Editing Half-track (section)

==History==

===Kégresse track===
{{Main|Kégresse track}}
[[Image:Kegresse tsar17.jpg|left|thumb|A car from Tsar [[Nicholas II of Russia]]'s personal car pool converted with [[Kégresse track]]s]]
[[File:Rolls-Royce Silver Ghost Kégresse.jpg|thumb|[[Vladimir Lenin]]'s [[Rolls-Royce Silver Ghost]] with [[Kégresse track]], converted by the [[Kirov Plant|Putilov Plant]]), at [[Gorki Leninskiye]]]]

The French engineer [[Adolphe Kégresse]] converted a number of cars from the personal car pool of Tsar [[Nicholas II of Russia]] to half-tracks in 1911. The [[Kégresse track]] used a flexible belt rather than interlocking metal segments. It was applied to several vehicles in the imperial garage, including [[Rolls-Royce Limited|Rolls-Royce]] cars and [[Packard]] trucks. The [[Imperial Russian Army]] also fitted the system to a number of its [[Austin Armoured Car]]s. From 1916 onward, Austin-Putilov model  military half-tracks were produced   along the same lines at the [[Kirov Plant|Putilov Plant]] using trucks and French track parts.

After the [[Russian Revolution]] and the establishment of the [[Soviet Union]], Kégresse returned to his native France, where the system was used on [[Citroën]] cars between 1921 and 1937 for off-road and military vehicles.

===Steam log hauler===
[[Image:Lombard steam log hauler.jpg|thumb|right|A restored Lombard steam log hauler in New Hampshire, US, in 2008]]
[[Image:Holt75pk.jpg|thumb|right|alt=An early bulldozer-like tractor, on crawler tracks, with a leading single wheel for steering - projecting from the front - on an extension to the frame. The large internal combustion engine is in full view, with the cooling radiator prominent at the front. An overall roof is supported by thin rods, and side protection sheeting is rolled up under the edge of the roof.|The Holt 75 model gasoline-powered Caterpillar tractor. Later models were produced without the front "tiller wheel".]]

The concept originated with log hauling in the northeastern US, with the [[Lombard Steam Log Hauler]] built by [[Alvin Lombard]] of [[Waterville, Maine]], from 1899 to 1917. The vehicle resembled a railway steam locomotive, with sled steering (or wheels) in front and chain-driven rear tracked rear crawlers driven by chains instead of the driving wheels of a locomotive.<ref>{{Cite web
| url         = http://files.asme.org/ASMEORG/Communities/History/Landmarks/5587.pdf
| title       = Lombard Steam Log Hauler
| access-date  = 6 January 2009
| author      = Lore A Rogers and Caleb W Scribner
| publisher   = American Society of Mechanical Engineers
| archive-url  =https://web.archive.org/web/20061005204934/http://files.asme.org/ASMEORG/Communities/History/Landmarks/5587.pdf
| archive-date =2006-10-05
| url-status    = dead
}}</ref>

By 1907, [[circus|dog and pony show]] operator H. H. Linn abandoned his gas-and-steam-powered four- and six-wheel-drive creations and had Lombard build a motor home/traction engine run by an underslung four-cylinder Brennan gasoline engine to travel the unimproved roads of the day, with wheels at the front and tracks at the rear: the first payload-carrying half-track. By 1909 this was replaced by a smaller machine with two wheels at the front and a single track behind, since rural wooden bridges presented problems.

Stability issues, together with a dispute between Linn and Lombard, led Linn to create the Linn Manufacturing Company, builder of the [[Linn tractor]], for building and putting onto the market his own improved civilian half-track–style machines. Lombard attempted to follow but, for the most part, remained a pulling machine. Linn would later register "Haftrak" and "Catruk" as trademarks, the latter for a half-track meant to convert hydraulically from truck to crawler configuration.

