Editing M1 Abrams (section)

===Mobility===

====Tactical====
[[File:AGT1500 engine and M1 tank.JPEG|thumb|Marines from 1st Tank Battalion load a [[Honeywell AGT1500]] multifuel turbine back into a tank at Camp Coyote, Kuwait, February 2003.]]
{{see also|AGT1500}}

The M1 Abrams's [[powertrain]] consists of an AGT1500 [[multifuel]] gas turbine (originally made by [[Lycoming Engines|Lycoming]], now [[Honeywell]]) capable of {{convert|1500|shp|kW|sp=us}} at 30,000 [[Revolutions per minute|rpm]] and {{convert|395|lb·ft|Nm|abbr=on}} at 10,000 rpm and a six-speed (four forward, two reverse) [[Allison Transmission|Allison]] X-1100-3B Hydro-Kinetic [[automatic transmission]]. This gives it a governed top speed of {{convert|45|mph|km/h|abbr=on}} on paved roads, and {{convert|30|mph|km/h|abbr=on}} cross-country. With the engine governor removed, speeds of around {{convert|60|mph|km/h|abbr=on}} are possible on an improved surface. However, damage to the drivetrain (especially to the tracks) and an increased risk of injuries to the crew can occur at speeds above {{convert|45|mph|km/h|0|abbr=on}}.

The tank was built around this engine and it is multifuel-capable, including diesel, gasoline, [[marine diesel oil|marine diesel]] and [[jet fuel]] (such as [[JP-4]] or [[JP-8]]).<ref>{{Cite web |url=http://www.honeywell.com/sites/aero/Turboprops3_CDF1BA7AE-8A37-9A78-EC1A-E00A4B74F3E9_H52422376-8368-1EC3-AA6D-83165D399CBF.htm |title=Honeywell Aerospace – AGT1500 |access-date=21 January 2023 |archive-date=8 March 2008 |archive-url=https://web.archive.org/web/20080308153949/http://www.honeywell.com/sites/aero/Turboprops3_CDF1BA7AE-8A37-9A78-EC1A-E00A4B74F3E9_H52422376-8368-1EC3-AA6D-83165D399CBF.htm |url-status=dead}}</ref><ref>{{cite web |url=http://www.accessmylibrary.com/coms2/summary_0286-17629659_ITM |title=Heavy duty: overhaul under way for Abrams tank engine |publisher=Accessmylibrary.com |date= 1 September 2006 |access-date= 9 June 2009 |url-status=dead |archive-url=https://web.archive.org/web/20090111230441/http://www.accessmylibrary.com/coms2/summary_0286-17629659_ITM |archive-date=11 January 2009}}</ref><ref>{{cite news |last1=Roblin |first1=Sebastien |title=The US's powerful Abrams tanks are heading to Ukraine, but generals disagree over how hard it'll be to use them on the battlefield |url=https://www.businessinsider.com/generals-disagree-on-difficulty-of-using-abrams-tanks-for-ukraine-2023-2 |work=Business Insider |agency=19fortyfive |publisher=Insider |date= 1 February 2023 |access-date= 2 April 2025}}</ref> In the AGT1500, jet fuel has poorer fuel economy and operating range compared to diesel. By 1989, the Army was transitioning solely to JP-8 for the M1 Abrams, part of a plan to reduce the service's [[logistics]] burden by using a single fuel for aviation and ground vehicles.<ref>{{cite news |last1=Evans |first1=David |title=Tanks Running on Poor Ideas and Bad Planning |url=https://www.chicagotribune.com/news/ct-xpm-1989-09-01-8901090654-story.html |access-date=21 January 2023 |work=Chicago Tribune |publisher=Tribune Publishing |date=1 September 1989}}</ref> The Australian M1A1 AIM SA burns diesel fuel, since the use of JP-8 is less common in the Australian Army.{{citation needed|date=March 2023}}

