Carpet Bombing was a technique used in war against the GLA in Generals and Generals: Zero Hour. In case of the former, carpet bombing was only seen sporadically in the single-player campaign. In case of the latter, however, it became a standard gameplay element available to Chinese generals as well as the United States air force.
In Generals: Zero Hour, carpet bombing is available once a general is promoted to level 4. The exception to this rule is General Ta Hun Kwai, who needs to reach level 5. The volley of standard dumb bombs is delivered by Iron Dragon Bomber (fashioned after H-6 Bomber), over an area chosen by the general. The attack is most effective against concentrated units or buildings, spreading heavy damage in straight line. The aircraft is heavily armored, but could be downed by heavy anti-aircraft fire.
General Tsing Shi Tao's carpet bombers drop small nuclear bombs that, in addition to causing massive destruction, irradiate the area for some time.
Due to a bug in Generals: Zero Hour, carpet bombing is available in all single-player missions, even those that must not have it. For instance, in Operation Defending The Fire, the player is tasked with capturing a listening outpost, with the alleged prize being the ability to requisition carpet bombers. This, however, does not happen: Carpet bombing may be acquired after reaching the rank of 4-Start General in this mission and accomplishing the objective triggers nothing.
Inspection of the campaign maps with modding tools and World Builder reveals that the game code attempts to modify a superpower that corresponds to General Ta Hun Kwai's carpet bomber. Hence the player sees no effect.
American B-52 carpet bombers first appeared in Generals. In Operation Scorched Earth, Chinese forces requisitioned a U.S. carpet bomber for the operation. This is the only time in Generals, where the player can call in carpet bombers. Later in Operation Stormbringer, U.S. deployed three B-52 carpet bombers to level a GLA base.
Starting with Generals: Zero Hour, Air Force General Granger can call in carpet bomber from his Strategy Center in much the same way that Chinese do. However, these strikes were carried out by a faster stealth bomber with a larger payload.
Carpet Bombers are one of the "star units" advertised in the intro video of vanilla Generals, along with Tomahawk Missiles and Scud Launchers. However, they played a rather minor role in-game.