[[File:Artillery tractor in France Vosges Spring 1915.jpg|thumb|left|Artillery tractors (here a [[Benjamin Holt|Holt]] tractor) used by the French Army in 1914-1915]]
[[Image:HoltTractorFrontviewAnd8inchHowitzer.jpg|thumb|right|alt=A Holt seventy-five tractor towing a field gun through a war-damaged village in Europe. The tractor is stacked high with supplies, and a number of uniformed soldiers are walking alongside.|A Holt tractor towing artillery through a French village in 1916]]

===World War I===
[[Tractor]]s used to tow [[artillery]] and designs with front wheels and tracks at the rear began to appear prior to the outbreak of war, often based on agricultural machines such as the [[Holt tractor]]. The basic half-track concept was originally showcased by the British during the war.

With such tractors, the tactical use of heavier guns to supplement the light horse-drawn [[field gun]]s became feasible. For example, in the British Army it allowed the heavy guns of the [[Royal Garrison Artillery]] to be used flexibly on the battlefield. In England, starting in 1905, [[David Roberts (engineer)|David Roberts]] of [[Richard Hornsby & Sons]] had attempted to interest British military officials in a tracked vehicle, but failed.

Holt bought the patents related to the "chain track" [[track-type tractor]] from Richard Hornsby & Sons in 1914<ref>{{cite web | url = http://hornsbycrawler.org/ | title = Hornsby Steam Crawler | first = George | last = Hoffman | date = 2007-02-21 | location = [[British Columbia]] }}</ref> for £4,000. Unlike the Holt tractor, which had a steerable tiller wheel in front of the tracks, the Hornsby crawler was steered by controlling power to each track.<ref name="about">{{cite web|url=http://inventors.about.com/od/bstartinventions/a/bulldozer.htm |archive-url=https://archive.today/20121208161805/http://inventors.about.com/od/bstartinventions/a/bulldozer.htm |url-status=dead |archive-date=December 8, 2012 |title=History of Bulldozers| first= Mary |last=Bellis|publisher= About.com |access-date=2010-02-28 }}</ref>

When World War I broke out, with the problem of [[trench warfare]] and the difficulty of transporting supplies to the front, the pulling power of [[Continuous track|crawling-type]] tractors drew the attention of the military. With tanks coming onto the scene, however, the combination of tracks and wheels seemed impractical when fully tracked or six-wheel, four-wheel drive vehicles were available.

The half-track saw a comeback in the 1930s, with development occurring in several countries that would use them in World War II. The White Motor Company, which had designed armored cars for the [[United States Army]] and [[United States Marines]], continued after the First World War to develop armored cars and added tracks for the [[M2 half-track car]] and [[M3 half-track]].

===''Autochenille'' and ''autoneige''===
There were many civilian half-track experiments in the 1920s and 1930s. The [[Citroën]] company sponsored several scientific expeditions crossing deserts in North Africa and Central Asia, using their ''autochenilles''. After World War I, the US military wanted to develop a semi-tracked personnel carrier vehicle, so it looked at these civilian half-tracks. In the late 1920s the US Army purchased several Citroën-Kégresse vehicles for evaluation followed by a licence to produce them. This resulted in the Army Ordnance Department building a prototype in 1939. In September 1940 it went into production with the military M2 and M3 half-track versions.

[[File:Bombardier (PSF).jpg|thumb|left|Bombardier]]

With the snow and ice of [[Canada]] in mind, [[Joseph-Armand Bombardier]] developed 7- and 12-passenger half-track ''autoneiges'' in the 1930s, starting what would become the [[Bombardier Inc.|Bombardier]] industrial conglomerate. The Bombardier vehicle had tracks for propulsion in the rear and skis for steering in front. The skis could be replaced with wheels in the summer, but this was uncommon.

[[File:BA-30 armored car.jpg|thumb|left|BA-30 armored car]]

The Red Army also experimented with half-tracks, such as the [[BA-30]], but found them expensive and unreliable. Although not a feature on American World War II vehicles, steering could be assisted by track braking, controlled by the steering wheel.


===World War II half-track production===
[[File:9th Armored Division, Engers, Germany 03-27-45.jpg|thumb|right|[[9th Armored Division (United States)|US 9th Armored Division]] halftracks advance through [[Engers]], Germany, March 27, 1945]]

In the US, 56,000 halftracks were produced by four primary manufacturers, the largest being the [[White Motor Company]], the original designer, with a total of 15,414 accepted by the War Department. Two other manufacturers, [[Autocar Company|Autocar]] and [[Diamond T]], built 12,168 and 12,421, respectively.