[[File:M1a1 drivers hole.jpg|thumb|left|M1A1 driving controls]]
[[File:M1A1 auxiliary power unit Saudi Arabia.jpg|thumb|left|An American M1A1 fitted with an external [[auxiliary power unit]] in Operation Desert Storm.]]
The gas turbine propulsion system has proven quite reliable in practice and combat, but its high fuel consumption is a serious logistic problem.<ref name=autogenerated1/> It burns between 1.5 and 3 gallons per mile.<ref>{{Cite news |last=Jon |first=Jackson |date=2023-01-25 |title=Game-changing Abrams tanks present one glaring problem for Ukraine |url=https://www.newsweek.com/us-abrams-tanks-fueling-problems-ukraine-1776639 |access-date=2024-09-10 |publisher=[[Newsweek]] |language=en}}</ref>

The turbine is very quiet when compared to diesel engines of similar power output and produces a high-pitched whine, reducing the audible distance of the sound, thus earning the Abrams the nickname "whispering death" during its worldwide debut at the 1982 [[Reforger]] exercise.{{sfn|Kelly|1989|p=267}}<ref name=Grummitt>{{cite book |last1=Grummitt |first1=David |title=M1 Abrams: The U.S's Main Battle Tank in American and Foreign Service, 1981–2019 |year=2019 |publisher=Pen & Sword |location=South Yorkshire |isbn=978-1-526749772 |url=https://books.google.com/books?id=hOMSEAAAQBAJ&dq=%22whispering+death%22+reforger&pg=PT37 |access-date=8 January 2024}}</ref>

By the time production of the AGT1500 ended in 1994, the U.S. had purchased 12,000 such engines. In 2006 the Army awarded Honeywell a contract to overhaul 1000 engines, with options for up to 3000 more.<ref>{{cite news |title=Overhaul under way for Abrams tank engine |url=https://www.nationaldefensemagazine.org/articles/2006/9/1/2006september--overhaul-under-way-for-abrams-tank-engine |access-date=5 June 2024 |work=www.nationaldefensemagazine.org |date=1 September 2006}}</ref>

The Army received proposals, including two diesel options, to provide the common engine for the [[XM2001 Crusader]] and Abrams. In 2000, the Army selected the gas turbine engine LV100-5 from Honeywell and subcontractor [[General Electric]].<ref name="Honeywell selected">{{cite news |last1=Dupont |first1=Daniel G. |title=Tanks Won't Be Converted to Diesel: Honeywell Turbine Engine Picked for Abrams Fleet, Crusader System |url=https://www.jstor.org/stable/43985032 |access-date=7 February 2022 |work=Inside the Army |issue=38 |publisher=Inside Washington Publishers |date=25 September 2000 |volume=12 |pages=1, 11 |jstor=43985032 |archive-date=7 February 2022 |archive-url=https://web.archive.org/web/20220207070455/https://www.jstor.org/stable/43985032 |url-status=live}}</ref> The new LV100-5 engine was smaller (43% fewer parts) with rapid acceleration, quieter running, and no visible exhaust.<ref>{{cite web |url=http://www.geae.com/engines/military/lv100/index.html |title=GE – Aviation: LV100 |access-date=7 August 2008 |url-status=dead |archive-url=https://web.archive.org/web/20080607052044/http://www.geae.com/engines/military/lv100/index.html |archive-date=7 June 2008}}</ref> It also featured a 33% reduction in fuel consumption (50% less when idle) and near drop-in replacement.<ref>{{cite web |url=http://www.geae.com/engines/military/lv100/spotlight_advantages.html |title=GE – Aviation: LV100 Advantages |access-date=7 August 2008 |url-status=dead|archive-url=https://web.archive.org/web/20080618180930/http://www.geae.com/engines/military/lv100/spotlight_advantages.html |archive-date=18 June 2008}}</ref> The Common Engine Program was shelved when the Crusader program was canceled. Phase 2 of Army's PROSE (Partnership for Reduced O&S Costs, Engine) program, however, called for further development of the LV100-5 and replacement of the current AGT1500 engine.<ref>{{cite web |url=http://www.defenseindustrydaily.com/aim-programs-m1a1-tank-refits-and-rebuilds-continue-0440/ |title=AIM Program's M1A1 Tank Refits and Rebuilds Continue |publisher=Defenseindustrydaily.com |date=2 May 2005 |access-date=9 June 2009 |url-status=live |archive-url=https://web.archive.org/web/20090714194319/http://www.defenseindustrydaily.com/aim-programs-m1a1-tank-refits-and-rebuilds-continue-0440/ |archive-date=14 July 2009}}</ref>

