The M1 series tank is equipped with a 1500 horsepower Lycoming Textron gas turbine engine coupled to an Allison hydrokenetic transmission with four forward and two reverse gears. It's tactical crusing range is approximately 275 miles. Despite it's weight, the M1 can attain a top speed of nearly 45 miles per hour. The main armament is a 120mm smooth bore cannon, which replaced the 105mm gun on the initial M1 version. It has day/night fire on the move capability which is provided by a laser range finder, thermal imaging night sight, optical day sight, and a digital ballistic computer. Both the fuel and ammunition are compartmented to enhance survivability. The hull and turret are protected by advanced armor similar to the Chobam armor developed by the British Ministry of Defense. When required, the Abrams may be fitted with "reactive armor" to thwart armor-defeating munitions.
Although fielded in 1980, the Abrams remained untested for over 10 years. When Iraq invaded Kuwait in August 1990, there were concerns that the Abrams would fall victim to the sand and long months of continuous operation without the luxury of peacetime maintenance facilities. There were also doubts about the combat survivability of the extensive turret electronics. Immediately following President Bush's decision to commit US forces to the Gulf region in defense of Kuwait and Saudi Arabia, American armored units began the difficult process of relocating to the threatened area. Due to the shear size and weight of the Abrams, the C-5 Galaxy, the largest cargo aircraft in the US Air Force inventory, was only able to handle one tank at a time. This meant that nearly all of the Abrams tanks deployed in the Gulf War were shipped by cargo ship. Although slow in coming, the arrival of the Abrams was much welcomed by Allied forces, as it is capable of defeating any tank in the Iraqi inventory.
The Iraqi Army had a considerable array of tanks, mostly purchased from the former Soviet Union. Chief among these were about 500 T-72's. These modern Soviet tanks were armed with an excellent 125mm smoothbore weapon and had many of the same advanced features found on the Abrams. Despite it's advanced design, the T-72 proved to be inferior to the M1A1's deployed during the Gulf War, and compared more closely with the older M60A3 tanks used there by the US Marine Corps. In addition, Iraq had a number of earlier Soviet models: perhaps as many as 1,600 T-62 and about 700 T-54, both of which were developed in the 1960's. These tanks were widely regarded as clearly inferior to the Abrams, but were expected to be highly reliable mechanically. The Gulf War provided military tacticians with an opportunity to evaluate developments in tank design that had not been available since World War II.
In his book "Desert Victory - The War for Kuwait", author Norman Friedman writes that "The U.S. Army in Saudi Arabia probably had about 1,900 M1A1 tanks. Its ability to fire reliably when moving at speed over rough ground (because of the stabilized gun mount) gave it a capability that proved valuable in the Gulf. The Abrams tank also has… vision devices that proved effective not only at night, but also in the dust and smoke of Kuwaiti daytime. On average, an Abrams outranged an Iraqi tank by about 1,000 meters." The actual numbers of Abrams M1 and M1A1 tanks deployed to the Gulf War (according to official DOD sources) are as follows: A total of 1,848 M1A1 and M1A1 "Heavy Armor" (or HA) tanks were deployed between the US Army and Marine Corp (who fielded 16 M1A1's and 60 M1A1(HA) tanks).
As the Gulf War shifted pace from Operation Desert Shield to Operation Desert Storm, and the preparatory bombardment lifted, U.S. Abrams tanks spearheaded the attack on Iraqi fortifications and engaged enemy tanks whenever and wherever possible. Just as they had done in the Iran-Iraq War, the Iraqi Army used it's tanks as fixed anti-tank and artillery pieces, digging them into the ground to reduce target signature. However, this also prevented their quick movement and Allied air power smashed nearly 50% of Iraq's tank threat before Allied armor had moved across the border. After that the Abrams tanks quickly destroyed a number of Iraqi tanks that did manage to go mobile.
The Abrams' thermal sights were unhampered by the clouds of thick black smoke over the battlefield that were the result of burning Kuwaiti oil wells. In fact many Gunners relied on their "night" sights in full daylight. Such was not the case with the sights in the Iraqi tanks, which were being hit from units they could not even see. Concerns about the M1A1's range were eliminated by a massive resupply operation that will be studied for years as a model of tactical efficiency.
During the Gulf War only 18 Abrams tanks were taken out of service due to battle damage: nine were permanent losses, and another nine suffered repairable damage, mostly from mines. Not a single Abrams crewman was lost in the conflict. There were few reports of mechanical failure. US armor commanders maintained an unprecedented 90% operational readiness for their Abrams Main Battle Tanks.
http://www.fas.org/man/dod-101/sys/land/m1.htm