bombing and glide bombing help.
But the % is awfully low - and for horizontal bombers vs defended targets always well below that 10% figure. 10% may sound bad - yet it was achieved mostly with obsolete aircraft and green pilots - and it is better than what skilled pilots in good planes usually achieve. Kamakazes should be able to do better than that if you could motivate experienced pilots and give them new planes. But it is a waste of both pilots and planes - and I don't believe in it as a force tactic. Its great value might be in its propaganda/terrorist aspects: say they were running into ocean liners, tankers, or ships loaded with troops headed to Taiwan - it might affect popular reaction to the war.

[Dili]

Italian torpedo bombers in 1941 got 8 torpedo hits per aircraft lost. In 1943 that reduced to 2,5-3 hits.

[el cid again]

But what was the rate per sortee?

[DuckofTindalos]

Sid, have you got any source material on this 15cm Flak 39 you posted about earlier? The heaviest LW flak I've heard of to date was the 12.8cm Flak 40.

EDIT: did some more digging, and the only 15cm LW Flak I could find was something called the "Gerät 50" which saw nearly no service. The Germans seem to have discovered that the 15cm wasn't a big enough improvement on the 12.8cm to warrant retooling for mass production.

[m10bob]

ORIGINAL: Terminus

Sid, have you got any source material on this 15cm Flak 39 you posted about earlier? The heaviest LW flak I've heard of to date was the 12.8cm Flak 40.

EDIT: did some more digging, and the only 15cm LW Flak I could find was something called the "Gerät 50" which saw nearly no service. The Germans seem to have discovered that the 15cm wasn't a big enough improvement on the 12.8cm to warrant retooling for mass production.

Here ya go, friend:

http://www.lonesentry.com/manuals/germa ... _guns.html


http://www.axishistory.com/index.php?id=1271

[DuckofTindalos]

Excellent stuff, Bob! Thank you.[&o]

[Dili]

But what was the rate per sortee?

 
Didnt have that info. 

[el cid again]

This gives a very simplified sense of the factors which matter in air attacks: you can see that there is a lot more to it than the type of aircraft. The mission approach profile has a profound influence on the outcome. So does the existence of air defenses. So does the existence of a spotter/controller for the operation. [This was a WWII era Japanese concept: Fujida controlled the strikes at Pearl Harbor, beginning to end, determining which of several drilled attack options to use, from a Kate, which was the last plane to land, having led stragglers without navigation instruments back to the carriers. There may have been a controller at Clark - the most accurate bombing mission of WWII.] So does pilot experience rating. Today also the nature of the weapons is more complex than it was in WWII: but even then primitive smart munitions existed (see B-24s operational use of BAT for example). Even statistical data from real world missions in a shooting war in sufficient numbers to be valid (minimum 30 cases) is going to be heavily influenced by the actual profile of the attacks chosen, the nature of the air defenses, and the experience of the air crews. The very same aircraft in different conditions will achieve a very different score. [This is a table of modifiers for a decimal die roll when using an air CRT]



Table 4A: Combat Modifiers for Air Attacks [Rev. 8.82] © Sid Trevethan June 2005

Attack Profile Altitude Range Air Spotter No Air Spotter Anti-Ship
Dive Bombing 3 km to 1 kilometer 0 +3 0 +1
Glide Bombing, Low Altitude 2 km to 1 kilometer 0 +3 0 +2
Glide Bombing, Medium Altitude 3 km to 2 kilometer 0 +2 -1 0
Level Bombing, Very Low Altitude 50 (1 - 99 ) meters 0 0 -3 - 1
Level Bombing, Low Altitude 500 (100 – 999) meters 0 +1 -2 0
Level Bombing, Medium Altitude 3 (1 - 5) kilometers 0 0 -3 - 2
Level Bombing, High Altitude 8 (5.001 - 11) kilometers 0 -1 -4 - 3
Level Bombing, Very High Altitude 15 ( 11,001+) kilometers 1 -3 -6 - 5
Strafing or Naval Rocket Attack 50 (1 - 99 ) meters 0 +3 0 +2
Toss Bombing, End @ High Altitude 8 (5.001 - 11) kilometers 0 -5 -8 - 7