[[File:US Navy 031214-N-3236B-008 A Marine from the 13th Marine Expeditionary Unit (13th MEU) Tank Platoon BLT 1-1 stationed at Twentynine Palms, Calif., directs an M1-A1 Abrams tank during a training exercise.jpg|thumb|A U.S. Marine M1A1 fitted with snorkel attachment and [[bustle rack]] extension.]]
From 1991 to 1994, the Army fitted 1,500 Abrams turrets with external [[auxiliary power unit]]s (APU). APUs allow some the Abrams to run some functions without running on the engine. Some Abrams tanks that saw service during the Gulf War were fitted with such a device.{{sfn|Zaloga|2009|p=20}} Although the Army favored an under-armor APU, Congress instead funded a short-term modification to 336 M1A2 Abrams. These were installed in 1997.{{sfn|Zaloga|2009|p=19}} An under-armor APU located in the hull was chosen for the M1A2 SEP variant. When this proved unreliable, it was replaced with a battery-based Alternate APU starting in 2005.{{sfn|Zaloga|2009|p=20}}

[[File:White Falcons Integrate Armor Support for Combined Arms Live Fire Exercise in New Mexico 150930-A-DP764-009.jpg|thumb|[[82nd Airborne Division|82nd Airborne]] [[paratrooper]]s ride on an M1 Abrams by [[tank desant]].]]
Although the M1 tank is not designed to carry riders easily, provisions exist for the Abrams to transport troops in [[tank desant]] with the turret stabilization device switched off. A battle-equipped infantry squad may ride on the rear of the tank, behind the turret. The soldiers can use ropes and equipment straps to provide handholds and snap links to secure themselves.<ref name="passenger">{{cite book |title=U.S. Army Warrior Ethos And Combat Skills Handbook (Field Manual No. 3‑21.75) |year=2009 |publisher=Morris Book Publishing, LLC |isbn=978-1-59921-819-9 |url=https://rdl.train.army.mil/soldierPortal/atia/adlsc/view/public/24572-1/FM/3-21.75/ |chapter-url=https://rdl.train.army.mil/soldierPortal/atia/adlsc/view/public/24572-1/FM/3-21.75/chap7.htm |author=Department of the Army |access-date=2 June 2010 |chapter=7 |url-status=dead |archive-url=https://web.archive.org/web/20110720003542/https://rdl.train.army.mil/soldierPortal/atia/adlsc/view/public/24572-1/FM/3-21.75/ |archive-date=20 July 2011}}</ref><!-- A statement about how often this is actually used would be good, if a source is available for that, thanks. -->

The Abrams T156 is a permanently bonded rubber track pad, a distinctive feature not found on any other tank. Unlike other tanks with replaceable track pads, on the Abrams, a worn track pad is remedied by replacing the entire track shoe. The Abrams non-removable track pads save weight but are less desirable in snow as the pads cannot be replaced with [[grouser]]s.<ref>{{cite journal |last1=Williams |first1=Greg |title=The Army's M1 Tank: Has It Lived Up To Expectations? |journal=POGO |date=12 June 1990 |url=https://www.pogo.org/reports/armys-m1-tank-has-it-lived-up-to-expectations |access-date=27 December 2023}}</ref> As of 2007, M1 Abrams track wear constitutes the second-largest consumable expense in the U.S. Army, surpassed only by [[Meals, Ready to Eat]] consumption.<ref>{{cite journal |last1=Harris |first1=Lieutenant Colonel Benjamin |title=King of the Killing Zone: How Well Has It Held Up? |journal=Armor |issue=July–August 2007 |pages=18–20 |url=https://www.moore.army.mil/armor/eARMOR/content/issues/2007/JUL_AUG/ArmorJulyAugust2007web.pdf |archive-url=https://web.archive.org/web/20231227031845/https://www.moore.army.mil/armor/eARMOR/content/issues/2007/JUL_AUG/ArmorJulyAugust2007web.pdf |url-status=dead |archive-date=27 December 2023 |access-date=27 December 2023}}{{Source-attribution}}</ref> In 1988 the Army awarded [[FMC Corporation]] a contract for T158 tracks rated for {{convert|2100|miles}}, or about double the life of the previous shoe.{{sfn|Kelly|1989|pp=244–245}} These feature replaceable pads and are about 3000 pounds heavier.{{sfn|Hunnicutt|2015|p=248-249}} The driver is equipped with a thermal viewer. On at least some models this is the Hughes AN/VAS-3.{{sfn|Cullen|Foss|1997|p=424}}

