M8 Greyhound
The M8 light armored car is a 6×6 armored car produced by the Ford Motor Company during World War II. It was used from 1943 by United States and British forces in Europe and the Pacific until the end of the war. The vehicle was widely exported and as of 2024 still remained in service with some countries.
In British service, the M8 was known as the "Greyhound", a service name seldom, if ever, used by the US. The British Army found it too lightly armored, particularly the hull floor, which anti-tank mines could easily penetrate. Nevertheless, it was produced in large numbers. The M8 Greyhound's excellent road mobility made it a great supportive element in the advancing American and British armored columns. It was marginal cross country, especially in mud.
Development and production history
In July 1941, the U.S. Army Ordnance Department initiated the development of a new fast tank destroyer to replace the M6 37 mm gun motor carriage, which was essentially a ¾-ton truck with a 37 mm gun installed in the rear bed. The requirement was for a 6×4 wheeled vehicle armed with a 37 mm gun, a coaxial machine gun mounted in a turret, and a machine gun in the front hull. Its glacis armor was supposed to withstand fire from a machine gun and side armor from a machine gun. Prototypes were submitted by Studebaker, Ford and Chrysler, all of them quite similar in design and appearance.In April 1942, the T22 was selected, despite complaints about deficiencies, due to the need for vehicles. By then, it was clear that the 37 mm gun would not be effective against the front armor of German tanks; so, the new armored car, now designated the M8, took on a reconnaissance role instead. Contract issues and minor design improvements delayed serial production until March 1943. Production ended in June 1945. A total of 8,523 M8 armored cars, and 3,791 of its lighter M20 variant, were built. The M8s and M20s were manufactured at Ford Motor Company plants in Chicago, Illinois, and Saint Paul, Minnesota; the St Paul plant built 6,397 M8s to Chicago's 2,126; the 3,791 M20s were produced at the Chicago plant only.
In May 1942, having viewed the prototype, the British Tank Mission turned down the offer to acquire the M8 through lend-lease. It was named "Greyhound" in keeping with other U.S. armored cars already ordered by the British, such as the T18 Boarhound, the T17 Deerhound, the T17E1 Staghound and the M38 Wolfhound.
| Month | M8 | M20 |
| March 1943 | 15 | |
| April 1943 | 31 | |
| May 1943 | 110 | |
| June 1943 | 169 | |
| July 1943 | 512 | 126 |
| August 1943 | 314 | 205 |
| September 1943 | 803 | 275 |
| October 1943 | 545 | 293 |
| November 1943 | 1,000 | 400 |
| December 1943 | 800 | 325 |
| January 1944 | 562 | 214 |
| February 1944 | 468 | 193 |
| March 1944 | 241 | 53 |
| April 1944 | 223 | 48 |
| May 1944 | 241 | 53 |
| June 1944 | 234 | 32 |
| July 1944 | 256 | 29 |
| August 1944 | 243 | 83 |
| September 1944 | 232 | 158 |
| October 1944 | 234 | 160 |
| November 1944 | 234 | 159 |
| December 1944 | 215 | 155 |
| January 1945 | 232 | 97 |
| February 1945 | 144 | 153 |
| March 1945 | 162 | 163 |
| April 1945 | 150 | 150 |
| May 1945 | 153 | 156 |
| June 1945 | 111 | |
| Total | 8,523 | 3,791 |
Mission and operational performance
The cavalry reconnaissance troops assigned to infantry divisions and squadrons assigned to armored divisions or independent, and used at the direction of a division or corps commander, served as advance "eyes and ears," and this required speed and agility.When on the march, the cavalry was to make contact with enemy forces at the earliest practical moment and maintain it thereafter. The reconnaissance troops identified hostile units and reported their strength, composition, disposition and movement. During withdrawals, the cavalry often served as a screening force for the main units.
The M8 was not designed for offensive combat, and its firepower was adequate only against similar lightly armored enemy vehicles and infantry. With only the unarmored hull pan to serve as floor armor, the M8 was particularly vulnerable to mines.
The vehicle's other drawback was limited mobility in muddy or broken terrain or heavily wooded areas. The use of wheels, rather than continuous tracks like a tank, gave it a higher ground pressure which hampered its off-road performance in such terrain. Armored cavalry units preferred using the ¼-ton reconnaissance car in these environments. A large turning radius, limited wheel travel, and open differentials also limited its cross-country mobility and made the M8 susceptible to immobilization off-road in off-camber terrain and defiles. This led operators to using the vehicle mostly on existing roads and paths, where it became vulnerable to ambush. Conversely, the performance of the M8 on hard surfaces was exceptional, with the vehicle having a long range and able to consistently maintain its top speed of 55 mph. In addition, as a wheeled vehicle, the M8 was generally more reliable than tracked vehicles of similar size, requiring far less maintenance and logistical support.