Note 1: If multiple elements perform an air attack mission as a squadron, add the square root of the number of air elements to the modifier (drop fractions) = for 2 or 3 add 1, for 4-8, add 2, for 9+ add 3.
Note 2: Pilot effectiveness level modifier: If the PEL of the attacking air elements is 5 or more, add 1;
If the PELof the attacking air elements is 3 or 4, no modifier.
If the PEL of the attacking air elements is less than 3, subtract 1.
Note 3: Defensive fire modifier: If the attacking air elements were fired upon by LAA, HAA, SAMs or an enemy air combat
mission, subtract 1 from the modifier for each (cumulative).
Note4: If laser guided bombs are used by attacking air elements in hexes where there is no cloud cover, storms or fog
add 4 to the modifier.
Note 5: Toss bombing profile involves a low altitude approach and ends with the aircraft at high altitude
opening the range to the target after tossing the bomb. Instead of passing over the target after bomb
delivery, the aircraft actually leaves the target in the same direction from which it came.
Note 6: If GPS guided bombs (including JDAM) are used against a fixed target of known position, add 3 to the modifier.
Note 7: Unspotted target: only fixed unspotted targets may be attacked. Moving unspotted targets may not
be attacked.
Note 8: Air elements performing the tactical airs support function must use dive bombing, glide bombing low altitude,
level bombing high altitude withlaser guided bombs, level bombing medium altitude with GPS guided bombs or strafing
attack profiles.

[el cid again]

Here is the actual table for ship attacks: [For reasons unclear each column posts separately instead of side by side]
Notice modifiers here for target speed: different targets will produce different results for the same attack aircraft and profile - some targets are larger, some are slower, etc.

Table 13: Anti-Ship Combat Results Table [Rev. 8.60]© Sid Trevethan June 2005

ADSAMSS, ASCM or ASBM Factor, Bomb Factor, BVR Factor, Helo Attack Factor or Naval Gun Factor

Corrected
Die Roll
1 - 2

3 - 4
5 - 6
7- 8
9-10

11-12
13-14
15-16
17-18
19-20
21-22
23-24
25+

0 (or less)
NE
NE
NE
NE
NE
1
1
1
1
2
2
2
3

1
NE
NE
NE
NE
1
1
1
1
2
2
2
3
3

2
NE
NE
NE
1
1
1
1
2
2
2
3
3
4

3
NE
NE
1
1
1
1
2
2
2
3
3
4
4

4
NE
1
1
1
1
2
2
2
3
3
4
4
4

5
1
1
1
1
2
2
2
3
3
4
4
4
4

6
1
1
1
2
2
2
3
3
4
4
4
4
4

7
1
1
2
2
2
3
3
4
4
4
4
4
4

8
1
2
2
2
3
3
4
4
4
4
4
4
4

9
2
2
2
3
3
4
4
4
4
4
4
4
4

10
2
2
3
3
4
4
4
4
4
4
4
4
4

11 2
3
3
4
4
4
4
4
4
4
4
4
4

12
3
3
4
4
4
4
4
4
4
4
4
4
4

13
3
4
4
4
4
4
4
4
4
4
4
4
4

14 and up
4
4
4
4
4
4
4
4
4
4
4
4
4
Roll once per shot of missiles, once per element of aircraft, or once per round of gunfire.
Result: The number of hits on task group where NE = No Effect.
For combat within visual range, apply result after both sides attack.