====Strategic====
[[File:DF-SD-06-12692.jpg|thumb|A U.S. Army M1A1 after being offloaded from a U.S. Air Force [[C-17 Globemaster III|C-17]] at [[Balad Air Base]], Iraq in 2004]]
[[File:M1 strategic mobility.jpg|thumb|A Marine M1A1 offloading from a [[Landing Craft Air Cushioned]] vehicle]]

Strategic mobility is the ability of the tanks of an armed force to arrive in a timely, cost effective, and synchronized fashion. The Abrams can be carried by a [[C-5 Galaxy]] or a [[C-17 Globemaster III]]. The limited capacity (two combat-ready tanks in a C-5, one combat-ready tank in a C-17) caused serious logistical problems when deploying the tanks for the first Gulf War, though there was enough time for 1,848 tanks to be transported by ship.

The Marines transported their [[Marine Air-Ground Task Force]] Abrams tanks by combat ship. A ''[[Wasp class amphibious assault ship|Wasp]]''-class [[Landing Helicopter Dock]] (LHD) typically carried a platoon of four to five tanks attached to the deployed [[Marine Expeditionary Unit]], which were then amphibiously transported to shore by [[Landing Craft Air Cushion]] (LCAC) at one combat-ready tank per landing craft.

The Abrams is also transportable by truck, namely the [[Oshkosh M1070]] and M1000 [[Heavy Equipment Transporter System]] (HETS) for the US Military. The HETS can operate on highways, secondary roads, and cross-country. It accommodates the four tank crew members.<ref>{{cite web |url=http://www.army.mil/factfiles/equipment/wheeled/m1070.html |title=M1070 Heavy Equipment Transporter (HET) Fact File United States Army |publisher=Army.mil |access-date=30 June 2010 |url-status=dead |archive-url=https://web.archive.org/web/20100706020118/http://www.army.mil/factfiles/equipment/wheeled/m1070.html |archive-date=6 July 2010}}</ref> The Australian Army uses customized [[MAN SE|MAN]] trucks to transport its Abrams.<ref>{{cite news |title=Enter the Abrams |url=https://www.australiandefence.com.au/D4B755E0-F806-11DD-8DFE0050568C22C9 |access-date=31 August 2021 |work=Australian Defence Magazine |date=10 January 2008 |language=en |archive-date=31 August 2021 |archive-url=https://web.archive.org/web/20210831233756/https://www.australiandefence.com.au/D4B755E0-F806-11DD-8DFE0050568C22C9 |url-status=live}}</ref>

The first instance of the Abrams being airlifted directly into a battlefield occurred in October 1993. Following the [[Battle of Mogadishu (1993)|Battle of Mogadishu]], 18 M1 tanks were airlifted by C-5 aircraft to Somalia from [[Hunter Army Airfield]], Georgia.<ref>{{cite news |last=Haulman |first=Daniel L. |title=The United States Air Force In Somalia, 1992–1995 |url=http://www.dafhistory.af.mil/Portals/16/documents/Airmen-at-War/Haulman-USAFSomalia1992-1995.pdf?ver%3D2016-08-22-131410-337&usg=AFQjCNFCsGZTGkPjFg1zB2quBMa5EMKI-A |access-date=28 September 2017 |archive-url=https://web.archive.org/web/20170928193337/http://www.afhra.af.mil/Portals/16/documents/Airmen-at-War/Haulman-USAFSomalia1992-1995.pdf?ver%3D2016-08-22-131410-337&usg=AFQjCNFCsGZTGkPjFg1zB2quBMa5EMKI-A |archive-date=28 September 2017 |url-status=live}}</ref><ref>{{cite news |last=Leland |first=John W. |title=The Chronological History Of The C-5 Galaxy |url=https://www.amc.af.mil/Portals/12/documents/AFD-131018-052.pdf |work=? |access-date=29 September 2017 |archive-url=https://web.archive.org/web/20171010084126/http://www.amc.af.mil/Portals/12/documents/AFD-131018-052.pdf |archive-date=10 October 2017 |url-status=live}}</ref>