Editing M109 howitzer (section)

==Operational history==
[[File:Dutch M109 155 mm Self-propelled Howitzer Right Side.jpg|thumb|left|Early M109 howitzer of the [[Royal Netherlands Army]]]]

The M109 was the medium variant of a U.S. program to adopt a common [[chassis]] for its self-propelled artillery units. The light version, the [[M108 Howitzer]], was phased out during the [[Vietnam War]], but many were rebuilt as M109s.

The M109 saw its combat debut in Vietnam. Around 200 vehicles were deployed in 1966, but the entire fleet suffered a mechanical malfunction within a year of operation. The U.S. dispatched engineers and mechanics, but all M109s were recalled back to the U.S. in 1967 after failing to repair in the field. The howitzer underwent upgrades afterward, which resulted in the M109A1.<ref name="K55 interview">{{Citation |title=[첨단국가의 초석, 방위산업] 자주포 개발사 - 전설의 시작 K-55 | date=16 September 2015 |url=https://www.youtube.com/watch?v=Iufpdyj0fhk |language=ko |access-date=2022-08-06}}</ref>

Israel used the M109 against Egypt in the 1973 [[Yom Kippur War]] and in the [[1982 Lebanon War|1982]] and [[2006 Lebanon War]]s. Iran used the M109 in the [[Iran–Iraq War]] in the 1980s. The M109 saw service with the [[British Army|British]], U.S. Army, [[Egyptian Army|Egyptian]] and [[Saudi Arabian Army|Saudi Arabian]] Armies in the 1991 [[Gulf War]]. The M109 also saw service with the U.S. Army in the [[Iraq War]] from 2003 to 2011.

Upgrades to the cannon, ammunition, fire control, survivability, and other electronics systems over the design's lifespan have expanded the system's capabilities, including [[W48|tactical nuclear projectiles]], guided projectiles ([[M712 Copperhead|Copperhead]]), [[rocket-assisted projectile]]s (RAP), family of scatterable mines ([[FASCAM]]), and cluster munitions (the [[dual-purpose improved conventional munition]], DPICM).

In August 2015, South Korean K55A1s fired rounds behind the [[Military Demarcation Line]] as a warning after several North Korean provocations.<ref>{{cite web|title=복면지왕, 북한의 양면전술|url=https://h21.hani.co.kr/arti/cover/cover_general/40220.html|access-date=2022-02-17|website=h21.hani.co.kr|language=ko}}</ref>

During the [[Russian invasion of Ukraine]], Ukraine has used M109 howitzers donated by Western countries.<ref>{{Cite web |date=2022-06-09 |title=Norway supplies 22 M109 self-propelled howitzers to Ukraine |url=https://www.army-technology.com/news/norway-m109-self-propelled-howitzers-ukraine/ |access-date=2022-11-05 |website=Army Technology |language=en-US}}</ref> According to video and photographic evidence compiled by the [[open-source intelligence]] website [[Oryx (website)|Oryx]], as of 24 September 2024, at least 70 units of different variants had been lost (54 destroyed and 16 damaged).<ref name="oryx">{{cite web |url=https://www.oryxspioenkop.com/2022/02/attack-on-europe-documenting-ukrainian.html#:~:text=155mm%20M109A3 |title=Attack On Europe: Documenting Ukrainian Equipment Losses During The 2022 Russian Invasion Of Ukraine |last1=Mitzer |first1=Stijn |last2=Janovsky |first2=Jakub |date=June 11, 2024 |orig-date=February 24, 2022 |access-date=11 June 2024 |website=Oryx |publisher=Oryxspioenkop}}</ref>