Note 1: Add the attacking electronic warfare level to the die roll.
Note 2: Subtract the defending electronic warfare level from the die roll.
Note 3: For missile attacks and all attacks at night or in fog, the side with the higher EW level chooses the first target hit.
Note 4: If EW levels are identical, or if it is the third target hit, the target is randomly selected from the largest
unhit targets available, in order CV, LH, MJO, MKHL, AKRR, AKCR, LS, FS, MS, FPB, SPB, submarine.
Note 5: For missile attacks only, even numbered (i.e. second and fourth) hits seek targets on fire, or the largest
unhit targets available, in order CV, LH, MJO, MKHL, AKRR, AKCR, LS, FS, MS, FPB, SPB, submarine.
Note 6: For air attacks, add attack profile modifier to the die roll: See Table 4A.
Note 7: If laser guided bombs are used by the attacking air elements on day turns with no cloud cover or fog
obscuring the target, add +4 to the die roll.
Note 8: For targets moving at speeds of 6 through 11, add -1 to the die roll.
Note 9: For targets moving at speeds of 12+, add -2 to the die roll.
Note 10: If JDAM command bombs are used by the attacking air elements, add +3 to the die roll.
Note 11: Land units and naval units which are out of AMMO may not conduct anti-ship attacks.

[Mike Scholl]

ORIGINAL: m10bob
Here ya go, friend:

http://www.lonesentry.com/manuals/germa ... _guns.html

http://www.axishistory.com/index.php?id=1271

Bob..., do you have anything else on the 150mm aa. That muzzle velocity (3450 fps) is pretty unbelievable. What was the barrel life on that thing? 15-20 rounds?

[m10bob]

Different gun, but same source,(from wartime publications and intel bulletins):

http://www.lonesentry.com/articles/ttt/ ... k-gun.html

Sames source, only mention of belief it was used for protection of Germany itself:

http://www.lonesentry.com/manuals/tme30 ... 4sub7.html

[el cid again]

Most high velocity rifles (from the kind you carry up through big naval guns) have mv on the order of 2700 fps. But the theoretical practical upper bound for a full caliber round without wierd engineering is 3600 fps. For a sub caliber device, where the sub caliber is 0.73333 the diameter of the rifle caliber, the theoretical practical upper bound is 4200 fps. To go beyond that requires something strange, like the "high pressure pump" (multiple firing chambers and an ultra long barrol) or rocket assisted projectiles. Normal rifles have barrol lengths in the 40 to 60 caliber range - and they can be moved with reasonable effort. Rifles with much longer barrols are generally built into place or have to be assembled before use, and cannot be considered for any application like AAA. Within that range, mv is related to things like the charge and the weight of the projectile, and the pressure that can be tolerated. But any value up to about 3600 fps is not "unbelievable" in normal rifle engineering. For everything there is a price - and really high performance weapons pay it in barrol life. The Paris Gun (press name, actually Kaiser William Geshutz) had to use DIFFERENT ammunition for EACH shot: a barrol could only fire about 42 times, and each round came with its firing order painted on it - because each shot ate up a predictable amount of the barrol. If you keep pressures in reasonable bounds (and performance moderate) you should achieve hundreds of rounds before wearing out the barrol: in 1968 USS Iowa calculated it could fire almost 300 times per tube before the liners were worn excessively - and we had a spare set at Subic in case we needed to change them out - so we were told at the time.

[Mike Scholl]

ORIGINAL: m10bob

Different gun, but same source,(from wartime publications and intel bulletins):

http://www.lonesentry.com/articles/ttt/ ... k-gun.html

Sames source, only mention of belief it was used for protection of Germany itself:

http://www.lonesentry.com/manuals/tme30 ... 4sub7.html

Bob. Wasn't doubting it's existance in at least some small quantity..., just questioning the extraordinary muzzle velocity quoted in your source. Looks more like a misprint than a fact.

[m10bob]

ORIGINAL: Mike Scholl

ORIGINAL: m10bob

Different gun, but same source,(from wartime publications and intel bulletins):

http://www.lonesentry.com/articles/ttt/ ... k-gun.html

Sames source, only mention of belief it was used for protection of Germany itself:

http://www.lonesentry.com/manuals/tme30 ... 4sub7.html

Bob. Wasn't doubting it's existance in at least some small quantity..., just questioning the extraordinary muzzle velocity quoted in your source. Looks more like a misprint than a fact.

No Mike..we're fine...I'm just upset I can't seem to find anymore to satisfy your very legit question.....I have some books at home which might have an answer, but that is hours away....