Description
The M8's armor was thin, but it provided protection for the crew from small-arms fire and shrapnel, enough so that the vehicle could carry out its main mission of reconnaissance. The frontal, sloped hull armor varied in thickness from The side and rear hull armor, also sloped but slightly less so than the front, was thick. The top armor was thick, as was the floor. The turret was comparatively better protected than the hull, being thick all around, with an partial roof. The cast, rounded gun shield was uniformly thick.The M8 was fitted with a 37 mm M6 gun and a coaxially mounted Browning machine gun in a one-piece, cast mantlet, mounted in an open-topped, welded turret. The M8 was initially fitted without any kind of anti-aircraft defense; as a stopgap solution a.50 caliber Browning M2HB machine gun on a ring mount was retrofitted to nearly all vehicles already in service. A purpose-designed pintle was mounted on all late-production vehicles, but it saw comparatively little action due to a troubled development process.
The crew of four comprised a commander, gunner, driver, and radio operator. The driver and radio operator were seated in the forward section of the hull, while the commander and gunner sat in the turret, with the commander seated on the right, and the gunner on the left,
The vehicle carried 80 37 mm rounds when fitted with a single radio. Vehicles with a second radio installed only carried 16 main gun rounds. Some units solved this problem by cutting up the removed main ammunition rack and stowing 18 rounds in each sponson, under the radios. This raised the number of main gun rounds able to be carried to 52. Another modification involved fabricating a 43-round bin to be placed behind the driver's seat, and a 20-round bin attached to the framing of the turret basket. This raised the ammunition capacity up to 79 rounds. Machine gun ammunition consisted of 1,500.30 caliber rounds and 400.50 caliber rounds. In addition, the vehicle carried a mix of six Mk 2 fragmentation grenades, 6 MK 3 offensive grenades, four smoke grenades, and four M1 carbines for the crew, and six M1 anti-tank mines.
The M8 was powered by a Hercules Model JXD in-line six-cylinder 320 cubic-inch gasoline engine giving it a top speed of on-road, and off-road. With a fuel tank, it could manage a road range of The Hercules JXD ran more quietly than other engines of comparable power, which helped the M8 maintain an element of surprise and reduce the chance of being heard by the enemy. Because of this, the M8 armored cars in Patton's Third Army were known as "Patton's ghosts", since they were difficult to detect.
Each M8 armored car was equipped with a long-range radio set to communicate with higher headquarters. A short-range radio set was used to communicate within the unit, or with headquarters. The M8 weighed fully loaded with equipment and crew, and was capable of cross country or on highways without refueling. On normal roads, it was capable of a sustained speed of.
Early production models were fitted with the SCR-193 transmitter and SCR-312 Receiver due to lack of SCR-508 radio sets.
Service history
World War II
The M8 light armored car entered combat service with the Allies in the 1943 invasion of Sicily. It was purpose designed to serve as the primary basic command and communication combat vehicle of the U.S. Cavalry Reconnaissance troops. It was subsequently used by the US Army in Italy, Northwest Europe and the Pacific. In the latter theater, it was used mostly on Okinawa and the Philippines, and was even employed in its original tank destroyer role, as most Japanese tanks had armor that was vulnerable to its 37 mm gun. Over 1,000 were supplied via Lend-Lease to US allies; the United Kingdom, Free France and Brazil.File:UStankParis-edit1.jpg|thumb|upright|American troops in an M8 passing the Arc de Triomphe after the liberation of Paris
In the European Theater, the M8 received "varied acceptance." Its on-road performance was generally good, and it was armed and armored well enough for reconnaissance missions. On the other hand, the turning radius was considered too wide, and the engine was considered underpowered, routinely experiencing problems such as overheating from being run at high output continuously and/or having its ventilation louvers obstructed by personal equipment stored on the rear of the vehicle. Large numbers were regularly under repair, gaining the vehicle a reputation of being unreliable. Off-road mobility, especially on soft ground like mud or snow, was poor; in the mountainous terrain of Italy and in the Northwest European winter, the M8 was more or less restricted to roads, which greatly reduced its value as a reconnaissance vehicle. It was also very vulnerable to landmines. In February 1944, an add-on armor kit was designed to provide an extra quarter-inch of belly armor to reduce landmine vulnerability. Some crews also placed sandbags on the floor to make up for the thin belly armor. Another problem was that commanders often used their reconnaissance squadrons for fire support missions, for which the thinly-armored M8 was ill-suited. When it encountered German armored reconnaissance units, the M8 could easily penetrate their armor with its 37 mm gun. Conversely, its own thin armor was vulnerable to the 20 mm autocannons that German scout cars were equipped with.
Due to mobility problems with the M8, namely with regards to its suspension, the US Army's Special Armored Vehicle Board recommended the development of a new six-wheeled armored car which matched the M8's dimensions and size but was equipped with an articulated, independently sprung suspension system. Two prototypes, the Studebaker-developed T27 Armored Car and the T28 designed by Chevrolet were trialed by the US and also reviewed by the British Armed Forces. Although the T28 was standardized as the M28 and marked for production by Ford, the new armored car program was shelved and then permanently cancelled due to the end of the war, as impetus and funding for new military development projects had plummeted. The fleet of M8 and M20 armored cars already available was then considered more than adequate for the postwar US Army, which was demobilizing thousands of personnel and already had large stockpiles of equipment surplus to its requirements.