[[File:Multiple Gun Motor Carriage.jpg|thumb|left|M16 .50 AA Quad on an [[M3 half-track]]]]

The fourth manufacturer of American-made half-tracks was the International Motor Truck Corporation division of [[International Harvester]]. IH built approximately 12,853 half-tracks at its Springfield Works, which were shipped to Europe for use by British and French troops. In 1942, it produced 152 M5 units and 5 M14 units; in 1943, 2,026 M9 units, 1,407 M0A1 units, 4,473 M5 units, 1,600 M14 units, and 400 M17 units; in 1944, 1,100 M5A1 units and 1,100 M17 units also at the Springfield Works; and in 1945 589 M5A1 and 1 M5A3 units. 

The IHC half-tracks differed visibly from the White, Diamond T, and AutoCar units in several ways. The IHC units had flat front fenders instead of fenders with compound curves; used the International Red Diamond 450 engines instead of the Hercules 160AX; used IHC Model 1856 4-speed transmissions instead of the Spicer 4-speed transmissions; had IHC Model FOK-1370 front drive axles instead of the Timken; used IHC Model RHT-1590 axles in the rear instead of the Timken; and were constructed with fully welded armor with rounded rear corners instead of the bolted armor with square corners.<ref>Crismon, Fredrerick W., "International Trucks" 1995; pp 173-174, 179, 181, 185, 186-188, 192</ref>

{{clarification needed span|text=These designs|reason= Which designs?|date=March 2025}} were also produced under license in Canada, and were widely supplied under the [[Lend Lease]] program, with 5,000 supplied to the USSR alone.<ref>Dunn, Walter Scott, ''Stalin's keys to victory: the rebirth of the Red Army'', p.156</ref>

===World War II half-track use===
[[File:Crowds of French patriots line the Champs Elysees.jpg|thumb|Allied victory parade August 23, 1944, with IH Half-Tracks]]

In August 1944, Allied forces [[Liberation of Paris|liberated Paris]]. The first vehicle to enter the city was an M3 named "España Cañí" and driven by Spanish soldiers fighting under the French tricolor. There followed several days of parades in late August. One parade of 25 August 1944 was down the [[Champs-Élysées]], with [[Charles de Gaulle]] leading throngs of Parisians, and French soldiers driving IH half-tracks.

[[File:Bundesarchiv Bild 101I-801-0664-37, Berlin, Unter den Linden, Schützenpanzer.jpg|left|thumb|A German ''Schützenpanzer'' [[Sd.Kfz. 251]] half-track. Photograph taken in 1942 in Berlin]]

====Infantry transporters====
Half-tracks were used extensively as inventory transporters in World War II, especially by the Germans with their armored [[Demag]]-designed [[Sd.Kfz. 250]]s and [[Hanomag]]-designed [[Sd.Kfz. 251]]s; and by the Americans with their [[M2 Half Track Car|M2]]s and [[M3 Half-track|M3]]s.

====Support weapon platforms====
Half-tracks were widely used as [[mortar carrier]]s, self-propelled [[anti-aircraft|anti-aircraft gun]]s, self-propelled [[anti-tank|anti-tank gun]]s, [[armored fighting vehicle]]s and in other tasks.

[[File:Bundesarchiv Bild 101I-665-6823-11, Russland, Flak auf Halbkettenfahrzeug im Erdeinsatz.jpg|thumb|right|A German [[Sd.Kfz. 10#Sd.Kfz. 10.2F4 and 10.2F5|Sd.Kfz. 10/4 or 10/5]]
with ''Behelfspanzerung'']]

====Utility and tractor half-tracks====
[[File:NSU Kettenkrad 36PS 1944 1.JPG|thumb|right|A small [[Kettenkrad|Sd.Kfz. 2]], with the characteristic ''Schachtellaufwerk'' overlapped/interleaved roadwheels]]