[el cid again]

When I get home I will look in a list of all artillery pieces in my files taken from a British publisher. It might also be in Campbell - if these were used for CD they should be. To confirm the data is not a misprint - or is.

My artillery file set - sent by a British author - seems to be missing the page listing data for German Heavy Flak. But the German "Light Anti-tank" (if this stuff is light, wow) page does show German FLAK guns had high velocities: PAK 40 comes in at 3250 fps (980 m/s); PAK 36 comes in at the same value; PAK 41 comes in at 3690 fps (1125 m/s) - and is above the range I described as "normal" above. This was with a 4.53 kg shell (10.01 pounds) - a peculiar hollow charge shell - for a 7.5 cm gun. The German "Medium FLAK" page shows FLAK 58 at 3445 fps (1040 m/s) and FLAK 41 (the 8.8 cm one, not the 5 cm one) at 3280 fps (1000 m/s). Clearly velocities over 3000 fps were routine for wartime German high performance rifles. Wierd "taper bore" guns reached as high as 4593 fps (1402 m/s).

Aha - I found it - on the wrong page - with AT guns "15cm FLAK": 3600 fps (1100 m/s). That is actually higher by 150 than the web site listed above shows. This is small enough it may be a matter of the specific round or charge used - but it is certainly in the same range.

[el cid again]

As long as we must work on artillery devices anyway - we should work this in.

I am going to assume that AA shells for UltraHeavy guns not otherwise fitted to be AA are ceiling limited to 1/3 of theoretical effective altitude
EDIT: This works only if we assume effective altitude is 50% of maximum shell height on a long range shot = 1/12 of full range of the gun.


that AA shells for DP guns limited to 75 degree elevation is 2/3 of their theoretical effective altitude

and that true AA guns which elevate to 90 degrees get full effective elevation.

AA guns and DP guns are range limited to the range = effective ceiling (to the nearest thousand yards)

but ultra heavy guns are not so limited - so they remain mainly SP guns

The ultra heavies are not very effective (in this case meaning the effect value in the game - not just IRL), so they won't often score - and then only at lower altitudes. Since they cannot elevate or traverse rapidly, they would really matter only against a large formation pressing in constant bearing decreasing range - if the ship was not turning - something that Hara did with a DD with generally ineffective Long 50 caliber 5 inch guns - baggind a single attacker on his first attempt. The stable gun platform vs a stable target at low altitude permitted a fire control solution that worked.

[Mike Scholl]

ORIGINAL: el cid again

When I get home I will look in a list of all artillery pieces in my files taken from a British publisher. It might also be in Campbell - if these were used for CD they should be. To confirm the data is not a misprint - or is.

My artillery file set - sent by a British author - seems to be missing the page listing data for German Heavy Flak. But the German "Light Anti-tank" (if this stuff is light, wow) page does show German FLAK guns had high velocities: PAK 40 comes in at 3250 fps (980 m/s); PAK 36 comes in at the same value; PAK 41 comes in at 3690 fps (1125 m/s) - and is above the range I described as "normal" above. This was with a 4.53 kg shell (10.01 pounds) - a peculiar hollow charge shell - for a 7.5 cm gun. The German "Medium FLAK" page shows FLAK 58 at 3445 fps (1040 m/s) and FLAK 41 (the 8.8 cm one, not the 5 cm one) at 3280 fps (1000 m/s). Clearly velocities over 3000 fps were routine for wartime German high performance rifles. Wierd "taper bore" guns reached as high as 4593 fps (1402 m/s).

Aha - I found it - on the wrong page - with AT guns "15cm FLAK": 3600 fps (1100 m/s). That is actually higher by 150 than the web site listed above shows. This is small enough it may be a matter of the specific round or charge used - but it is certainly in the same range.

All those numbers seem high, Cid. Are you sure you aren't quoting MV's for the sub-calibre tungsten- cored AP rounds?

[m10bob]

BTW, according to Richard B Frank,(GUADALCANAL), the fisrt American naval VT aa round to down an enemy plane was a Val in the first week of Jan 1943, from a 5" gun..(I had not realized they were available that early.)