Difference between first cavalry division and first armored division?

Answer 1

During the Vietnam era; the 1st (Air) Cavalry Division was an "Airmobile Division", a new class of infantry invented and combat tested in Vietnam (in 1965 at the battle of Ia Drang to be exact), and was similar to WWII's invention of the "Airborne Division" during that war. Airmobile Divisions=Helicopter borne/Airborne Divsions=Paratroopers.

Thus Airmobile Divisions were originally helicopter borne infantrymen. However (during Vietnam at least, when things were abit more experimental) "Cavalry" also meant "RECONNAISSANCE", thusly the 1st Air Cav Division was not only an airmobile infantry outfit, they were also LOOKING (SEARCHING, which is a form of reconnaissance) for the enemy...then landing into the LZ for the assault.

The 101st Abn (Amb) (again in Vietnam) was also designated as an "Airmobile Division" but was primarily intended for assaulting the enemy, but in "real world use" also performed the functions of "Searching and destroying" the enemy.

Armored Divisions (again Vietnam era) consisted of Armor Brigades, which in turn consisted of Armor Battalions (Tank Battalions). During this time period, US Army armored division consisted of M60 Combat Tanks (aka MBTs). These were primarily stationed in Europe (Germany) and ROK (South Korea). The M48A3 Patton tanks of course were being expended in Vietnam.

US Army Armored Divisions also contained 1 Armored Cav Squadron. The Cav Sqd performed Screening, Security, and Reconnaissance for the Division Commander. For these missions, the Cav utilized the brand new (in 1969) M551 Sheridan light tank (an aluminum hulled officially desigated ARMORED AIRBORNE RECONNAISSANCE ASSAULT VEHICLE). In Europe based units, the Cav Sheridans were programmed to fire the Shillelagh missile from the M551's 152mm tube, but in Vietnam the Sheridan always fired the 152mm cannon, as Shillelaghs were not sent to Vietnam.

Both Cav & Armored divisions had choppers assigned to them.