12.8 cm FlaK 40

Development of the 12.8 cm Flak 40 began in 1936, with the contract being awarded to Rheinmetall Borsig. The first prototype gun was delivered for testing in late 1937 and completed testing successfully. The gun weighed nearly 12 tonnes in its firing position, with the result that its barrel had to be removed for transport. Limited service testing showed this was impractical, so in 1938 other solutions were considered. Ultimately the firing platform was simplified, based on the assumption it would always be securely bolted into concrete.{{Clarify|This passage is not congruent. If platform modification was the "solution" the gun would have become properly portable; instead, we are told, first, that guns would instead be bolted solidly in place in concrete, and, second, that guns were paired in twin mounts with a combined weight of over 26 tonnes, making them practically impossible to tow. None of this is congruent with the claim the problem with the gun's size and weight was solved.|date=July 2021}} Approximately 200 guns were also mounted on railcars, providing limited mobility{{Citation needed|date=August 2022}}.

The total weight of the Flakzwilling twin-gun mount system reached 26.5 tonnes,{{Cite book |last=Hogg |first=Ian V. |url=https://books.google.com/books?id=EeYDDQAAQBAJ&dq=Flakzwilling+weight&pg=PT264 |title=German Artillery of World War Two |date=2013-10-12 |publisher=Frontline Books |isbn=978-1-4738-9693-2 |language=en}} making it practically impossible to tow cross-country. In the end, this mattered little since by the time the gun entered production in 1942, it was used in primarily static, defensive applications.{{Cite book |last=Nijboer |first=Donald |url=https://books.google.com/books?id=A0KUDwAAQBAJ&dq=Flakzwilling+entered+production+in+1942&pg=PA25 |title=German Flak Defences vs Allied Heavy Bombers: 1942–45 |date=2019-10-31 |publisher=Bloomsbury Publishing |isbn=978-1-4728-3672-4 |language=en}}

There were four twin mounts on the fortified anti-aircraft Zoo Tower, and they were also on other flak towers protecting Berlin, Hamburg, and Vienna. It is claimed that during the Battle of Berlin the guns on the Zoo Tower were used successfully to support ground forces{{Citation needed|date=August 2022}}. The rush to capture the Reichstag led to dozens of tanks being destroyed.

The gun fired a {{convert|27.9|kg|lb|abbr=on}} shell at {{convert|880|m/s|ft/s|abbr=on}} to a maximum ceiling of {{convert|14,800|m|ft|abbr=on}}. Compared with the 88 mm Flak 18 & 36, the Flak 40 used a powder charge four times as great.

In December 1943, Hitler decided not to introduce the Flak 40 "During this war".{{sfn|Müller|2016|p=51}}{{Clarify|This passage is not congruent with the above content indicating the gun was deployed both in fixed dual mounts and on railcars. Additional context is required.|date=July 2021}}

The Bundeswehr Museum of German Defense Technology in Koblenz has one of these cannons in its collection.

• 12.8 cm Flakzwilling 40/2 The 12.8 cm Flak 40 ordnance on a static dual mounting with a total weight of 26 tonnes, capable of firing 20 rounds per minute. Used mainly on flak towers. Production started in 1942 with 10 tandems produced,Westermann, Edward B. Flak: German Anti-aircraft Defenses 1914–1945 (2005); pp. 108, 128–129. another eight in 1943, and in February 1945 a total of 34 were available.{{Cite web|url=http://www.ww2technik.de/sites/dflak/12,8%20cm%20Flakzwilling.htm|title=12,8 cm Flakzwilling}}
• 12.8 cm PaK 40{{Cite book |last=Wynn |first=Stephen |url=https://books.google.com/books?id=kOJIEAAAQBAJ&dq=12.8+cm+PaK+40&pg=PT20 |title=Hitler's Air Defences |date=2021-11-30 |publisher=Pen and Sword Military |isbn=978-1-5267-4027-4 |language=en}} A derivative anti-tank gun, though rejected in favour of the Krupp 12.8 cm Pak 44 for mass production, but two pieces used to arm the Sturer Emil prototypes.{{Citation needed|date=June 2023}}

{{Gallery|width = 150

|Image:Bundesarchiv Bild 101I-656-6103-09, Reichsgebiet.- Flak-Turm mit schwerer Flak.jpg|12.8-cm-Flak on a flak tower

|Image:128mm Flak 40 Anti-Aircraft railcars at Ploiești cropped.jpg|Railcar-mounted Flak 40 at Ploiești, Romania in 1944

|Image:12.8 cm Flakzwilling 40 1.jpg|Flakzwilling 40 at US Army Ordnance Museum

|Image:Flak 12,8 cm 40-1 in Wehrtechnische Studiensammlung Koblenz.jpg|Flak 40/1 at the Bundeswehr Museum of German Defense Technology

}}

• 120 mm M1 gun, a US gun of almost identical performance{{Citation needed|date=June 2023}}
• QF 4.5-inch gun: British 113 mm heavy anti-aircraft gun firing a slightly lighter shell{{Citation needed|date=June 2023}}
• QF 5.25-inch gun: British 133 mm heavy anti-aircraft gun firing a heavier shell{{Citation needed|date=June 2023}}
• 5"/38 caliber gun: US Navy single/dual purpose shipboard 127 mm heavy anti-aircraft gun firing a slightly lighter shell, used on many U.S. Navy ships built during World War II{{Citation needed|date=June 2023}}

{{Reflist}}

• Gander, Terry and Chamberlain, Peter. Weapons of the Third Reich: An Encyclopedic Survey of All Small Arms, Artillery and Special Weapons of the German Land Forces 1939–1945. New York: Doubleday, 1979 {{ISBN|0-385-15090-3}}
• Hogg, Ian V. German Artillery of World War Two. 2nd corrected edition. Mechanicsville, PA: Stackpole Books, 1997 {{ISBN|1-85367-480-X}}
• {{cite book | last = Hogg | first = Ian V. | author-link = Ian V. Hogg | year = 2002 | title = Anti-aircraft artillery | publisher = Crowood Press | isbn = 1-86126-502-6 }}
• {{cite book |last1=Müller |first1=Rolf-Dieter |author-link=Rolf-Dieter Müller |title = Hitler's Wehrmacht, 1935–1945 |year=2016 |place=Lexington |publisher=University Press of Kentucky |isbn=978-0-81316-738-1 }}

{{Commons category}}

• [http://www.429sqn.ca/flak.htm German Flak]

{{WWIIGermanGuns}}

Category:Anti-aircraft guns of Germany

Category:World War II anti-aircraft guns

Category:128 mm artillery

Category:Rheinmetall

Category:Weapons and ammunition introduced in 1942