Audit on Flak 30 & Flak 38

[Sparre]

I took the liberty to audit the 2 cm Flak 30 and the 2 cm Flak 38. I compared the results with sources in my WWII library. I have 14 books that has data on these two Anti-Aircraft guns. After I checked the sources could I conclude they where consistent with each other. Then did I go Offline to test the two guns to see how they measure compare to the historical real world data.

To sum up, I found that the in-game 2 cm Flak 30 has a too high Rate of Fire (RoF), and that the in-game 2 cm Flak 38 has a too low RoF compare to the historical data. I therefore suggest a few minor changes for both guns.

2 cm Flak 30
1) Rate of Fire, cyclic
The Flak 30 had a historical cyclic RoF of 280 rounds per minute (how fast it takes to empty one magazine). The in-game Flak 30 has a cyclic RoF that is 300 rounds per minute.

Solution: Lower the RoF from 20 rounds per 4 seconds, to 20 rounds per 4.3 seconds (4.2857 seconds), and the gun reach its historical cyclic RoF of 280 rounds per minute.

2) Rate of Fire, practical
The Flak 30 had a practical Rate of Fire that was 120 rounds per minute (how many rounds the gun can fire during constant fire, including reload). The in-game Flak 30 practical RoF are 140 rounds per minute (7 magazine in 1 minute constant firing). In other words, the Flak 30 RoF is too high, firing 1 magazine too many during a one minute cycle.

Solution: If the cycle RoF is decreased to 4.3 (4.2857) seconds per magazine (see above) and at the same time one magazine from the 1 minute cycle is removed, will the Flak 30 gets it historical practical RoF of 120 rounds per minute. At the same time has the reload time be increased slightly. A reload time increase from circa 4,6 seconds to 5,7 seconds. With 6 magazines in 4.3 seconds and 6 reloads in 5.7 seconds will the practical RoF be 120 r/m. This results in 25.8 seconds firing for 6 magazines each minute, and a total of 34.2 seconds reload time each minute.

To sum up:
Decrease each 1 minute cycle to 6 magazines (6 magazines of 20 rounds = 120 r/m)
Increase RoF to 4.3 seconds per magazine
Increase each reload cycle to 5.7 seconds.

Current ingame result
28 s firing 7 magazines
32 s reload –> 7 cycles à 4,57 s

To reach practical RoF 120 r/m should it be:
25,8 s firing 6 magazines (280 r/m cycle)
34,2 s reload –> 6 cycles à 5,7 s

2 cm Flak 38

Rate of Fire, cyclic
The Flak 38 had a historical cyclic RoF of 480 rounds per minute. The in-game Flak 38 has 480 rounds per minute (1 magazine of 20 rounds in 2.5 seconds). Spot On!

Rate of Fire, practical
The Flak 38 had a historical practical Rate of Fire that was 220 rounds per minute.
The in-game Flak 38 fires 180 rounds per minute (63 seconds to be precise) (9 magazine in 1 minute constant firing: 22.5 seconds firing and 37.5 seconds for reloading)

Solution: Add two more magazines per 1 minute cycle to reach the historical practical RoF of 220 rounds per minute.
At the same time shorten the reload time from 4.1666… seconds to 3 seconds (2.9545 s) to make it fit inside the 1 minute cycle (27.5s + 32.5s). Then will the practical RoF for 220 rounds take 60.5 seconds, but I guess we can live with that disparity (or if you can put in the reload time to 2.9545 seconds will it be spot on).

To sump up:
Add 2 magazines to each 1 minute cycle (11 magazine of 20 rounds  = 220 r/m)
Decrease reload time per reload cycle to 2.9545 s (or 3 s).

Current ingame result
22.5 s firing
37,5 s reload –> 9 cycles à 4,1666… s

To reach practical RoF 220 r/m should it be:
27,5 s firing 11 magazines (480 r/m cycle)
32,5 s reload –> 11 cycles à 2.9545 s

 

2 cm Flak 38 on Flakvierling 35 "quadmount"

The above results on 2 cm Flak 38 migrates to the quad mounted 2 cm Flakvierling 35 on Vierling L/38.
I have an ”artifact” from Rheinmetall, an internal document (not published) that seems to be a showcase for costumers, produced around 1942, or maybe 1943. This internal document states the ”2 cm Flak 38 in Flakvierlinglafette” has a practical RoF of 900 r/m. That is a very close number to my other sources that says it had a practical RoF of 880 r/m. If there’s interest can I post pictures of this unique “book” from Rheinmetall’s archives.

 

Sources:
Campbell, John. - Naval Weapons of World War Two (1985/2002)
Chant, Chris. - Artilleri [Swedish translation of ”Artillery”] (2005/2007)
Gander, Terry. and Chamberlain, Peter. Weapons of the Third Reich (1978)
Hogg, Ian V. - Anti-Aircraft Artillery (2002)
Koop, Gerhard. and Schmolke, Klaus-Peter. - German Light Cruisers of of World War II (1983/2002)
Koop, Gerhard. and Schmolke, Klaus-Peter. - Heavy Cruisers of the Admiral Hipper Class (1992/2000)
Koop, Gerhard. and Schmolke, Klaus-Peter. - Pocket Battleships of Deutschland Class (1993/2000)
Koop, Gerhard. and Schmolke, Klaus-Peter. - Destroyers of World War II (2003)
Müller, Werner. - German Medium Flak in Combat (1991)
Trojca, Waldemar. - Ubootwaffe (2004)
Whitley, M.J. - German Cruisers of World War Two (1985)
Whitley, M.J. - German Capital Ships of World War Two (1989/2000)
Whitley, M.J. - German Destroyers of World War Two, 2nd Ed. (1991)
William, Anthoney. - Rapid Fire (2000/2003)
Rheinmetall - Rheinmetall und die Flak (≈1942)

 

Edited October 3, 2020 by Sparre

[BMBM]

Nicely done, thanks.

[drkmouse]

Wow nice wrok