The Germans used a small 2 seater 1/2-ton class half-track "motorcycle", the [[Sd.Kfz. 2]] (better known as the ''Kleines Kettenkraftrad'' HK 101 or ''Kettenkrad'' for short – ''Ketten'' meaning tracks, and ''krad'' being the military abbreviation of the German word ''Kraftrad'', the administrative German term for motorcycle), to pull small artillery guns, for ammunition haulage, general transport and as a ground towing vehicle for the [[Messerschmitt Me 262]] jet fighter. Built by [[NSU Motorenwerke AG]] [[Neckarsulm]] and [[:de:Stoewer|Stoewer Werke]] [[Stettin]], a total of 8,345 vehicles were produced between 1940 and 1944.

Other Wehrmacht models were:
* 1-ton class, [[Sd.Kfz. 10]] produced by Demag, Berlin; Adler, Frankfurt am Main; Büssing-NAG, Brunswick; Phänomen, Cottbus and Saurer, Vienna, a total of 25,000 vehicles - its drivetrain was used for the [[Sd.Kfz. 250]]
* 3-ton class, [[Sd.Kfz. 11]] produced by Hanomag, Adler, Auto-Union and Skoda from 1938 to 1944, a total of 25,000 vehicles - its drivetrain was used for the [[Sd.Kfz. 251]]
* 5-ton class. [[Sd.Kfz. 6]], manufactured by Büssing-NAG, Berlin-Oberschönweide; Daimler-Benz and Praga (Czechoslovakia), about 3,500 vehicles in total
* 8-ton class. [[Sd.Kfz. 7]], production was of about 12,000 vehicles
* 12-ton class. [[Sd.Kfz. 8]], some 4,000 vehicles were produced by five manufacturers
* 18-ton class. [[Sd.Kfz. 9]], a production of only 2,000 vehicles

Larger German half-track tractors were used to tow anti-tank and field artillery pieces. The largest of these were also used by mechanical engineers to retrieve bogged down vehicles or perform repairs such as engine maintenance. [[Maultier]] half-tracks used to transport supplies to forward units were essentially civilian trucks which had had their rear axles replaced by [[Panzer I]] or [[Panzer II]] running gear. A replacement half-track design introduced later in World War II, the 1943-introduced ''[[Schwerer Wehrmachtschlepper]]'', was meant to replace the 3-tonne and 5-tonne capacity models – only some 825 examples were built before the war's end.

A common feature of virtually all German World War II half-tracks was the so-called ''Schachtellaufwerk'' overlapped/interleaved roadwheel arrangement with a "slack track" system possessing no return rollers under the return run of track, used from the small ''Kettenkrad'' to the nine-tonne capacity [[Sd.Kfz. 9]] vehicle, and most famously used on Henschel's [[Tiger I]] and MAN's [[Panther tank|Panther]] main battle tanks.

===Cold War use===
Half-tracks were extensively used after World War II until the late 1960s, mostly in form of surplus World War II vehicles. Half-tracks saw combat in the [[French colonial empire]] in the [[First Indochina War]] and the [[Algerian War]]; in the [[Indo-Pakistani wars and conflicts]]; and the early wars of the [[Arab–Israeli conflict]].

Half-tracks continued in use by the [[Israeli Army]] where they were deemed to outperform fully tracked and fully wheeled vehicles for non-combat payload tasks such as carrying telecommunications equipment. As of March 2008, 600 half-tracks were still officially listed as on active duty.<ref>{{Cite web| url=http://www.inss.org.il/upload/(FILE)1206270841.pdf| title=Israel Armed Forces| access-date=2 June 2009| archive-url=https://web.archive.org/web/20080813024448/http://www.inss.org.il/upload/%28FILE%291206270841.pdf| archive-date=2008-08-13| url-status        =dead}}</ref>

<gallery mode=packed heights=180>
Image:M3-Halftrack-with-20mm-cannon.jpg|Israeli modified M3 Half-track, armed with 20&nbsp;mm cannon
image:SdKfz11-2.jpg|German [[Sd.Kfz. 11]] half-track
</gallery>